diff options
Diffstat (limited to '')
| -rw-r--r-- | layout/base/nsLayoutUtils.cpp | 9947 |
1 files changed, 9947 insertions, 0 deletions
diff --git a/layout/base/nsLayoutUtils.cpp b/layout/base/nsLayoutUtils.cpp new file mode 100644 index 0000000000..6d3bbf876a --- /dev/null +++ b/layout/base/nsLayoutUtils.cpp @@ -0,0 +1,9947 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "nsLayoutUtils.h" + +#include <algorithm> +#include <limits> + +#include "ActiveLayerTracker.h" +#include "DisplayItemClip.h" +#include "gfx2DGlue.h" +#include "gfxContext.h" +#include "gfxDrawable.h" +#include "gfxEnv.h" +#include "gfxMatrix.h" +#include "gfxPlatform.h" +#include "gfxRect.h" +#include "gfxTypes.h" +#include "gfxUtils.h" +#include "ImageContainer.h" +#include "ImageOps.h" +#include "ImageRegion.h" +#include "imgIContainer.h" +#include "imgIRequest.h" +#include "LayoutLogging.h" +#include "MobileViewportManager.h" +#include "mozilla/AccessibleCaretEventHub.h" +#include "mozilla/ArrayUtils.h" +#include "mozilla/BasicEvents.h" +#include "mozilla/ClearOnShutdown.h" +#include "mozilla/DisplayPortUtils.h" +#include "mozilla/glean/GleanMetrics.h" +#include "mozilla/dom/AnonymousContent.h" +#include "mozilla/dom/BrowserChild.h" +#include "mozilla/dom/CanvasUtils.h" +#include "mozilla/dom/Document.h" +#include "mozilla/dom/DocumentInlines.h" +#include "mozilla/dom/DOMRect.h" +#include "mozilla/dom/DOMStringList.h" +#include "mozilla/dom/Element.h" +#include "mozilla/dom/HTMLBodyElement.h" +#include "mozilla/dom/HTMLCanvasElement.h" +#include "mozilla/dom/HTMLImageElement.h" +#include "mozilla/dom/HTMLMediaElementBinding.h" +#include "mozilla/dom/HTMLVideoElement.h" +#include "mozilla/dom/InspectorFontFace.h" +#include "mozilla/dom/ImageBitmap.h" +#include "mozilla/dom/KeyframeEffect.h" +#include "mozilla/dom/SVGViewportElement.h" +#include "mozilla/dom/UIEvent.h" +#include "mozilla/intl/BidiEmbeddingLevel.h" +#include "mozilla/EffectCompositor.h" +#include "mozilla/EffectSet.h" +#include "mozilla/EventDispatcher.h" +#include "mozilla/EventStateManager.h" +#include "mozilla/FloatingPoint.h" +#include "mozilla/gfx/2D.h" +#include "mozilla/gfx/gfxVars.h" +#include "mozilla/gfx/PathHelpers.h" +#include "mozilla/IntegerRange.h" +#include "mozilla/layers/APZCCallbackHelper.h" +#include "mozilla/layers/APZPublicUtils.h" // for apz::CalculatePendingDisplayPort +#include "mozilla/layers/CompositorBridgeChild.h" +#include "mozilla/layers/PAPZ.h" +#include "mozilla/layers/StackingContextHelper.h" +#include "mozilla/layers/WebRenderLayerManager.h" +#include "mozilla/Likely.h" +#include "mozilla/LookAndFeel.h" +#include "mozilla/Maybe.h" +#include "mozilla/MemoryReporting.h" +#include "mozilla/PerfStats.h" +#include "mozilla/Preferences.h" +#include "mozilla/PresShell.h" +#include "mozilla/ProfilerLabels.h" +#include "mozilla/ProfilerMarkers.h" +#include "mozilla/RestyleManager.h" +#include "mozilla/ScopeExit.h" +#include "mozilla/ScrollOrigin.h" +#include "mozilla/ServoStyleSet.h" +#include "mozilla/ServoStyleSetInlines.h" +#include "mozilla/StaticPrefs_apz.h" +#include "mozilla/StaticPrefs_dom.h" +#include "mozilla/StaticPrefs_font.h" +#include "mozilla/StaticPrefs_gfx.h" +#include "mozilla/StaticPrefs_image.h" +#include "mozilla/StaticPrefs_layers.h" +#include "mozilla/StaticPrefs_layout.h" +#include "mozilla/StaticPtr.h" +#include "mozilla/StyleAnimationValue.h" +#include "mozilla/SVGImageContext.h" +#include "mozilla/SVGIntegrationUtils.h" +#include "mozilla/SVGTextFrame.h" +#include "mozilla/SVGUtils.h" +#include "mozilla/Telemetry.h" +#include "mozilla/ToString.h" +#include "mozilla/Unused.h" +#include "mozilla/ViewportFrame.h" +#include "mozilla/ViewportUtils.h" +#include "mozilla/WheelHandlingHelper.h" // for WheelHandlingUtils +#include "nsAnimationManager.h" +#include "nsAtom.h" +#include "nsBidiPresUtils.h" +#include "nsBlockFrame.h" +#include "nsCanvasFrame.h" +#include "nsCaret.h" +#include "nsCharTraits.h" +#include "nsCOMPtr.h" +#include "nsComputedDOMStyle.h" +#include "nsCSSAnonBoxes.h" +#include "nsCSSColorUtils.h" +#include "nsCSSFrameConstructor.h" +#include "nsCSSProps.h" +#include "nsCSSPseudoElements.h" +#include "nsCSSRendering.h" +#include "nsTHashMap.h" +#include "nsDisplayList.h" +#include "nsFlexContainerFrame.h" +#include "nsFontInflationData.h" +#include "nsFontMetrics.h" +#include "nsFrameList.h" +#include "nsFrameSelection.h" +#include "nsGenericHTMLElement.h" +#include "nsGkAtoms.h" +#include "nsICanvasRenderingContextInternal.h" +#include "nsIContent.h" +#include "nsIContentInlines.h" +#include "nsIContentViewer.h" +#include "nsIDocShell.h" +#include "nsIFrameInlines.h" +#include "nsIImageLoadingContent.h" +#include "nsIInterfaceRequestorUtils.h" +#include "nsIScrollableFrame.h" +#include "nsIWidget.h" +#include "nsListControlFrame.h" +#include "nsPIDOMWindow.h" +#include "nsPlaceholderFrame.h" +#include "nsPresContext.h" +#include "nsPresContextInlines.h" +#include "nsRefreshDriver.h" +#include "nsRegion.h" +#include "nsStyleConsts.h" +#include "nsStyleStructInlines.h" +#include "nsStyleTransformMatrix.h" +#include "nsSubDocumentFrame.h" +#include "nsTableWrapperFrame.h" +#include "nsTArray.h" +#include "nsTextFragment.h" +#include "nsTextFrame.h" +#include "nsTransitionManager.h" +#include "nsView.h" +#include "nsViewManager.h" +#include "prenv.h" +#include "RegionBuilder.h" +#include "RetainedDisplayListBuilder.h" +#include "TextDrawTarget.h" +#include "UnitTransforms.h" +#include "ViewportFrame.h" + +#include "nsXULPopupManager.h" + +// Make sure getpid() works. +#ifdef XP_WIN +# include <process.h> +# define getpid _getpid +#else +# include <unistd.h> +#endif + +using namespace mozilla; +using namespace mozilla::dom; +using namespace mozilla::image; +using namespace mozilla::layers; +using namespace mozilla::layout; +using namespace mozilla::gfx; +using mozilla::dom::HTMLMediaElement_Binding::HAVE_METADATA; +using mozilla::dom::HTMLMediaElement_Binding::HAVE_NOTHING; + +#ifdef DEBUG +// TODO: remove, see bug 598468. +bool nsLayoutUtils::gPreventAssertInCompareTreePosition = false; +#endif // DEBUG + +typedef ScrollableLayerGuid::ViewID ViewID; +typedef nsStyleTransformMatrix::TransformReferenceBox TransformReferenceBox; + +static ViewID sScrollIdCounter = ScrollableLayerGuid::START_SCROLL_ID; + +typedef nsTHashMap<nsUint64HashKey, nsIContent*> ContentMap; +static StaticAutoPtr<ContentMap> sContentMap; + +static ContentMap& GetContentMap() { + if (!sContentMap) { + sContentMap = new ContentMap(); + } + return *sContentMap; +} + +template <typename TestType> +static bool HasMatchingAnimations(EffectSet& aEffects, TestType&& aTest) { + for (KeyframeEffect* effect : aEffects) { + if (!effect->GetAnimation() || !effect->GetAnimation()->IsRelevant()) { + continue; + } + + if (aTest(*effect, aEffects)) { + return true; + } + } + + return false; +} + +template <typename TestType> +static bool HasMatchingAnimations(const nsIFrame* aFrame, + const nsCSSPropertyIDSet& aPropertySet, + TestType&& aTest) { + MOZ_ASSERT(aFrame); + + if (aPropertySet.IsSubsetOf(nsCSSPropertyIDSet::OpacityProperties()) && + !aFrame->MayHaveOpacityAnimation()) { + return false; + } + + if (aPropertySet.IsSubsetOf(nsCSSPropertyIDSet::TransformLikeProperties()) && + !aFrame->MayHaveTransformAnimation()) { + return false; + } + + EffectSet* effectSet = EffectSet::GetEffectSetForFrame(aFrame, aPropertySet); + if (!effectSet) { + return false; + } + + return HasMatchingAnimations(*effectSet, aTest); +} + +/* static */ +bool nsLayoutUtils::HasAnimationOfPropertySet( + const nsIFrame* aFrame, const nsCSSPropertyIDSet& aPropertySet) { + return HasMatchingAnimations( + aFrame, aPropertySet, + [&aPropertySet](KeyframeEffect& aEffect, const EffectSet&) { + return aEffect.HasAnimationOfPropertySet(aPropertySet); + }); +} + +/* static */ +bool nsLayoutUtils::HasAnimationOfPropertySet( + const nsIFrame* aFrame, const nsCSSPropertyIDSet& aPropertySet, + EffectSet* aEffectSet) { + MOZ_ASSERT( + !aEffectSet || + EffectSet::GetEffectSetForFrame(aFrame, aPropertySet) == aEffectSet, + "The EffectSet, if supplied, should match what we would otherwise fetch"); + + if (!aEffectSet) { + return nsLayoutUtils::HasAnimationOfPropertySet(aFrame, aPropertySet); + } + + if (aPropertySet.IsSubsetOf(nsCSSPropertyIDSet::TransformLikeProperties()) && + !aEffectSet->MayHaveTransformAnimation()) { + return false; + } + + if (aPropertySet.IsSubsetOf(nsCSSPropertyIDSet::OpacityProperties()) && + !aEffectSet->MayHaveOpacityAnimation()) { + return false; + } + + return HasMatchingAnimations( + *aEffectSet, + [&aPropertySet](KeyframeEffect& aEffect, const EffectSet& aEffectSet) { + return aEffect.HasAnimationOfPropertySet(aPropertySet); + }); +} + +/* static */ +bool nsLayoutUtils::HasAnimationOfTransformAndMotionPath( + const nsIFrame* aFrame) { + return nsLayoutUtils::HasAnimationOfPropertySet( + aFrame, + nsCSSPropertyIDSet{eCSSProperty_transform, eCSSProperty_translate, + eCSSProperty_rotate, eCSSProperty_scale, + eCSSProperty_offset_path}) || + (!aFrame->StyleDisplay()->mOffsetPath.IsNone() && + nsLayoutUtils::HasAnimationOfPropertySet( + aFrame, nsCSSPropertyIDSet::MotionPathProperties())); +} + +/* static */ +bool nsLayoutUtils::HasEffectiveAnimation( + const nsIFrame* aFrame, const nsCSSPropertyIDSet& aPropertySet) { + return HasMatchingAnimations( + aFrame, aPropertySet, + [&aPropertySet](KeyframeEffect& aEffect, const EffectSet& aEffectSet) { + return aEffect.HasEffectiveAnimationOfPropertySet(aPropertySet, + aEffectSet); + }); +} + +/* static */ +nsCSSPropertyIDSet nsLayoutUtils::GetAnimationPropertiesForCompositor( + const nsIFrame* aStyleFrame) { + nsCSSPropertyIDSet properties; + + // We fetch the effects for the style frame here since this method is called + // by RestyleManager::AddLayerChangesForAnimation which takes care to apply + // the relevant hints to the primary frame as needed. + EffectSet* effects = EffectSet::GetEffectSetForStyleFrame(aStyleFrame); + if (!effects) { + return properties; + } + + AnimationPerformanceWarning::Type warning; + if (!EffectCompositor::AllowCompositorAnimationsOnFrame(aStyleFrame, + warning)) { + return properties; + } + + for (const KeyframeEffect* effect : *effects) { + properties |= effect->GetPropertiesForCompositor(*effects, aStyleFrame); + } + + // If properties only have motion-path properties, we have to make sure they + // have effects. i.e. offset-path is not none or we have offset-path + // animations. + if (properties.IsSubsetOf(nsCSSPropertyIDSet::MotionPathProperties()) && + !properties.HasProperty(eCSSProperty_offset_path) && + aStyleFrame->StyleDisplay()->mOffsetPath.IsNone()) { + properties.Empty(); + } + + return properties; +} + +static float GetSuitableScale(float aMaxScale, float aMinScale, + nscoord aVisibleDimension, + nscoord aDisplayDimension) { + float displayVisibleRatio = + float(aDisplayDimension) / float(aVisibleDimension); + // We want to rasterize based on the largest scale used during the + // transform animation, unless that would make us rasterize something + // larger than the screen. But we never want to go smaller than the + // minimum scale over the animation. + if (FuzzyEqualsMultiplicative(displayVisibleRatio, aMaxScale, .01f)) { + // Using aMaxScale may make us rasterize something a fraction larger than + // the screen. However, if aMaxScale happens to be the final scale of a + // transform animation it is better to use aMaxScale so that for the + // fraction of a second before we delayerize the composited texture it has + // a better chance of being pixel aligned and composited without resampling + // (avoiding visually clunky delayerization). + return aMaxScale; + } + return std::max(std::min(aMaxScale, displayVisibleRatio), aMinScale); +} + +// The first value in this pair is the min scale, and the second one is the max +// scale. +using MinAndMaxScale = std::pair<MatrixScales, MatrixScales>; + +static inline void UpdateMinMaxScale(const nsIFrame* aFrame, + const AnimationValue& aValue, + MinAndMaxScale& aMinAndMaxScale) { + MatrixScales size = aValue.GetScaleValue(aFrame); + MatrixScales& minScale = aMinAndMaxScale.first; + MatrixScales& maxScale = aMinAndMaxScale.second; + + minScale = Min(minScale, size); + maxScale = Max(maxScale, size); +} + +// The final transform matrix is calculated by merging the final results of each +// transform-like properties, so do the scale factors. In other words, the +// potential min/max scales could be gotten by multiplying the max/min scales of +// each properties. +// +// For example, there is an animation: +// from { "transform: scale(1, 1)", "scale: 3, 3" }; +// to { "transform: scale(2, 2)", "scale: 1, 1" }; +// +// the min scale is (1, 1) * (1, 1) = (1, 1), and +// The max scale is (2, 2) * (3, 3) = (6, 6). +// This means we multiply the min/max scale factor of transform property and the +// min/max scale factor of scale property to get the final max/min scale factor. +static Array<MinAndMaxScale, 2> GetMinAndMaxScaleForAnimationProperty( + const nsIFrame* aFrame, + const nsTArray<RefPtr<dom::Animation>>& aAnimations) { + // We use a fixed array to store the min/max scales for each property. + // The first element in the array is for eCSSProperty_transform, and the + // second one is for eCSSProperty_scale. + const MinAndMaxScale defaultValue = + std::make_pair(MatrixScales(std::numeric_limits<float>::max(), + std::numeric_limits<float>::max()), + MatrixScales(std::numeric_limits<float>::min(), + std::numeric_limits<float>::min())); + Array<MinAndMaxScale, 2> minAndMaxScales(defaultValue, defaultValue); + + for (dom::Animation* anim : aAnimations) { + // This method is only expected to be passed animations that are running on + // the compositor and we only pass playing animations to the compositor, + // which are, by definition, "relevant" animations (animations that are + // not yet finished or which are filling forwards). + MOZ_ASSERT(anim->IsRelevant()); + + const dom::KeyframeEffect* effect = + anim->GetEffect() ? anim->GetEffect()->AsKeyframeEffect() : nullptr; + MOZ_ASSERT(effect, "A playing animation should have a keyframe effect"); + for (const AnimationProperty& prop : effect->Properties()) { + if (prop.mProperty != eCSSProperty_transform && + prop.mProperty != eCSSProperty_scale) { + continue; + } + + // 0: eCSSProperty_transform. + // 1: eCSSProperty_scale. + MinAndMaxScale& scales = + minAndMaxScales[prop.mProperty == eCSSProperty_transform ? 0 : 1]; + + // We need to factor in the scale of the base style if the base style + // will be used on the compositor. + const AnimationValue& baseStyle = effect->BaseStyle(prop.mProperty); + if (!baseStyle.IsNull()) { + UpdateMinMaxScale(aFrame, baseStyle, scales); + } + + for (const AnimationPropertySegment& segment : prop.mSegments) { + // In case of add or accumulate composite, StyleAnimationValue does + // not have a valid value. + if (segment.HasReplaceableFromValue()) { + UpdateMinMaxScale(aFrame, segment.mFromValue, scales); + } + + if (segment.HasReplaceableToValue()) { + UpdateMinMaxScale(aFrame, segment.mToValue, scales); + } + } + } + } + + return minAndMaxScales; +} + +MatrixScales nsLayoutUtils::ComputeSuitableScaleForAnimation( + const nsIFrame* aFrame, const nsSize& aVisibleSize, + const nsSize& aDisplaySize) { + const nsTArray<RefPtr<dom::Animation>> compositorAnimations = + EffectCompositor::GetAnimationsForCompositor( + aFrame, + nsCSSPropertyIDSet{eCSSProperty_transform, eCSSProperty_scale}); + + if (compositorAnimations.IsEmpty()) { + return MatrixScales(); + } + + const Array<MinAndMaxScale, 2> minAndMaxScales = + GetMinAndMaxScaleForAnimationProperty(aFrame, compositorAnimations); + + // This might cause an issue if users use std::numeric_limits<float>::min() + // (or max()) as the scale value. However, in this case, we may render an + // extreme small (or large) element, so this may not be a problem. If so, + // please fix this. + MatrixScales maxScale(std::numeric_limits<float>::min(), + std::numeric_limits<float>::min()); + MatrixScales minScale(std::numeric_limits<float>::max(), + std::numeric_limits<float>::max()); + + auto isUnset = [](const MatrixScales& aMax, const MatrixScales& aMin) { + return aMax.xScale == std::numeric_limits<float>::min() && + aMax.yScale == std::numeric_limits<float>::min() && + aMin.xScale == std::numeric_limits<float>::max() && + aMin.yScale == std::numeric_limits<float>::max(); + }; + + // Iterate the slots to get the final scale value. + for (const auto& pair : minAndMaxScales) { + const MatrixScales& currMinScale = pair.first; + const MatrixScales& currMaxScale = pair.second; + + if (isUnset(currMaxScale, currMinScale)) { + // We don't have this animation property, so skip. + continue; + } + + if (isUnset(maxScale, minScale)) { + // Initialize maxScale and minScale. + maxScale = currMaxScale; + minScale = currMinScale; + } else { + // The scale factors of each transform-like property should be multiplied + // by others because we merge their sampled values as a final matrix by + // matrix multiplication, so here we multiply the scale factors by the + // previous one to get the possible max and min scale factors. + maxScale = maxScale * currMaxScale; + minScale = minScale * currMinScale; + } + } + + if (isUnset(maxScale, minScale)) { + // We didn't encounter any transform-like property. + return MatrixScales(); + } + + return MatrixScales( + GetSuitableScale(maxScale.xScale, minScale.xScale, aVisibleSize.width, + aDisplaySize.width), + GetSuitableScale(maxScale.yScale, minScale.yScale, aVisibleSize.height, + aDisplaySize.height)); +} + +bool nsLayoutUtils::AreAsyncAnimationsEnabled() { + return StaticPrefs::layers_offmainthreadcomposition_async_animations() && + gfxPlatform::OffMainThreadCompositingEnabled(); +} + +bool nsLayoutUtils::AreRetainedDisplayListsEnabled() { +#ifdef MOZ_WIDGET_ANDROID + return StaticPrefs::layout_display_list_retain(); +#else + if (XRE_IsContentProcess()) { + return StaticPrefs::layout_display_list_retain(); + } + + if (XRE_IsE10sParentProcess()) { + return StaticPrefs::layout_display_list_retain_chrome(); + } + + // Retained display lists require e10s. + return false; +#endif +} + +bool nsLayoutUtils::DisplayRootHasRetainedDisplayListBuilder(nsIFrame* aFrame) { + return GetRetainedDisplayListBuilder(aFrame) != nullptr; +} + +RetainedDisplayListBuilder* nsLayoutUtils::GetRetainedDisplayListBuilder( + nsIFrame* aFrame) { + MOZ_ASSERT(aFrame); + MOZ_ASSERT(aFrame->PresShell()); + + // Use the pres shell root frame to get the display root frame. This skips + // the early exit in |nsLayoutUtils::GetDisplayRootFrame()| for popup frames. + const nsIFrame* rootFrame = aFrame->PresShell()->GetRootFrame(); + if (!rootFrame) { + return nullptr; + } + + const nsIFrame* displayRootFrame = GetDisplayRootFrame(rootFrame); + MOZ_ASSERT(displayRootFrame); + + return displayRootFrame->GetProperty(RetainedDisplayListBuilder::Cached()); +} + +bool nsLayoutUtils::GPUImageScalingEnabled() { + static bool sGPUImageScalingEnabled; + static bool sGPUImageScalingPrefInitialised = false; + + if (!sGPUImageScalingPrefInitialised) { + sGPUImageScalingPrefInitialised = true; + sGPUImageScalingEnabled = + Preferences::GetBool("layout.gpu-image-scaling.enabled", false); + } + + return sGPUImageScalingEnabled; +} + +void nsLayoutUtils::UnionChildOverflow(nsIFrame* aFrame, + OverflowAreas& aOverflowAreas, + FrameChildListIDs aSkipChildLists) { + // Iterate over all children except pop-ups. + FrameChildListIDs skip(aSkipChildLists); + skip += FrameChildListID::Popup; + + for (const auto& [list, listID] : aFrame->ChildLists()) { + if (skip.contains(listID)) { + continue; + } + for (nsIFrame* child : list) { + aOverflowAreas.UnionWith( + child->GetActualAndNormalOverflowAreasRelativeToParent()); + } + } +} + +static void DestroyViewID(void* aObject, nsAtom* aPropertyName, + void* aPropertyValue, void* aData) { + ViewID* id = static_cast<ViewID*>(aPropertyValue); + GetContentMap().Remove(*id); + delete id; +} + +/** + * A namespace class for static layout utilities. + */ + +bool nsLayoutUtils::FindIDFor(const nsIContent* aContent, ViewID* aOutViewId) { + void* scrollIdProperty = aContent->GetProperty(nsGkAtoms::RemoteId); + if (scrollIdProperty) { + *aOutViewId = *static_cast<ViewID*>(scrollIdProperty); + return true; + } + return false; +} + +ViewID nsLayoutUtils::FindOrCreateIDFor(nsIContent* aContent) { + ViewID scrollId; + + if (!FindIDFor(aContent, &scrollId)) { + scrollId = sScrollIdCounter++; + aContent->SetProperty(nsGkAtoms::RemoteId, new ViewID(scrollId), + DestroyViewID); + GetContentMap().InsertOrUpdate(scrollId, aContent); + } + + return scrollId; +} + +nsIContent* nsLayoutUtils::FindContentFor(ViewID aId) { + MOZ_ASSERT(aId != ScrollableLayerGuid::NULL_SCROLL_ID, + "Cannot find a content element in map for null IDs."); + nsIContent* content; + bool exists = GetContentMap().Get(aId, &content); + + if (exists) { + return content; + } else { + return nullptr; + } +} + +nsIFrame* nsLayoutUtils::GetScrollFrameFromContent(nsIContent* aContent) { + nsIFrame* frame = aContent->GetPrimaryFrame(); + if (aContent->OwnerDoc()->GetRootElement() == aContent) { + PresShell* presShell = frame ? frame->PresShell() : nullptr; + if (!presShell) { + presShell = aContent->OwnerDoc()->GetPresShell(); + } + // We want the scroll frame, the root scroll frame differs from all + // others in that the primary frame is not the scroll frame. + nsIFrame* rootScrollFrame = + presShell ? presShell->GetRootScrollFrame() : nullptr; + if (rootScrollFrame) { + frame = rootScrollFrame; + } + } + return frame; +} + +nsIScrollableFrame* nsLayoutUtils::FindScrollableFrameFor( + nsIContent* aContent) { + nsIFrame* scrollFrame = GetScrollFrameFromContent(aContent); + return scrollFrame ? scrollFrame->GetScrollTargetFrame() : nullptr; +} + +nsIScrollableFrame* nsLayoutUtils::FindScrollableFrameFor(ViewID aId) { + nsIContent* content = FindContentFor(aId); + if (!content) { + return nullptr; + } + + return FindScrollableFrameFor(content); +} + +ViewID nsLayoutUtils::FindIDForScrollableFrame( + nsIScrollableFrame* aScrollable) { + if (!aScrollable) { + return ScrollableLayerGuid::NULL_SCROLL_ID; + } + + nsIFrame* scrollFrame = do_QueryFrame(aScrollable); + nsIContent* scrollContent = scrollFrame->GetContent(); + + ScrollableLayerGuid::ViewID scrollId; + if (scrollContent && nsLayoutUtils::FindIDFor(scrollContent, &scrollId)) { + return scrollId; + } + + return ScrollableLayerGuid::NULL_SCROLL_ID; +} + +bool nsLayoutUtils::UsesAsyncScrolling(nsIFrame* aFrame) { +#ifdef MOZ_WIDGET_ANDROID + // We always have async scrolling for android + return true; +#endif + + return AsyncPanZoomEnabled(aFrame); +} + +bool nsLayoutUtils::AsyncPanZoomEnabled(const nsIFrame* aFrame) { + // We use this as a shortcut, since if the compositor will never use APZ, + // no widget will either. + if (!gfxPlatform::AsyncPanZoomEnabled()) { + return false; + } + + const nsIFrame* frame = nsLayoutUtils::GetDisplayRootFrame(aFrame); + nsIWidget* widget = frame->GetNearestWidget(); + if (!widget) { + return false; + } + return widget->AsyncPanZoomEnabled(); +} + +bool nsLayoutUtils::AllowZoomingForDocument( + const mozilla::dom::Document* aDocument) { + if (aDocument->GetPresShell() && + !aDocument->GetPresShell()->AsyncPanZoomEnabled()) { + return false; + } + // True if we allow zooming for all documents on this platform, or if we are + // in RDM and handling meta viewports, which force zoom under some + // circumstances. + BrowsingContext* bc = aDocument ? aDocument->GetBrowsingContext() : nullptr; + return StaticPrefs::apz_allow_zooming() || + (bc && bc->InRDMPane() && + nsLayoutUtils::ShouldHandleMetaViewport(aDocument)); +} + +static bool HasVisibleAnonymousContents(Document* aDoc) { + for (RefPtr<AnonymousContent>& ac : aDoc->GetAnonymousContents()) { + // We check to see if the anonymous content node has a frame. If it doesn't, + // that means that's not visible to the user because e.g. it's display:none. + // For now we assume that if it has a frame, it is visible. We might be able + // to refine this further by adding complexity if it turns out this + // condition results in a lot of false positives. + if (ac->ContentNode().GetPrimaryFrame()) { + return true; + } + } + return false; +} + +bool nsLayoutUtils::ShouldDisableApzForElement(nsIContent* aContent) { + if (!aContent) { + return false; + } + + if (aContent->GetProperty(nsGkAtoms::apzDisabled)) { + return true; + } + + Document* doc = aContent->GetComposedDoc(); + if (PresShell* rootPresShell = + APZCCallbackHelper::GetRootContentDocumentPresShellForContent( + aContent)) { + if (Document* rootDoc = rootPresShell->GetDocument()) { + nsIContent* rootContent = + rootPresShell->GetRootScrollFrame() + ? rootPresShell->GetRootScrollFrame()->GetContent() + : rootDoc->GetDocumentElement(); + // For the AccessibleCaret and other anonymous contents: disable APZ on + // any scrollable subframes that are not the root scrollframe of a + // document, if the document has any visible anonymous contents. + // + // If we find this is triggering in too many scenarios then we might + // want to tighten this check further. The main use cases for which we + // want to disable APZ as of this writing are listed in bug 1316318. + if (aContent != rootContent && HasVisibleAnonymousContents(rootDoc)) { + return true; + } + } + } + + if (!doc) { + return false; + } + + if (PresShell* presShell = doc->GetPresShell()) { + if (RefPtr<AccessibleCaretEventHub> eventHub = + presShell->GetAccessibleCaretEventHub()) { + // Disable APZ for all elements if AccessibleCaret tells us to do so. + if (eventHub->ShouldDisableApz()) { + return true; + } + } + } + + return StaticPrefs::apz_disable_for_scroll_linked_effects() && + doc->HasScrollLinkedEffect(); +} + +void nsLayoutUtils::NotifyPaintSkipTransaction(ViewID aScrollId) { + if (nsIScrollableFrame* scrollFrame = + nsLayoutUtils::FindScrollableFrameFor(aScrollId)) { +#ifdef DEBUG + nsIFrame* f = do_QueryFrame(scrollFrame); + MOZ_ASSERT(f && f->PresShell() && !f->PresShell()->IsResolutionUpdated()); +#endif + scrollFrame->NotifyApzTransaction(); + } +} + +nsContainerFrame* nsLayoutUtils::LastContinuationWithChild( + nsContainerFrame* aFrame) { + MOZ_ASSERT(aFrame, "NULL frame pointer"); + for (auto f = aFrame->LastContinuation(); f; f = f->GetPrevContinuation()) { + for (const auto& childList : f->ChildLists()) { + if (MOZ_LIKELY(!childList.mList.IsEmpty())) { + return static_cast<nsContainerFrame*>(f); + } + } + } + return aFrame; +} + +// static +FrameChildListID nsLayoutUtils::GetChildListNameFor(nsIFrame* aChildFrame) { + FrameChildListID id = FrameChildListID::Principal; + + MOZ_DIAGNOSTIC_ASSERT(!aChildFrame->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW)); + + if (aChildFrame->HasAnyStateBits(NS_FRAME_IS_OVERFLOW_CONTAINER)) { + nsIFrame* pif = aChildFrame->GetPrevInFlow(); + if (pif->GetParent() == aChildFrame->GetParent()) { + id = FrameChildListID::ExcessOverflowContainers; + } else { + id = FrameChildListID::OverflowContainers; + } + } else { + LayoutFrameType childType = aChildFrame->Type(); + if (LayoutFrameType::TableColGroup == childType) { + id = FrameChildListID::ColGroup; + } else if (aChildFrame->IsTableCaption()) { + id = FrameChildListID::Caption; + } else { + id = FrameChildListID::Principal; + } + } + +#ifdef DEBUG + // Verify that the frame is actually in that child list or in the + // corresponding overflow list. + nsContainerFrame* parent = aChildFrame->GetParent(); + bool found = parent->GetChildList(id).ContainsFrame(aChildFrame); + if (!found) { + found = parent->GetChildList(FrameChildListID::Overflow) + .ContainsFrame(aChildFrame); + MOZ_ASSERT(found, "not in child list"); + } +#endif + + return id; +} + +static Element* GetPseudo(const nsIContent* aContent, nsAtom* aPseudoProperty) { + MOZ_ASSERT(aPseudoProperty == nsGkAtoms::beforePseudoProperty || + aPseudoProperty == nsGkAtoms::afterPseudoProperty || + aPseudoProperty == nsGkAtoms::markerPseudoProperty); + if (!aContent->MayHaveAnonymousChildren()) { + return nullptr; + } + return static_cast<Element*>(aContent->GetProperty(aPseudoProperty)); +} + +/*static*/ +Element* nsLayoutUtils::GetBeforePseudo(const nsIContent* aContent) { + return GetPseudo(aContent, nsGkAtoms::beforePseudoProperty); +} + +/*static*/ +nsIFrame* nsLayoutUtils::GetBeforeFrame(const nsIContent* aContent) { + Element* pseudo = GetBeforePseudo(aContent); + return pseudo ? pseudo->GetPrimaryFrame() : nullptr; +} + +/*static*/ +Element* nsLayoutUtils::GetAfterPseudo(const nsIContent* aContent) { + return GetPseudo(aContent, nsGkAtoms::afterPseudoProperty); +} + +/*static*/ +nsIFrame* nsLayoutUtils::GetAfterFrame(const nsIContent* aContent) { + Element* pseudo = GetAfterPseudo(aContent); + return pseudo ? pseudo->GetPrimaryFrame() : nullptr; +} + +/*static*/ +Element* nsLayoutUtils::GetMarkerPseudo(const nsIContent* aContent) { + return GetPseudo(aContent, nsGkAtoms::markerPseudoProperty); +} + +/*static*/ +nsIFrame* nsLayoutUtils::GetMarkerFrame(const nsIContent* aContent) { + Element* pseudo = GetMarkerPseudo(aContent); + return pseudo ? pseudo->GetPrimaryFrame() : nullptr; +} + +#ifdef ACCESSIBILITY +void nsLayoutUtils::GetMarkerSpokenText(const nsIContent* aContent, + nsAString& aText) { + MOZ_ASSERT(aContent && aContent->IsGeneratedContentContainerForMarker()); + + aText.Truncate(); + + nsIFrame* frame = aContent->GetPrimaryFrame(); + if (!frame) { + return; + } + + if (frame->StyleContent()->ContentCount() > 0) { + for (nsIFrame* child : frame->PrincipalChildList()) { + nsIFrame::RenderedText text = child->GetRenderedText(); + aText += text.mString; + } + return; + } + + if (!frame->StyleList()->mListStyleImage.IsNone()) { + // ::marker is an image, so use default bullet character. + static const char16_t kDiscMarkerString[] = {0x2022, ' ', 0}; + aText.AssignLiteral(kDiscMarkerString); + return; + } + + frame->PresContext() + ->FrameConstructor() + ->GetContainStyleScopeManager() + .GetSpokenCounterText(frame, aText); +} +#endif + +// static +nsIFrame* nsLayoutUtils::GetClosestFrameOfType(nsIFrame* aFrame, + LayoutFrameType aFrameType, + nsIFrame* aStopAt) { + for (nsIFrame* frame = aFrame; frame; frame = frame->GetParent()) { + if (frame->Type() == aFrameType) { + return frame; + } + if (frame == aStopAt) { + break; + } + } + return nullptr; +} + +/* static */ +nsIFrame* nsLayoutUtils::GetPageFrame(nsIFrame* aFrame) { + return GetClosestFrameOfType(aFrame, LayoutFrameType::Page); +} + +/* static */ +nsIFrame* nsLayoutUtils::GetStyleFrame(nsIFrame* aPrimaryFrame) { + MOZ_ASSERT(aPrimaryFrame); + if (aPrimaryFrame->IsTableWrapperFrame()) { + nsIFrame* inner = aPrimaryFrame->PrincipalChildList().FirstChild(); + // inner may be null, if aPrimaryFrame is mid-destruction + return inner; + } + + return aPrimaryFrame; +} + +const nsIFrame* nsLayoutUtils::GetStyleFrame(const nsIFrame* aPrimaryFrame) { + return nsLayoutUtils::GetStyleFrame(const_cast<nsIFrame*>(aPrimaryFrame)); +} + +nsIFrame* nsLayoutUtils::GetStyleFrame(const nsIContent* aContent) { + nsIFrame* frame = aContent->GetPrimaryFrame(); + if (!frame) { + return nullptr; + } + + return nsLayoutUtils::GetStyleFrame(frame); +} + +CSSIntCoord nsLayoutUtils::UnthemedScrollbarSize(StyleScrollbarWidth aWidth) { + switch (aWidth) { + case StyleScrollbarWidth::Auto: + return 12; + case StyleScrollbarWidth::Thin: + return 6; + case StyleScrollbarWidth::None: + return 0; + } + return 0; +} + +/* static */ +nsIFrame* nsLayoutUtils::GetPrimaryFrameFromStyleFrame(nsIFrame* aStyleFrame) { + nsIFrame* parent = aStyleFrame->GetParent(); + return parent && parent->IsTableWrapperFrame() ? parent : aStyleFrame; +} + +/* static */ +const nsIFrame* nsLayoutUtils::GetPrimaryFrameFromStyleFrame( + const nsIFrame* aStyleFrame) { + return nsLayoutUtils::GetPrimaryFrameFromStyleFrame( + const_cast<nsIFrame*>(aStyleFrame)); +} + +/*static*/ +bool nsLayoutUtils::IsPrimaryStyleFrame(const nsIFrame* aFrame) { + if (aFrame->IsTableWrapperFrame()) { + return false; + } + + const nsIFrame* parent = aFrame->GetParent(); + if (parent && parent->IsTableWrapperFrame()) { + return parent->PrincipalChildList().FirstChild() == aFrame; + } + + return aFrame->IsPrimaryFrame(); +} + +nsIFrame* nsLayoutUtils::GetFloatFromPlaceholder(nsIFrame* aFrame) { + NS_ASSERTION(aFrame->IsPlaceholderFrame(), "Must have a placeholder here"); + if (aFrame->HasAnyStateBits(PLACEHOLDER_FOR_FLOAT)) { + nsIFrame* outOfFlowFrame = + nsPlaceholderFrame::GetRealFrameForPlaceholder(aFrame); + NS_ASSERTION(outOfFlowFrame && outOfFlowFrame->IsFloating(), + "How did that happen?"); + return outOfFlowFrame; + } + + return nullptr; +} + +// static +nsIFrame* nsLayoutUtils::GetCrossDocParentFrameInProcess( + const nsIFrame* aFrame, nsPoint* aCrossDocOffset) { + nsIFrame* p = aFrame->GetParent(); + if (p) { + return p; + } + + nsView* v = aFrame->GetView(); + if (!v) { + return nullptr; + } + v = v->GetParent(); // anonymous inner view + if (!v) { + return nullptr; + } + v = v->GetParent(); // subdocumentframe's view + if (!v) { + return nullptr; + } + + p = v->GetFrame(); + if (p && aCrossDocOffset) { + nsSubDocumentFrame* subdocumentFrame = do_QueryFrame(p); + MOZ_ASSERT(subdocumentFrame); + *aCrossDocOffset += subdocumentFrame->GetExtraOffset(); + } + + return p; +} + +// static +nsIFrame* nsLayoutUtils::GetCrossDocParentFrame(const nsIFrame* aFrame, + nsPoint* aCrossDocOffset) { + return GetCrossDocParentFrameInProcess(aFrame, aCrossDocOffset); +} + +// static +bool nsLayoutUtils::IsProperAncestorFrameCrossDoc( + const nsIFrame* aAncestorFrame, const nsIFrame* aFrame, + const nsIFrame* aCommonAncestor) { + if (aFrame == aAncestorFrame) return false; + return IsAncestorFrameCrossDoc(aAncestorFrame, aFrame, aCommonAncestor); +} + +// static +bool nsLayoutUtils::IsProperAncestorFrameCrossDocInProcess( + const nsIFrame* aAncestorFrame, const nsIFrame* aFrame, + const nsIFrame* aCommonAncestor) { + if (aFrame == aAncestorFrame) return false; + return IsAncestorFrameCrossDocInProcess(aAncestorFrame, aFrame, + aCommonAncestor); +} + +// static +bool nsLayoutUtils::IsAncestorFrameCrossDoc(const nsIFrame* aAncestorFrame, + const nsIFrame* aFrame, + const nsIFrame* aCommonAncestor) { + for (const nsIFrame* f = aFrame; f != aCommonAncestor; + f = GetCrossDocParentFrameInProcess(f)) { + if (f == aAncestorFrame) return true; + } + return aCommonAncestor == aAncestorFrame; +} + +// static +bool nsLayoutUtils::IsAncestorFrameCrossDocInProcess( + const nsIFrame* aAncestorFrame, const nsIFrame* aFrame, + const nsIFrame* aCommonAncestor) { + for (const nsIFrame* f = aFrame; f != aCommonAncestor; + f = GetCrossDocParentFrameInProcess(f)) { + if (f == aAncestorFrame) return true; + } + return aCommonAncestor == aAncestorFrame; +} + +// static +bool nsLayoutUtils::IsProperAncestorFrame(const nsIFrame* aAncestorFrame, + const nsIFrame* aFrame, + const nsIFrame* aCommonAncestor) { + if (aFrame == aAncestorFrame) return false; + for (const nsIFrame* f = aFrame; f != aCommonAncestor; f = f->GetParent()) { + if (f == aAncestorFrame) return true; + } + return aCommonAncestor == aAncestorFrame; +} + +// static +int32_t nsLayoutUtils::DoCompareTreePosition( + nsIContent* aContent1, nsIContent* aContent2, int32_t aIf1Ancestor, + int32_t aIf2Ancestor, const nsIContent* aCommonAncestor) { + MOZ_ASSERT(aIf1Ancestor == -1 || aIf1Ancestor == 0 || aIf1Ancestor == 1); + MOZ_ASSERT(aIf2Ancestor == -1 || aIf2Ancestor == 0 || aIf2Ancestor == 1); + MOZ_ASSERT(aContent1, "aContent1 must not be null"); + MOZ_ASSERT(aContent2, "aContent2 must not be null"); + + AutoTArray<nsIContent*, 32> content1Ancestors; + nsIContent* c1; + for (c1 = aContent1; c1 && c1 != aCommonAncestor; + c1 = c1->GetFlattenedTreeParent()) { + content1Ancestors.AppendElement(c1); + } + if (!c1 && aCommonAncestor) { + // So, it turns out aCommonAncestor was not an ancestor of c1. Oops. + // Never mind. We can continue as if aCommonAncestor was null. + aCommonAncestor = nullptr; + } + + AutoTArray<nsIContent*, 32> content2Ancestors; + nsIContent* c2; + for (c2 = aContent2; c2 && c2 != aCommonAncestor; + c2 = c2->GetFlattenedTreeParent()) { + content2Ancestors.AppendElement(c2); + } + if (!c2 && aCommonAncestor) { + // So, it turns out aCommonAncestor was not an ancestor of c2. + // We need to retry with no common ancestor hint. + return DoCompareTreePosition(aContent1, aContent2, aIf1Ancestor, + aIf2Ancestor, nullptr); + } + + int last1 = content1Ancestors.Length() - 1; + int last2 = content2Ancestors.Length() - 1; + nsIContent* content1Ancestor = nullptr; + nsIContent* content2Ancestor = nullptr; + while (last1 >= 0 && last2 >= 0 && + ((content1Ancestor = content1Ancestors.ElementAt(last1)) == + (content2Ancestor = content2Ancestors.ElementAt(last2)))) { + last1--; + last2--; + } + + if (last1 < 0) { + if (last2 < 0) { + NS_ASSERTION(aContent1 == aContent2, "internal error?"); + return 0; + } + // aContent1 is an ancestor of aContent2 + return aIf1Ancestor; + } + + if (last2 < 0) { + // aContent2 is an ancestor of aContent1 + return aIf2Ancestor; + } + + // content1Ancestor != content2Ancestor, so they must be siblings with the + // same parent + nsIContent* parent = content1Ancestor->GetFlattenedTreeParent(); +#ifdef DEBUG + // TODO: remove the uglyness, see bug 598468. + NS_ASSERTION(gPreventAssertInCompareTreePosition || parent, + "no common ancestor at all???"); +#endif // DEBUG + if (!parent) { // different documents?? + return 0; + } + + const Maybe<uint32_t> index1 = + parent->ComputeFlatTreeIndexOf(content1Ancestor); + const Maybe<uint32_t> index2 = + parent->ComputeFlatTreeIndexOf(content2Ancestor); + + // None of the nodes are anonymous, just do a regular comparison. + if (index1.isSome() && index2.isSome()) { + return static_cast<int32_t>(static_cast<int64_t>(*index1) - *index2); + } + + // Otherwise handle pseudo-element and anonymous content ordering. + // + // ::marker -> ::before -> anon siblings -> regular siblings -> ::after + auto PseudoIndex = [](const nsINode* aNode, + const Maybe<uint32_t>& aNodeIndex) -> int32_t { + if (aNodeIndex.isSome()) { + return 1; // Not a pseudo. + } + if (aNode->IsContent()) { + if (aNode->AsContent()->IsGeneratedContentContainerForMarker()) { + return -2; + } + if (aNode->AsContent()->IsGeneratedContentContainerForBefore()) { + return -1; + } + if (aNode->AsContent()->IsGeneratedContentContainerForAfter()) { + return 2; + } + } + return 0; + }; + + return PseudoIndex(content1Ancestor, index1) - + PseudoIndex(content2Ancestor, index2); +} + +// static +nsIFrame* nsLayoutUtils::FillAncestors(nsIFrame* aFrame, + nsIFrame* aStopAtAncestor, + nsTArray<nsIFrame*>* aAncestors) { + while (aFrame && aFrame != aStopAtAncestor) { + aAncestors->AppendElement(aFrame); + aFrame = nsLayoutUtils::GetParentOrPlaceholderFor(aFrame); + } + return aFrame; +} + +// Return true if aFrame1 is after aFrame2 +static bool IsFrameAfter(nsIFrame* aFrame1, nsIFrame* aFrame2) { + nsIFrame* f = aFrame2; + do { + f = f->GetNextSibling(); + if (f == aFrame1) return true; + } while (f); + return false; +} + +// static +int32_t nsLayoutUtils::DoCompareTreePosition(nsIFrame* aFrame1, + nsIFrame* aFrame2, + int32_t aIf1Ancestor, + int32_t aIf2Ancestor, + nsIFrame* aCommonAncestor) { + MOZ_ASSERT(aIf1Ancestor == -1 || aIf1Ancestor == 0 || aIf1Ancestor == 1); + MOZ_ASSERT(aIf2Ancestor == -1 || aIf2Ancestor == 0 || aIf2Ancestor == 1); + MOZ_ASSERT(aFrame1, "aFrame1 must not be null"); + MOZ_ASSERT(aFrame2, "aFrame2 must not be null"); + + AutoTArray<nsIFrame*, 20> frame2Ancestors; + nsIFrame* nonCommonAncestor = + FillAncestors(aFrame2, aCommonAncestor, &frame2Ancestors); + + return DoCompareTreePosition(aFrame1, aFrame2, frame2Ancestors, aIf1Ancestor, + aIf2Ancestor, + nonCommonAncestor ? aCommonAncestor : nullptr); +} + +// static +int32_t nsLayoutUtils::DoCompareTreePosition( + nsIFrame* aFrame1, nsIFrame* aFrame2, nsTArray<nsIFrame*>& aFrame2Ancestors, + int32_t aIf1Ancestor, int32_t aIf2Ancestor, nsIFrame* aCommonAncestor) { + MOZ_ASSERT(aIf1Ancestor == -1 || aIf1Ancestor == 0 || aIf1Ancestor == 1); + MOZ_ASSERT(aIf2Ancestor == -1 || aIf2Ancestor == 0 || aIf2Ancestor == 1); + MOZ_ASSERT(aFrame1, "aFrame1 must not be null"); + MOZ_ASSERT(aFrame2, "aFrame2 must not be null"); + + nsPresContext* presContext = aFrame1->PresContext(); + if (presContext != aFrame2->PresContext()) { + NS_ERROR("no common ancestor at all, different documents"); + return 0; + } + + AutoTArray<nsIFrame*, 20> frame1Ancestors; + if (aCommonAncestor && + !FillAncestors(aFrame1, aCommonAncestor, &frame1Ancestors)) { + // We reached the root of the frame tree ... if aCommonAncestor was set, + // it is wrong + return DoCompareTreePosition(aFrame1, aFrame2, aIf1Ancestor, aIf2Ancestor, + nullptr); + } + + int32_t last1 = int32_t(frame1Ancestors.Length()) - 1; + int32_t last2 = int32_t(aFrame2Ancestors.Length()) - 1; + while (last1 >= 0 && last2 >= 0 && + frame1Ancestors[last1] == aFrame2Ancestors[last2]) { + last1--; + last2--; + } + + if (last1 < 0) { + if (last2 < 0) { + NS_ASSERTION(aFrame1 == aFrame2, "internal error?"); + return 0; + } + // aFrame1 is an ancestor of aFrame2 + return aIf1Ancestor; + } + + if (last2 < 0) { + // aFrame2 is an ancestor of aFrame1 + return aIf2Ancestor; + } + + nsIFrame* ancestor1 = frame1Ancestors[last1]; + nsIFrame* ancestor2 = aFrame2Ancestors[last2]; + // Now we should be able to walk sibling chains to find which one is first + if (IsFrameAfter(ancestor2, ancestor1)) return -1; + if (IsFrameAfter(ancestor1, ancestor2)) return 1; + NS_WARNING("Frames were in different child lists???"); + return 0; +} + +// static +nsIFrame* nsLayoutUtils::GetLastSibling(nsIFrame* aFrame) { + if (!aFrame) { + return nullptr; + } + + nsIFrame* next; + while ((next = aFrame->GetNextSibling()) != nullptr) { + aFrame = next; + } + return aFrame; +} + +// static +nsView* nsLayoutUtils::FindSiblingViewFor(nsView* aParentView, + nsIFrame* aFrame) { + nsIFrame* parentViewFrame = aParentView->GetFrame(); + nsIContent* parentViewContent = + parentViewFrame ? parentViewFrame->GetContent() : nullptr; + for (nsView* insertBefore = aParentView->GetFirstChild(); insertBefore; + insertBefore = insertBefore->GetNextSibling()) { + nsIFrame* f = insertBefore->GetFrame(); + if (!f) { + // this view could be some anonymous view attached to a meaningful parent + for (nsView* searchView = insertBefore->GetParent(); searchView; + searchView = searchView->GetParent()) { + f = searchView->GetFrame(); + if (f) { + break; + } + } + NS_ASSERTION(f, "Can't find a frame anywhere!"); + } + if (!f || !aFrame->GetContent() || !f->GetContent() || + CompareTreePosition(aFrame->GetContent(), f->GetContent(), + parentViewContent) > 0) { + // aFrame's content is after f's content (or we just don't know), + // so put our view before f's view + return insertBefore; + } + } + return nullptr; +} + +// static +nsIScrollableFrame* nsLayoutUtils::GetScrollableFrameFor( + const nsIFrame* aScrolledFrame) { + nsIFrame* frame = aScrolledFrame->GetParent(); + nsIScrollableFrame* sf = do_QueryFrame(frame); + return (sf && sf->GetScrolledFrame() == aScrolledFrame) ? sf : nullptr; +} + +/* static */ +SideBits nsLayoutUtils::GetSideBitsForFixedPositionContent( + const nsIFrame* aFixedPosFrame) { + SideBits sides = SideBits::eNone; + if (aFixedPosFrame) { + const nsStylePosition* position = aFixedPosFrame->StylePosition(); + if (!position->mOffset.Get(eSideRight).IsAuto()) { + sides |= SideBits::eRight; + } + if (!position->mOffset.Get(eSideLeft).IsAuto()) { + sides |= SideBits::eLeft; + } + if (!position->mOffset.Get(eSideBottom).IsAuto()) { + sides |= SideBits::eBottom; + } + if (!position->mOffset.Get(eSideTop).IsAuto()) { + sides |= SideBits::eTop; + } + } + return sides; +} + +ScrollableLayerGuid::ViewID nsLayoutUtils::ScrollIdForRootScrollFrame( + nsPresContext* aPresContext) { + ViewID id = ScrollableLayerGuid::NULL_SCROLL_ID; + if (nsIFrame* rootScrollFrame = + aPresContext->PresShell()->GetRootScrollFrame()) { + if (nsIContent* content = rootScrollFrame->GetContent()) { + id = FindOrCreateIDFor(content); + } + } + return id; +} + +// static +nsIScrollableFrame* nsLayoutUtils::GetNearestScrollableFrameForDirection( + nsIFrame* aFrame, ScrollDirections aDirections) { + NS_ASSERTION( + aFrame, "GetNearestScrollableFrameForDirection expects a non-null frame"); + // FIXME Bug 1714720 : This nearest scroll target is not going to work over + // process boundaries, in such cases we need to hand over in APZ side. + for (nsIFrame* f = aFrame; f; + f = nsLayoutUtils::GetCrossDocParentFrameInProcess(f)) { + nsIScrollableFrame* scrollableFrame = do_QueryFrame(f); + if (scrollableFrame) { + ScrollDirections directions = + scrollableFrame->GetAvailableScrollingDirectionsForUserInputEvents(); + if (aDirections.contains(ScrollDirection::eVertical)) { + if (directions.contains(ScrollDirection::eVertical)) { + return scrollableFrame; + } + } + if (aDirections.contains(ScrollDirection::eHorizontal)) { + if (directions.contains(ScrollDirection::eHorizontal)) { + return scrollableFrame; + } + } + } + } + return nullptr; +} + +static nsIFrame* GetNearestScrollableOrOverflowClipFrame( + nsIFrame* aFrame, uint32_t aFlags, + const std::function<bool(const nsIFrame* aCurrentFrame)>& aClipFrameCheck = + nullptr) { + MOZ_ASSERT( + aFrame, + "GetNearestScrollableOrOverflowClipFrame expects a non-null frame"); + + auto GetNextFrame = [aFlags](const nsIFrame* aFrame) -> nsIFrame* { + return (aFlags & nsLayoutUtils::SCROLLABLE_SAME_DOC) + ? aFrame->GetParent() + : nsLayoutUtils::GetCrossDocParentFrameInProcess(aFrame); + }; + + for (nsIFrame* f = aFrame; f; f = GetNextFrame(f)) { + if (aClipFrameCheck && aClipFrameCheck(f)) { + return f; + } + + if ((aFlags & nsLayoutUtils::SCROLLABLE_STOP_AT_PAGE) && f->IsPageFrame()) { + break; + } + if (nsIScrollableFrame* scrollableFrame = do_QueryFrame(f)) { + if (aFlags & nsLayoutUtils::SCROLLABLE_ONLY_ASYNC_SCROLLABLE) { + if (scrollableFrame->WantAsyncScroll()) { + return f; + } + } else { + ScrollStyles ss = scrollableFrame->GetScrollStyles(); + if ((aFlags & nsLayoutUtils::SCROLLABLE_INCLUDE_HIDDEN) || + ss.mVertical != StyleOverflow::Hidden || + ss.mHorizontal != StyleOverflow::Hidden) { + return f; + } + } + if (aFlags & nsLayoutUtils::SCROLLABLE_ALWAYS_MATCH_ROOT) { + PresShell* presShell = f->PresShell(); + if (presShell->GetRootScrollFrame() == f && presShell->GetDocument() && + presShell->GetDocument()->IsRootDisplayDocument()) { + return f; + } + } + } + if ((aFlags & nsLayoutUtils::SCROLLABLE_FIXEDPOS_FINDS_ROOT) && + f->StyleDisplay()->mPosition == StylePositionProperty::Fixed && + nsLayoutUtils::IsReallyFixedPos(f)) { + return f->PresShell()->GetRootScrollFrame(); + } + } + return nullptr; +} + +// static +nsIScrollableFrame* nsLayoutUtils::GetNearestScrollableFrame(nsIFrame* aFrame, + uint32_t aFlags) { + nsIFrame* found = GetNearestScrollableOrOverflowClipFrame(aFrame, aFlags); + if (!found) { + return nullptr; + } + + return do_QueryFrame(found); +} + +// static +nsIFrame* nsLayoutUtils::GetNearestOverflowClipFrame(nsIFrame* aFrame) { + return GetNearestScrollableOrOverflowClipFrame( + aFrame, SCROLLABLE_SAME_DOC | SCROLLABLE_INCLUDE_HIDDEN, + [](const nsIFrame* currentFrame) -> bool { + // In cases of SVG Inner/Outer frames it basically clips descendants + // unless overflow: visible is explicitly specified. + LayoutFrameType type = currentFrame->Type(); + return ((type == LayoutFrameType::SVGOuterSVG || + type == LayoutFrameType::SVGInnerSVG) && + (currentFrame->StyleDisplay()->mOverflowX != + StyleOverflow::Visible && + currentFrame->StyleDisplay()->mOverflowY != + StyleOverflow::Visible)); + }); +} + +// static +nsRect nsLayoutUtils::GetScrolledRect(nsIFrame* aScrolledFrame, + const nsRect& aScrolledFrameOverflowArea, + const nsSize& aScrollPortSize, + StyleDirection aDirection) { + WritingMode wm = aScrolledFrame->GetWritingMode(); + // Potentially override the frame's direction to use the direction found + // by ScrollFrameHelper::GetScrolledFrameDir() + wm.SetDirectionFromBidiLevel(aDirection == StyleDirection::Rtl + ? mozilla::intl::BidiEmbeddingLevel::RTL() + : mozilla::intl::BidiEmbeddingLevel::LTR()); + + nscoord x1 = aScrolledFrameOverflowArea.x, + x2 = aScrolledFrameOverflowArea.XMost(), + y1 = aScrolledFrameOverflowArea.y, + y2 = aScrolledFrameOverflowArea.YMost(); + + const bool isHorizontalWM = !wm.IsVertical(); + const bool isVerticalWM = wm.IsVertical(); + bool isInlineFlowFromTopOrLeft = !wm.IsInlineReversed(); + bool isBlockFlowFromTopOrLeft = isHorizontalWM || wm.IsVerticalLR(); + + if (aScrolledFrame->IsFlexContainerFrame()) { + // In a flex container, the children flow (and overflow) along the flex + // container's main axis and cross axis. These are analogous to the + // inline/block axes, and by default they correspond exactly to those axes; + // but the flex container's CSS (e.g. flex-direction: column-reverse) may + // have swapped and/or reversed them, and we need to account for that here. + FlexboxAxisInfo info(aScrolledFrame); + if (info.mIsRowOriented) { + // The flex container's inline axis is the main axis. + isInlineFlowFromTopOrLeft = + isInlineFlowFromTopOrLeft == !info.mIsMainAxisReversed; + isBlockFlowFromTopOrLeft = + isBlockFlowFromTopOrLeft == !info.mIsCrossAxisReversed; + } else { + // The flex container's block axis is the main axis. + isBlockFlowFromTopOrLeft = + isBlockFlowFromTopOrLeft == !info.mIsMainAxisReversed; + isInlineFlowFromTopOrLeft = + isInlineFlowFromTopOrLeft == !info.mIsCrossAxisReversed; + } + } + + // Clamp the horizontal start-edge (x1 or x2, depending whether the logical + // axis that corresponds to horizontal progresses from left-to-right or + // right-to-left). + if ((isHorizontalWM && isInlineFlowFromTopOrLeft) || + (isVerticalWM && isBlockFlowFromTopOrLeft)) { + if (x1 < 0) { + x1 = 0; + } + } else { + if (x2 > aScrollPortSize.width) { + x2 = aScrollPortSize.width; + } + // When the scrolled frame chooses a size larger than its available width + // (because its padding alone is larger than the available width), we need + // to keep the start-edge of the scroll frame anchored to the start-edge of + // the scrollport. + // When the scrolled frame is RTL, this means moving it in our left-based + // coordinate system, so we need to compensate for its extra width here by + // effectively repositioning the frame. + nscoord extraWidth = + std::max(0, aScrolledFrame->GetSize().width - aScrollPortSize.width); + x2 += extraWidth; + } + + // Similarly, clamp the vertical start-edge (y1 or y2, depending whether the + // logical axis that corresponds to vertical progresses from top-to-bottom or + // buttom-to-top). + if ((isHorizontalWM && isBlockFlowFromTopOrLeft) || + (isVerticalWM && isInlineFlowFromTopOrLeft)) { + if (y1 < 0) { + y1 = 0; + } + } else { + if (y2 > aScrollPortSize.height) { + y2 = aScrollPortSize.height; + } + nscoord extraHeight = + std::max(0, aScrolledFrame->GetSize().height - aScrollPortSize.height); + y2 += extraHeight; + } + + return nsRect(x1, y1, x2 - x1, y2 - y1); +} + +// static +bool nsLayoutUtils::HasPseudoStyle(nsIContent* aContent, + ComputedStyle* aComputedStyle, + PseudoStyleType aPseudoElement, + nsPresContext* aPresContext) { + MOZ_ASSERT(aPresContext, "Must have a prescontext"); + + RefPtr<ComputedStyle> pseudoContext; + if (aContent) { + pseudoContext = aPresContext->StyleSet()->ProbePseudoElementStyle( + *aContent->AsElement(), aPseudoElement, aComputedStyle); + } + return pseudoContext != nullptr; +} + +nsPoint nsLayoutUtils::GetDOMEventCoordinatesRelativeTo(Event* aDOMEvent, + nsIFrame* aFrame) { + if (!aDOMEvent) return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + WidgetEvent* event = aDOMEvent->WidgetEventPtr(); + if (!event) return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + return GetEventCoordinatesRelativeTo(event, RelativeTo{aFrame}); +} + +static bool IsValidCoordinateTypeEvent(const WidgetEvent* aEvent) { + if (!aEvent) { + return false; + } + return aEvent->mClass == eMouseEventClass || + aEvent->mClass == eMouseScrollEventClass || + aEvent->mClass == eWheelEventClass || + aEvent->mClass == eDragEventClass || + aEvent->mClass == eSimpleGestureEventClass || + aEvent->mClass == ePointerEventClass || + aEvent->mClass == eGestureNotifyEventClass || + aEvent->mClass == eTouchEventClass || + aEvent->mClass == eQueryContentEventClass; +} + +nsPoint nsLayoutUtils::GetEventCoordinatesRelativeTo(const WidgetEvent* aEvent, + RelativeTo aFrame) { + if (!IsValidCoordinateTypeEvent(aEvent)) { + return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + } + + return GetEventCoordinatesRelativeTo(aEvent, aEvent->AsGUIEvent()->mRefPoint, + aFrame); +} + +nsPoint nsLayoutUtils::GetEventCoordinatesRelativeTo( + const WidgetEvent* aEvent, const LayoutDeviceIntPoint& aPoint, + RelativeTo aFrame) { + if (!aFrame.mFrame) { + return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + } + + nsIWidget* widget = aEvent->AsGUIEvent()->mWidget; + if (!widget) { + return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + } + + return GetEventCoordinatesRelativeTo(widget, aPoint, aFrame); +} + +nsPoint GetEventCoordinatesRelativeTo(nsIWidget* aWidget, + const LayoutDeviceIntPoint& aPoint, + RelativeTo aFrame) { + const nsIFrame* frame = aFrame.mFrame; + if (!frame || !aWidget) { + return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + } + + nsView* view = frame->GetView(); + if (view) { + nsIWidget* frameWidget = view->GetWidget(); + if (frameWidget && frameWidget == aWidget) { + // Special case this cause it happens a lot. + // This also fixes bug 664707, events in the extra-special case of select + // dropdown popups that are transformed. + nsPresContext* presContext = frame->PresContext(); + nsPoint pt(presContext->DevPixelsToAppUnits(aPoint.x), + presContext->DevPixelsToAppUnits(aPoint.y)); + return pt - view->ViewToWidgetOffset(); + } + } + + /* If we walk up the frame tree and discover that any of the frames are + * transformed, we need to do extra work to convert from the global + * space to the local space. + */ + const nsIFrame* rootFrame = frame; + bool transformFound = false; + for (const nsIFrame* f = frame; f; + f = nsLayoutUtils::GetCrossDocParentFrameInProcess(f)) { + if (f->IsTransformed() || ViewportUtils::IsZoomedContentRoot(f)) { + transformFound = true; + } + + rootFrame = f; + } + + nsView* rootView = rootFrame->GetView(); + if (!rootView) { + return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + } + + nsPoint widgetToView = nsLayoutUtils::TranslateWidgetToView( + rootFrame->PresContext(), aWidget, aPoint, rootView); + + if (widgetToView == nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE)) { + return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + } + + // Convert from root document app units to app units of the document aFrame + // is in. + int32_t rootAPD = rootFrame->PresContext()->AppUnitsPerDevPixel(); + int32_t localAPD = frame->PresContext()->AppUnitsPerDevPixel(); + widgetToView = widgetToView.ScaleToOtherAppUnits(rootAPD, localAPD); + + /* If we encountered a transform, we can't do simple arithmetic to figure + * out how to convert back to aFrame's coordinates and must use the CTM. + */ + if (transformFound || SVGUtils::IsInSVGTextSubtree(frame)) { + return nsLayoutUtils::TransformRootPointToFrame(ViewportType::Visual, + aFrame, widgetToView); + } + + /* Otherwise, all coordinate systems are translations of one another, + * so we can just subtract out the difference. + */ + return widgetToView - frame->GetOffsetToCrossDoc(rootFrame); +} + +nsPoint nsLayoutUtils::GetEventCoordinatesRelativeTo( + nsIWidget* aWidget, const LayoutDeviceIntPoint& aPoint, RelativeTo aFrame) { + nsPoint result = ::GetEventCoordinatesRelativeTo(aWidget, aPoint, aFrame); + if (aFrame.mViewportType == ViewportType::Layout && aFrame.mFrame && + aFrame.mFrame->Type() == LayoutFrameType::Viewport && + aFrame.mFrame->PresContext()->IsRootContentDocumentCrossProcess()) { + result = ViewportUtils::VisualToLayout(result, aFrame.mFrame->PresShell()); + } + return result; +} + +nsIFrame* nsLayoutUtils::GetPopupFrameForEventCoordinates( + nsPresContext* aRootPresContext, const WidgetEvent* aEvent) { + if (!IsValidCoordinateTypeEvent(aEvent)) { + return nullptr; + } + + const auto* guiEvent = aEvent->AsGUIEvent(); + return GetPopupFrameForPoint(aRootPresContext, guiEvent->mWidget, + guiEvent->mRefPoint); +} + +nsIFrame* nsLayoutUtils::GetPopupFrameForPoint( + nsPresContext* aRootPresContext, nsIWidget* aWidget, + const mozilla::LayoutDeviceIntPoint& aPoint, + GetPopupFrameForPointFlags aFlags /* = GetPopupFrameForPointFlags(0) */) { + nsXULPopupManager* pm = nsXULPopupManager::GetInstance(); + if (!pm) { + return nullptr; + } + nsTArray<nsIFrame*> popups; + pm->GetVisiblePopups(popups); + // Search from top to bottom + for (nsIFrame* popup : popups) { + if (popup->PresContext()->GetRootPresContext() != aRootPresContext) { + continue; + } + if (!popup->ScrollableOverflowRect().Contains(GetEventCoordinatesRelativeTo( + aWidget, aPoint, RelativeTo{popup}))) { + continue; + } + if (aFlags & GetPopupFrameForPointFlags::OnlyReturnFramesWithWidgets) { + if (!popup->HasView() || !popup->GetView()->HasWidget()) { + continue; + } + } + return popup; + } + return nullptr; +} + +void nsLayoutUtils::GetContainerAndOffsetAtEvent(PresShell* aPresShell, + const WidgetEvent* aEvent, + nsIContent** aContainer, + int32_t* aOffset) { + MOZ_ASSERT(aContainer || aOffset); + + if (aContainer) { + *aContainer = nullptr; + } + if (aOffset) { + *aOffset = 0; + } + + if (!aPresShell) { + return; + } + + aPresShell->FlushPendingNotifications(FlushType::Layout); + + RefPtr<nsPresContext> presContext = aPresShell->GetPresContext(); + if (!presContext) { + return; + } + + nsIFrame* targetFrame = presContext->EventStateManager()->GetEventTarget(); + if (!targetFrame) { + return; + } + + WidgetEvent* openingEvent = nullptr; + // For popupshowing events, redirect via the original mouse event + // that triggered the popup to open. + if (aEvent->mMessage == eXULPopupShowing) { + if (auto* pm = nsXULPopupManager::GetInstance()) { + if (Event* openingPopupEvent = pm->GetOpeningPopupEvent()) { + openingEvent = openingPopupEvent->WidgetEventPtr(); + } + } + } + + nsPoint point = nsLayoutUtils::GetEventCoordinatesRelativeTo( + openingEvent ? openingEvent : aEvent, RelativeTo{targetFrame}); + + if (aContainer) { + // TODO: This result may be useful to change to Selection. However, this + // may return improper node (e.g., native anonymous node) for the + // Selection. Perhaps, this should take Selection optionally and + // if it's specified, needs to check if it's proper for the + // Selection. + nsCOMPtr<nsIContent> container = + targetFrame->GetContentOffsetsFromPoint(point).content; + if (container && (!container->ChromeOnlyAccess() || + nsContentUtils::CanAccessNativeAnon())) { + container.forget(aContainer); + } + } + if (aOffset) { + *aOffset = targetFrame->GetContentOffsetsFromPoint(point).offset; + } +} + +void nsLayoutUtils::ConstrainToCoordValues(float& aStart, float& aSize) { + MOZ_ASSERT(aSize >= 0); + + // Here we try to make sure that the resulting nsRect will continue to cover + // as much of the area that was covered by the original gfx Rect as possible. + + // We clamp the bounds of the rect to {nscoord_MIN,nscoord_MAX} since + // nsRect::X/Y() and nsRect::XMost/YMost() can't return values outwith this + // range: + float end = aStart + aSize; + aStart = clamped(aStart, float(nscoord_MIN), float(nscoord_MAX)); + end = clamped(end, float(nscoord_MIN), float(nscoord_MAX)); + + aSize = end - aStart; + + // We must also clamp aSize to {0,nscoord_MAX} since nsRect::Width/Height() + // can't return a value greater than nscoord_MAX. If aSize is greater than + // nscoord_MAX then we reduce it to nscoord_MAX while keeping the rect + // centered: + if (MOZ_UNLIKELY(std::isnan(aSize))) { + // Can happen if aStart is -inf and aSize is +inf for example. + aStart = 0.0f; + aSize = float(nscoord_MAX); + } else if (aSize > float(nscoord_MAX)) { + float excess = aSize - float(nscoord_MAX); + excess /= 2; + aStart += excess; + aSize = float(nscoord_MAX); + } +} + +/** + * Given a gfxFloat, constrains its value to be between nscoord_MIN and + * nscoord_MAX. + * + * @param aVal The value to constrain (in/out) + */ +static void ConstrainToCoordValues(gfxFloat& aVal) { + if (aVal <= nscoord_MIN) + aVal = nscoord_MIN; + else if (aVal >= nscoord_MAX) + aVal = nscoord_MAX; +} + +void nsLayoutUtils::ConstrainToCoordValues(gfxFloat& aStart, gfxFloat& aSize) { + gfxFloat max = aStart + aSize; + + // Clamp the end points to within nscoord range + ::ConstrainToCoordValues(aStart); + ::ConstrainToCoordValues(max); + + aSize = max - aStart; + // If the width if still greater than the max nscoord, then bring both + // endpoints in by the same amount until it fits. + if (MOZ_UNLIKELY(std::isnan(aSize))) { + // Can happen if aStart is -inf and aSize is +inf for example. + aStart = 0.0f; + aSize = nscoord_MAX; + } else if (aSize > nscoord_MAX) { + gfxFloat excess = aSize - nscoord_MAX; + excess /= 2; + + aStart += excess; + aSize = nscoord_MAX; + } else if (aSize < nscoord_MIN) { + gfxFloat excess = aSize - nscoord_MIN; + excess /= 2; + + aStart -= excess; + aSize = nscoord_MIN; + } +} + +nsRegion nsLayoutUtils::RoundedRectIntersectRect(const nsRect& aRoundedRect, + const nscoord aRadii[8], + const nsRect& aContainedRect) { + // rectFullHeight and rectFullWidth together will approximately contain + // the total area of the frame minus the rounded corners. + nsRect rectFullHeight = aRoundedRect; + nscoord xDiff = std::max(aRadii[eCornerTopLeftX], aRadii[eCornerBottomLeftX]); + rectFullHeight.x += xDiff; + rectFullHeight.width -= + std::max(aRadii[eCornerTopRightX], aRadii[eCornerBottomRightX]) + xDiff; + nsRect r1; + r1.IntersectRect(rectFullHeight, aContainedRect); + + nsRect rectFullWidth = aRoundedRect; + nscoord yDiff = std::max(aRadii[eCornerTopLeftY], aRadii[eCornerTopRightY]); + rectFullWidth.y += yDiff; + rectFullWidth.height -= + std::max(aRadii[eCornerBottomLeftY], aRadii[eCornerBottomRightY]) + yDiff; + nsRect r2; + r2.IntersectRect(rectFullWidth, aContainedRect); + + nsRegion result; + result.Or(r1, r2); + return result; +} + +nsIntRegion nsLayoutUtils::RoundedRectIntersectIntRect( + const nsIntRect& aRoundedRect, const RectCornerRadii& aCornerRadii, + const nsIntRect& aContainedRect) { + // rectFullHeight and rectFullWidth together will approximately contain + // the total area of the frame minus the rounded corners. + nsIntRect rectFullHeight = aRoundedRect; + uint32_t xDiff = + std::max(aCornerRadii.TopLeft().width, aCornerRadii.BottomLeft().width); + rectFullHeight.x += xDiff; + rectFullHeight.width -= std::max(aCornerRadii.TopRight().width, + aCornerRadii.BottomRight().width) + + xDiff; + nsIntRect r1; + r1.IntersectRect(rectFullHeight, aContainedRect); + + nsIntRect rectFullWidth = aRoundedRect; + uint32_t yDiff = + std::max(aCornerRadii.TopLeft().height, aCornerRadii.TopRight().height); + rectFullWidth.y += yDiff; + rectFullWidth.height -= std::max(aCornerRadii.BottomLeft().height, + aCornerRadii.BottomRight().height) + + yDiff; + nsIntRect r2; + r2.IntersectRect(rectFullWidth, aContainedRect); + + nsIntRegion result; + result.Or(r1, r2); + return result; +} + +// Helper for RoundedRectIntersectsRect. +static bool CheckCorner(nscoord aXOffset, nscoord aYOffset, nscoord aXRadius, + nscoord aYRadius) { + MOZ_ASSERT(aXOffset > 0 && aYOffset > 0, + "must not pass nonpositives to CheckCorner"); + MOZ_ASSERT(aXRadius >= 0 && aYRadius >= 0, + "must not pass negatives to CheckCorner"); + + // Avoid floating point math unless we're either (1) within the + // quarter-ellipse area at the rounded corner or (2) outside the + // rounding. + if (aXOffset >= aXRadius || aYOffset >= aYRadius) return true; + + // Convert coordinates to a unit circle with (0,0) as the center of + // curvature, and see if we're inside the circle or outside. + float scaledX = float(aXRadius - aXOffset) / float(aXRadius); + float scaledY = float(aYRadius - aYOffset) / float(aYRadius); + return scaledX * scaledX + scaledY * scaledY < 1.0f; +} + +bool nsLayoutUtils::RoundedRectIntersectsRect(const nsRect& aRoundedRect, + const nscoord aRadii[8], + const nsRect& aTestRect) { + if (!aTestRect.Intersects(aRoundedRect)) return false; + + // distances from this edge of aRoundedRect to opposite edge of aTestRect, + // which we know are positive due to the Intersects check above. + nsMargin insets; + insets.top = aTestRect.YMost() - aRoundedRect.y; + insets.right = aRoundedRect.XMost() - aTestRect.x; + insets.bottom = aRoundedRect.YMost() - aTestRect.y; + insets.left = aTestRect.XMost() - aRoundedRect.x; + + // Check whether the bottom-right corner of aTestRect is inside the + // top left corner of aBounds when rounded by aRadii, etc. If any + // corner is not, then fail; otherwise succeed. + return CheckCorner(insets.left, insets.top, aRadii[eCornerTopLeftX], + aRadii[eCornerTopLeftY]) && + CheckCorner(insets.right, insets.top, aRadii[eCornerTopRightX], + aRadii[eCornerTopRightY]) && + CheckCorner(insets.right, insets.bottom, aRadii[eCornerBottomRightX], + aRadii[eCornerBottomRightY]) && + CheckCorner(insets.left, insets.bottom, aRadii[eCornerBottomLeftX], + aRadii[eCornerBottomLeftY]); +} + +nsRect nsLayoutUtils::MatrixTransformRect(const nsRect& aBounds, + const Matrix4x4& aMatrix, + float aFactor) { + RectDouble image = + RectDouble(NSAppUnitsToDoublePixels(aBounds.x, aFactor), + NSAppUnitsToDoublePixels(aBounds.y, aFactor), + NSAppUnitsToDoublePixels(aBounds.width, aFactor), + NSAppUnitsToDoublePixels(aBounds.height, aFactor)); + + RectDouble maxBounds = RectDouble( + double(nscoord_MIN) / aFactor * 0.5, double(nscoord_MIN) / aFactor * 0.5, + double(nscoord_MAX) / aFactor, double(nscoord_MAX) / aFactor); + + image = aMatrix.TransformAndClipBounds(image, maxBounds); + + return RoundGfxRectToAppRect(ThebesRect(image), aFactor); +} + +nsRect nsLayoutUtils::MatrixTransformRect(const nsRect& aBounds, + const Matrix4x4Flagged& aMatrix, + float aFactor) { + RectDouble image = + RectDouble(NSAppUnitsToDoublePixels(aBounds.x, aFactor), + NSAppUnitsToDoublePixels(aBounds.y, aFactor), + NSAppUnitsToDoublePixels(aBounds.width, aFactor), + NSAppUnitsToDoublePixels(aBounds.height, aFactor)); + + RectDouble maxBounds = RectDouble( + double(nscoord_MIN) / aFactor * 0.5, double(nscoord_MIN) / aFactor * 0.5, + double(nscoord_MAX) / aFactor, double(nscoord_MAX) / aFactor); + + image = aMatrix.TransformAndClipBounds(image, maxBounds); + + return RoundGfxRectToAppRect(ThebesRect(image), aFactor); +} + +nsPoint nsLayoutUtils::MatrixTransformPoint(const nsPoint& aPoint, + const Matrix4x4& aMatrix, + float aFactor) { + gfxPoint image = gfxPoint(NSAppUnitsToFloatPixels(aPoint.x, aFactor), + NSAppUnitsToFloatPixels(aPoint.y, aFactor)); + image = aMatrix.TransformPoint(image); + return nsPoint(NSFloatPixelsToAppUnits(float(image.x), aFactor), + NSFloatPixelsToAppUnits(float(image.y), aFactor)); +} + +void nsLayoutUtils::PostTranslate(Matrix4x4& aTransform, const nsPoint& aOrigin, + float aAppUnitsPerPixel, bool aRounded) { + Point3D gfxOrigin = + Point3D(NSAppUnitsToFloatPixels(aOrigin.x, aAppUnitsPerPixel), + NSAppUnitsToFloatPixels(aOrigin.y, aAppUnitsPerPixel), 0.0f); + if (aRounded) { + gfxOrigin.x = NS_round(gfxOrigin.x); + gfxOrigin.y = NS_round(gfxOrigin.y); + } + aTransform.PostTranslate(gfxOrigin); +} + +bool nsLayoutUtils::ShouldSnapToGrid(const nsIFrame* aFrame) { + return !aFrame || !aFrame->HasAnyStateBits(NS_FRAME_SVG_LAYOUT) || + aFrame->IsSVGOuterSVGAnonChildFrame(); +} + +Matrix4x4Flagged nsLayoutUtils::GetTransformToAncestor( + RelativeTo aFrame, RelativeTo aAncestor, uint32_t aFlags, + nsIFrame** aOutAncestor) { + nsIFrame* parent; + Matrix4x4Flagged ctm; + // Make sure we don't get an invalid combination of source and destination + // RelativeTo values. + MOZ_ASSERT(!(aFrame.mViewportType == ViewportType::Visual && + aAncestor.mViewportType == ViewportType::Layout)); + if (aFrame == aAncestor) { + return ctm; + } + ctm = aFrame.mFrame->GetTransformMatrix(aFrame.mViewportType, aAncestor, + &parent, aFlags); + if (!aFrame.mFrame->Combines3DTransformWithAncestors()) { + ctm.ProjectTo2D(); + } + while (parent && parent != aAncestor.mFrame && + (!(aFlags & nsIFrame::STOP_AT_STACKING_CONTEXT_AND_DISPLAY_PORT) || + (!parent->IsStackingContext() && + !DisplayPortUtils::FrameHasDisplayPort(parent)))) { + nsIFrame* cur = parent; + ctm = ctm * cur->GetTransformMatrix(aFrame.mViewportType, aAncestor, + &parent, aFlags); + if (!cur->Combines3DTransformWithAncestors()) { + ctm.ProjectTo2D(); + } + } + if (aOutAncestor) { + *aOutAncestor = parent; + } + return ctm; +} + +MatrixScales nsLayoutUtils::GetTransformToAncestorScale( + const nsIFrame* aFrame) { + Matrix4x4Flagged transform = GetTransformToAncestor( + RelativeTo{aFrame}, + RelativeTo{nsLayoutUtils::GetDisplayRootFrame(aFrame)}); + Matrix transform2D; + if (transform.CanDraw2D(&transform2D)) { + return ThebesMatrix(transform2D).ScaleFactors().ConvertTo<float>(); + } + return MatrixScales(); +} + +static Matrix4x4Flagged GetTransformToAncestorExcludingAnimated( + nsIFrame* aFrame, const nsIFrame* aAncestor) { + nsIFrame* parent; + Matrix4x4Flagged ctm; + if (aFrame == aAncestor) { + return ctm; + } + if (ActiveLayerTracker::IsScaleSubjectToAnimation(aFrame)) { + return ctm; + } + ctm = aFrame->GetTransformMatrix(ViewportType::Layout, RelativeTo{aAncestor}, + &parent); + while (parent && parent != aAncestor) { + if (ActiveLayerTracker::IsScaleSubjectToAnimation(parent)) { + return Matrix4x4Flagged(); + } + if (!parent->Extend3DContext()) { + ctm.ProjectTo2D(); + } + ctm = ctm * parent->GetTransformMatrix(ViewportType::Layout, + RelativeTo{aAncestor}, &parent); + } + return ctm; +} + +MatrixScales nsLayoutUtils::GetTransformToAncestorScaleExcludingAnimated( + nsIFrame* aFrame) { + Matrix4x4Flagged transform = GetTransformToAncestorExcludingAnimated( + aFrame, nsLayoutUtils::GetDisplayRootFrame(aFrame)); + Matrix transform2D; + if (transform.Is2D(&transform2D)) { + return ThebesMatrix(transform2D).ScaleFactors().ConvertTo<float>(); + } + return MatrixScales(); +} + +const nsIFrame* nsLayoutUtils::FindNearestCommonAncestorFrame( + const nsIFrame* aFrame1, const nsIFrame* aFrame2) { + AutoTArray<const nsIFrame*, 100> ancestors1; + AutoTArray<const nsIFrame*, 100> ancestors2; + const nsIFrame* commonAncestor = nullptr; + if (aFrame1->PresContext() == aFrame2->PresContext()) { + commonAncestor = aFrame1->PresShell()->GetRootFrame(); + } + for (const nsIFrame* f = aFrame1; f != commonAncestor; + f = nsLayoutUtils::GetCrossDocParentFrameInProcess(f)) { + ancestors1.AppendElement(f); + } + for (const nsIFrame* f = aFrame2; f != commonAncestor; + f = nsLayoutUtils::GetCrossDocParentFrameInProcess(f)) { + ancestors2.AppendElement(f); + } + uint32_t minLengths = std::min(ancestors1.Length(), ancestors2.Length()); + for (uint32_t i = 1; i <= minLengths; ++i) { + if (ancestors1[ancestors1.Length() - i] == + ancestors2[ancestors2.Length() - i]) { + commonAncestor = ancestors1[ancestors1.Length() - i]; + } else { + break; + } + } + return commonAncestor; +} + +const nsIFrame* nsLayoutUtils::FindNearestCommonAncestorFrameWithinBlock( + const nsTextFrame* aFrame1, const nsTextFrame* aFrame2) { + MOZ_ASSERT(aFrame1); + MOZ_ASSERT(aFrame2); + + const nsIFrame* f1 = aFrame1; + const nsIFrame* f2 = aFrame2; + + int n1 = 1; + int n2 = 1; + + for (auto f = f1->GetParent();;) { + NS_ASSERTION(f, "All text frames should have a block ancestor"); + if (!f) { + return nullptr; + } + if (f->IsBlockFrameOrSubclass()) { + break; + } + ++n1; + f = f->GetParent(); + } + + for (auto f = f2->GetParent();;) { + NS_ASSERTION(f, "All text frames should have a block ancestor"); + if (!f) { + return nullptr; + } + if (f->IsBlockFrameOrSubclass()) { + break; + } + ++n2; + f = f->GetParent(); + } + + if (n1 > n2) { + std::swap(n1, n2); + std::swap(f1, f2); + } + + while (n2 > n1) { + f2 = f2->GetParent(); + --n2; + } + + while (n2 >= 0) { + if (f1 == f2) { + return f1; + } + f1 = f1->GetParent(); + f2 = f2->GetParent(); + --n2; + } + + return nullptr; +} + +bool nsLayoutUtils::AuthorSpecifiedBorderBackgroundDisablesTheming( + StyleAppearance aAppearance) { + return aAppearance == StyleAppearance::NumberInput || + aAppearance == StyleAppearance::Button || + aAppearance == StyleAppearance::Textfield || + aAppearance == StyleAppearance::Textarea || + aAppearance == StyleAppearance::Listbox || + aAppearance == StyleAppearance::Menulist || + aAppearance == StyleAppearance::MenulistButton; +} + +static SVGTextFrame* GetContainingSVGTextFrame(const nsIFrame* aFrame) { + if (!SVGUtils::IsInSVGTextSubtree(aFrame)) { + return nullptr; + } + + return static_cast<SVGTextFrame*>(nsLayoutUtils::GetClosestFrameOfType( + aFrame->GetParent(), LayoutFrameType::SVGText)); +} + +static bool TransformGfxPointFromAncestor(RelativeTo aFrame, + const Point& aPoint, + RelativeTo aAncestor, + Maybe<Matrix4x4Flagged>& aMatrixCache, + Point* aOut) { + SVGTextFrame* text = GetContainingSVGTextFrame(aFrame.mFrame); + + if (!aMatrixCache) { + auto matrix = nsLayoutUtils::GetTransformToAncestor( + RelativeTo{text ? text : aFrame.mFrame, aFrame.mViewportType}, + aAncestor); + if (matrix.IsSingular()) { + return false; + } + matrix.Invert(); + aMatrixCache.emplace(matrix); + } + + const Matrix4x4Flagged& ctm = *aMatrixCache; + Point4D point = ctm.ProjectPoint(aPoint); + if (!point.HasPositiveWCoord()) { + return false; + } + + *aOut = point.As2DPoint(); + + if (text) { + *aOut = text->TransformFramePointToTextChild(*aOut, aFrame.mFrame); + } + + return true; +} + +static Point TransformGfxPointToAncestor( + RelativeTo aFrame, const Point& aPoint, RelativeTo aAncestor, + Maybe<Matrix4x4Flagged>& aMatrixCache) { + if (SVGTextFrame* text = GetContainingSVGTextFrame(aFrame.mFrame)) { + Point result = + text->TransformFramePointFromTextChild(aPoint, aFrame.mFrame); + return TransformGfxPointToAncestor(RelativeTo{text}, result, aAncestor, + aMatrixCache); + } + if (!aMatrixCache) { + aMatrixCache.emplace( + nsLayoutUtils::GetTransformToAncestor(aFrame, aAncestor)); + } + return aMatrixCache->ProjectPoint(aPoint).As2DPoint(); +} + +static Rect TransformGfxRectToAncestor( + RelativeTo aFrame, const Rect& aRect, RelativeTo aAncestor, + bool* aPreservesAxisAlignedRectangles = nullptr, + Maybe<Matrix4x4Flagged>* aMatrixCache = nullptr, + bool aStopAtStackingContextAndDisplayPortAndOOFFrame = false, + nsIFrame** aOutAncestor = nullptr) { + Rect result; + Matrix4x4Flagged ctm; + if (SVGTextFrame* text = GetContainingSVGTextFrame(aFrame.mFrame)) { + result = text->TransformFrameRectFromTextChild(aRect, aFrame.mFrame); + + result = TransformGfxRectToAncestor( + RelativeTo{text}, result, aAncestor, nullptr, aMatrixCache, + aStopAtStackingContextAndDisplayPortAndOOFFrame, aOutAncestor); + if (aPreservesAxisAlignedRectangles) { + // TransformFrameRectFromTextChild could involve any kind of transform, we + // could drill down into it to get an answer out of it but we don't yet. + *aPreservesAxisAlignedRectangles = false; + } + return result; + } + if (aMatrixCache && *aMatrixCache) { + // We are given a matrix to use, so use it + ctm = aMatrixCache->value(); + } else { + // Else, compute it + uint32_t flags = 0; + if (aStopAtStackingContextAndDisplayPortAndOOFFrame) { + flags |= nsIFrame::STOP_AT_STACKING_CONTEXT_AND_DISPLAY_PORT; + } + ctm = nsLayoutUtils::GetTransformToAncestor(aFrame, aAncestor, flags, + aOutAncestor); + if (aMatrixCache) { + // and put it in the cache, if provided + *aMatrixCache = Some(ctm); + } + } + // Fill out the axis-alignment flag + if (aPreservesAxisAlignedRectangles) { + // TransformFrameRectFromTextChild could involve any kind of transform, we + // could drill down into it to get an answer out of it but we don't yet. + Matrix matrix2d; + *aPreservesAxisAlignedRectangles = + ctm.Is2D(&matrix2d) && matrix2d.PreservesAxisAlignedRectangles(); + } + const nsIFrame* ancestor = aOutAncestor ? *aOutAncestor : aAncestor.mFrame; + float factor = ancestor->PresContext()->AppUnitsPerDevPixel(); + Rect maxBounds = + Rect(float(nscoord_MIN) / factor * 0.5, float(nscoord_MIN) / factor * 0.5, + float(nscoord_MAX) / factor, float(nscoord_MAX) / factor); + return ctm.TransformAndClipBounds(aRect, maxBounds); +} + +nsLayoutUtils::TransformResult nsLayoutUtils::TransformPoints( + RelativeTo aFromFrame, RelativeTo aToFrame, uint32_t aPointCount, + CSSPoint* aPoints) { + // Conceptually, {ViewportFrame, Visual} is an ancestor of + // {ViewportFrame, Layout}, so factor that into the nearest ancestor + // computation. + RelativeTo nearestCommonAncestor{ + FindNearestCommonAncestorFrame(aFromFrame.mFrame, aToFrame.mFrame), + aFromFrame.mViewportType == ViewportType::Visual || + aToFrame.mViewportType == ViewportType::Visual + ? ViewportType::Visual + : ViewportType::Layout}; + if (!nearestCommonAncestor.mFrame) { + return NO_COMMON_ANCESTOR; + } + CSSToLayoutDeviceScale devPixelsPerCSSPixelFromFrame = + aFromFrame.mFrame->PresContext()->CSSToDevPixelScale(); + CSSToLayoutDeviceScale devPixelsPerCSSPixelToFrame = + aToFrame.mFrame->PresContext()->CSSToDevPixelScale(); + Maybe<Matrix4x4Flagged> cacheTo; + Maybe<Matrix4x4Flagged> cacheFrom; + for (uint32_t i = 0; i < aPointCount; ++i) { + LayoutDevicePoint devPixels = aPoints[i] * devPixelsPerCSSPixelFromFrame; + // What should the behaviour be if some of the points aren't invertible + // and others are? Just assume all points are for now. + Point toDevPixels = + TransformGfxPointToAncestor(aFromFrame, Point(devPixels.x, devPixels.y), + nearestCommonAncestor, cacheTo); + Point result; + if (!TransformGfxPointFromAncestor( + aToFrame, toDevPixels, nearestCommonAncestor, cacheFrom, &result)) { + return NONINVERTIBLE_TRANSFORM; + } + // Divide here so that when the devPixelsPerCSSPixels are the same, we get + // the correct answer instead of some inaccuracy multiplying a number by its + // reciprocal. + aPoints[i] = + LayoutDevicePoint(result.x, result.y) / devPixelsPerCSSPixelToFrame; + } + return TRANSFORM_SUCCEEDED; +} + +nsLayoutUtils::TransformResult nsLayoutUtils::TransformPoint( + RelativeTo aFromFrame, RelativeTo aToFrame, nsPoint& aPoint) { + CSSPoint point = CSSPoint::FromAppUnits(aPoint); + auto result = TransformPoints(aFromFrame, aToFrame, 1, &point); + if (result == TRANSFORM_SUCCEEDED) { + aPoint = CSSPoint::ToAppUnits(point); + } + return result; +} + +nsLayoutUtils::TransformResult nsLayoutUtils::TransformRect( + const nsIFrame* aFromFrame, const nsIFrame* aToFrame, nsRect& aRect) { + const nsIFrame* nearestCommonAncestor = + FindNearestCommonAncestorFrame(aFromFrame, aToFrame); + if (!nearestCommonAncestor) { + return NO_COMMON_ANCESTOR; + } + Matrix4x4Flagged downToDest = GetTransformToAncestor( + RelativeTo{aToFrame}, RelativeTo{nearestCommonAncestor}); + if (downToDest.IsSingular()) { + return NONINVERTIBLE_TRANSFORM; + } + downToDest.Invert(); + aRect = TransformFrameRectToAncestor(aFromFrame, aRect, + RelativeTo{nearestCommonAncestor}); + + float devPixelsPerAppUnitFromFrame = + 1.0f / nearestCommonAncestor->PresContext()->AppUnitsPerDevPixel(); + float devPixelsPerAppUnitToFrame = + 1.0f / aToFrame->PresContext()->AppUnitsPerDevPixel(); + gfx::Rect toDevPixels = downToDest.ProjectRectBounds( + gfx::Rect(aRect.x * devPixelsPerAppUnitFromFrame, + aRect.y * devPixelsPerAppUnitFromFrame, + aRect.width * devPixelsPerAppUnitFromFrame, + aRect.height * devPixelsPerAppUnitFromFrame), + Rect(-std::numeric_limits<Float>::max() * devPixelsPerAppUnitFromFrame * + 0.5f, + -std::numeric_limits<Float>::max() * devPixelsPerAppUnitFromFrame * + 0.5f, + std::numeric_limits<Float>::max() * devPixelsPerAppUnitFromFrame, + std::numeric_limits<Float>::max() * devPixelsPerAppUnitFromFrame)); + aRect.x = NSToCoordRoundWithClamp(toDevPixels.x / devPixelsPerAppUnitToFrame); + aRect.y = NSToCoordRoundWithClamp(toDevPixels.y / devPixelsPerAppUnitToFrame); + aRect.width = + NSToCoordRoundWithClamp(toDevPixels.width / devPixelsPerAppUnitToFrame); + aRect.height = + NSToCoordRoundWithClamp(toDevPixels.height / devPixelsPerAppUnitToFrame); + return TRANSFORM_SUCCEEDED; +} + +nsRect nsLayoutUtils::GetRectRelativeToFrame(Element* aElement, + nsIFrame* aFrame) { + if (!aElement || !aFrame) { + return nsRect(); + } + + nsIFrame* frame = aElement->GetPrimaryFrame(); + if (!frame) { + return nsRect(); + } + + nsRect rect = frame->GetRectRelativeToSelf(); + nsLayoutUtils::TransformResult rv = + nsLayoutUtils::TransformRect(frame, aFrame, rect); + if (rv != nsLayoutUtils::TRANSFORM_SUCCEEDED) { + return nsRect(); + } + + return rect; +} + +bool nsLayoutUtils::ContainsPoint(const nsRect& aRect, const nsPoint& aPoint, + nscoord aInflateSize) { + nsRect rect = aRect; + rect.Inflate(aInflateSize); + return rect.Contains(aPoint); +} + +nsRect nsLayoutUtils::ClampRectToScrollFrames(nsIFrame* aFrame, + const nsRect& aRect) { + nsIFrame* closestScrollFrame = + nsLayoutUtils::GetClosestFrameOfType(aFrame, LayoutFrameType::Scroll); + + nsRect resultRect = aRect; + + while (closestScrollFrame) { + nsIScrollableFrame* sf = do_QueryFrame(closestScrollFrame); + + nsRect scrollPortRect = sf->GetScrollPortRect(); + nsLayoutUtils::TransformRect(closestScrollFrame, aFrame, scrollPortRect); + + resultRect = resultRect.Intersect(scrollPortRect); + + // Check whether aRect is visible in the scroll frame or not. + if (resultRect.IsEmpty()) { + break; + } + + // Get next ancestor scroll frame. + closestScrollFrame = nsLayoutUtils::GetClosestFrameOfType( + closestScrollFrame->GetParent(), LayoutFrameType::Scroll); + } + + return resultRect; +} + +bool nsLayoutUtils::GetLayerTransformForFrame(nsIFrame* aFrame, + Matrix4x4Flagged* aTransform) { + // FIXME/bug 796690: we can sometimes compute a transform in these + // cases, it just increases complexity considerably. Punt for now. + if (aFrame->Extend3DContext() || aFrame->GetTransformGetter()) { + return false; + } + + nsIFrame* root = nsLayoutUtils::GetDisplayRootFrame(aFrame); + if (root->HasAnyStateBits(NS_FRAME_UPDATE_LAYER_TREE)) { + // Content may have been invalidated, so we can't reliably compute + // the "layer transform" in general. + return false; + } + // If the caller doesn't care about the value, early-return to skip + // overhead below. + if (!aTransform) { + return true; + } + + nsDisplayListBuilder builder(root, + nsDisplayListBuilderMode::TransformComputation, + false /*don't build caret*/); + builder.BeginFrame(); + nsDisplayList list(&builder); + nsDisplayTransform* item = + MakeDisplayItem<nsDisplayTransform>(&builder, aFrame, &list, nsRect()); + MOZ_ASSERT(item); + + *aTransform = item->GetTransform(); + item->Destroy(&builder); + + builder.EndFrame(); + + return true; +} + +nsPoint nsLayoutUtils::TransformAncestorPointToFrame(RelativeTo aFrame, + const nsPoint& aPoint, + RelativeTo aAncestor) { + float factor = aFrame.mFrame->PresContext()->AppUnitsPerDevPixel(); + Point result(NSAppUnitsToFloatPixels(aPoint.x, factor), + NSAppUnitsToFloatPixels(aPoint.y, factor)); + + Maybe<Matrix4x4Flagged> matrixCache; + if (!TransformGfxPointFromAncestor(aFrame, result, aAncestor, matrixCache, + &result)) { + return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + } + + return nsPoint(NSFloatPixelsToAppUnits(float(result.x), factor), + NSFloatPixelsToAppUnits(float(result.y), factor)); +} + +nsRect nsLayoutUtils::TransformFrameRectToAncestor( + const nsIFrame* aFrame, const nsRect& aRect, RelativeTo aAncestor, + bool* aPreservesAxisAlignedRectangles /* = nullptr */, + Maybe<Matrix4x4Flagged>* aMatrixCache /* = nullptr */, + bool aStopAtStackingContextAndDisplayPortAndOOFFrame /* = false */, + nsIFrame** aOutAncestor /* = nullptr */) { + MOZ_ASSERT(IsAncestorFrameCrossDocInProcess(aAncestor.mFrame, aFrame), + "Fix the caller"); + float srcAppUnitsPerDevPixel = aFrame->PresContext()->AppUnitsPerDevPixel(); + Rect result(NSAppUnitsToFloatPixels(aRect.x, srcAppUnitsPerDevPixel), + NSAppUnitsToFloatPixels(aRect.y, srcAppUnitsPerDevPixel), + NSAppUnitsToFloatPixels(aRect.width, srcAppUnitsPerDevPixel), + NSAppUnitsToFloatPixels(aRect.height, srcAppUnitsPerDevPixel)); + result = TransformGfxRectToAncestor( + RelativeTo{aFrame}, result, aAncestor, aPreservesAxisAlignedRectangles, + aMatrixCache, aStopAtStackingContextAndDisplayPortAndOOFFrame, + aOutAncestor); + + float destAppUnitsPerDevPixel = + aAncestor.mFrame->PresContext()->AppUnitsPerDevPixel(); + return nsRect( + NSFloatPixelsToAppUnits(float(result.x), destAppUnitsPerDevPixel), + NSFloatPixelsToAppUnits(float(result.y), destAppUnitsPerDevPixel), + NSFloatPixelsToAppUnits(float(result.width), destAppUnitsPerDevPixel), + NSFloatPixelsToAppUnits(float(result.height), destAppUnitsPerDevPixel)); +} + +static LayoutDeviceIntPoint GetWidgetOffset(nsIWidget* aWidget, + nsIWidget*& aRootWidget) { + LayoutDeviceIntPoint offset(0, 0); + while (aWidget->WindowType() == eWindowType_child) { + nsIWidget* parent = aWidget->GetParent(); + if (!parent) { + break; + } + LayoutDeviceIntRect bounds = aWidget->GetBounds(); + offset += bounds.TopLeft(); + aWidget = parent; + } + aRootWidget = aWidget; + return offset; +} + +LayoutDeviceIntPoint nsLayoutUtils::WidgetToWidgetOffset(nsIWidget* aFrom, + nsIWidget* aTo) { + nsIWidget* fromRoot; + LayoutDeviceIntPoint fromOffset = GetWidgetOffset(aFrom, fromRoot); + nsIWidget* toRoot; + LayoutDeviceIntPoint toOffset = GetWidgetOffset(aTo, toRoot); + + if (fromRoot != toRoot) { + fromOffset = aFrom->WidgetToScreenOffset(); + toOffset = aTo->WidgetToScreenOffset(); + } + return fromOffset - toOffset; +} + +nsPoint nsLayoutUtils::TranslateWidgetToView(nsPresContext* aPresContext, + nsIWidget* aWidget, + const LayoutDeviceIntPoint& aPt, + nsView* aView) { + nsPoint viewOffset; + nsIWidget* viewWidget = aView->GetNearestWidget(&viewOffset); + if (!viewWidget) { + return nsPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + } + + LayoutDeviceIntPoint widgetPoint = + aPt + WidgetToWidgetOffset(aWidget, viewWidget); + nsPoint widgetAppUnits(aPresContext->DevPixelsToAppUnits(widgetPoint.x), + aPresContext->DevPixelsToAppUnits(widgetPoint.y)); + return widgetAppUnits - viewOffset; +} + +LayoutDeviceIntPoint nsLayoutUtils::TranslateViewToWidget( + nsPresContext* aPresContext, nsView* aView, nsPoint aPt, + ViewportType aViewportType, nsIWidget* aWidget) { + nsPoint viewOffset; + nsIWidget* viewWidget = aView->GetNearestWidget(&viewOffset); + if (!viewWidget) { + return LayoutDeviceIntPoint(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE); + } + + nsPoint pt = (aPt + viewOffset); + // The target coordinates are visual, so perform a layout-to-visual + // conversion if the incoming coordinates are layout. + if (aViewportType == ViewportType::Layout && aPresContext->GetPresShell()) { + pt = ViewportUtils::LayoutToVisual(pt, aPresContext->GetPresShell()); + } + LayoutDeviceIntPoint relativeToViewWidget( + aPresContext->AppUnitsToDevPixels(pt.x), + aPresContext->AppUnitsToDevPixels(pt.y)); + return relativeToViewWidget + WidgetToWidgetOffset(viewWidget, aWidget); +} + +StyleClear nsLayoutUtils::CombineClearType(StyleClear aOrigClearType, + StyleClear aNewClearType) { + StyleClear clearType = aOrigClearType; + switch (clearType) { + case StyleClear::Left: + if (StyleClear::Right == aNewClearType || + StyleClear::Both == aNewClearType) { + clearType = StyleClear::Both; + } + break; + case StyleClear::Right: + if (StyleClear::Left == aNewClearType || + StyleClear::Both == aNewClearType) { + clearType = StyleClear::Both; + } + break; + case StyleClear::None: + if (StyleClear::Left == aNewClearType || + StyleClear::Right == aNewClearType || + StyleClear::Both == aNewClearType) { + clearType = aNewClearType; + } + break; + case StyleClear::Both: + // Do nothing. + break; + } + return clearType; +} + +#ifdef MOZ_DUMP_PAINTING +# include <stdio.h> + +static bool gDumpEventList = false; + +// nsLayoutUtils::PaintFrame() can call itself recursively, so rather than +// maintaining a single paint count, we need a stack. +StaticAutoPtr<nsTArray<int>> gPaintCountStack; + +struct AutoNestedPaintCount { + AutoNestedPaintCount() { gPaintCountStack->AppendElement(0); } + ~AutoNestedPaintCount() { gPaintCountStack->RemoveLastElement(); } +}; + +#endif + +nsIFrame* nsLayoutUtils::GetFrameForPoint( + RelativeTo aRelativeTo, nsPoint aPt, const FrameForPointOptions& aOptions) { + AUTO_PROFILER_LABEL("nsLayoutUtils::GetFrameForPoint", LAYOUT); + + nsresult rv; + AutoTArray<nsIFrame*, 8> outFrames; + rv = GetFramesForArea(aRelativeTo, nsRect(aPt, nsSize(1, 1)), outFrames, + aOptions); + NS_ENSURE_SUCCESS(rv, nullptr); + return outFrames.Length() ? outFrames.ElementAt(0) : nullptr; +} + +nsresult nsLayoutUtils::GetFramesForArea(RelativeTo aRelativeTo, + const nsRect& aRect, + nsTArray<nsIFrame*>& aOutFrames, + const FrameForPointOptions& aOptions) { + AUTO_PROFILER_LABEL("nsLayoutUtils::GetFramesForArea", LAYOUT); + + nsIFrame* frame = const_cast<nsIFrame*>(aRelativeTo.mFrame); + + nsDisplayListBuilder builder(frame, nsDisplayListBuilderMode::EventDelivery, + false); + builder.BeginFrame(); + nsDisplayList list(&builder); + + if (aOptions.mBits.contains(FrameForPointOption::IgnorePaintSuppression)) { + builder.IgnorePaintSuppression(); + } + if (aOptions.mBits.contains(FrameForPointOption::IgnoreRootScrollFrame)) { + nsIFrame* rootScrollFrame = frame->PresShell()->GetRootScrollFrame(); + if (rootScrollFrame) { + builder.SetIgnoreScrollFrame(rootScrollFrame); + } + } + if (aRelativeTo.mViewportType == ViewportType::Layout) { + builder.SetIsRelativeToLayoutViewport(); + } + if (aOptions.mBits.contains(FrameForPointOption::IgnoreCrossDoc)) { + builder.SetDescendIntoSubdocuments(false); + } + + if (aOptions.mBits.contains(FrameForPointOption::OnlyVisible)) { + builder.SetHitTestIsForVisibility(aOptions.mVisibleThreshold); + } + + builder.EnterPresShell(frame); + + builder.SetVisibleRect(aRect); + builder.SetDirtyRect(aRect); + + frame->BuildDisplayListForStackingContext(&builder, &list); + builder.LeavePresShell(frame, nullptr); + +#ifdef MOZ_DUMP_PAINTING + if (gDumpEventList) { + fprintf_stderr(stderr, "Event handling --- (%d,%d):\n", aRect.x, aRect.y); + + std::stringstream ss; + nsIFrame::PrintDisplayList(&builder, list, ss); + print_stderr(ss); + } +#endif + + nsDisplayItem::HitTestState hitTestState; + list.HitTest(&builder, aRect, &hitTestState, &aOutFrames); + list.DeleteAll(&builder); + builder.EndFrame(); + return NS_OK; +} + +mozilla::ParentLayerToScreenScale2D +nsLayoutUtils::GetTransformToAncestorScaleCrossProcessForFrameMetrics( + const nsIFrame* aFrame) { + ParentLayerToScreenScale2D transformToAncestorScale = + ViewAs<ParentLayerToScreenScale2D>( + nsLayoutUtils::GetTransformToAncestorScale(aFrame)); + + if (BrowserChild* browserChild = BrowserChild::GetFrom(aFrame->PresShell())) { + transformToAncestorScale = + ViewTargetAs<ParentLayerPixel>( + transformToAncestorScale, + PixelCastJustification::PropagatingToChildProcess) * + browserChild->GetEffectsInfo().mTransformToAncestorScale; + } + + return transformToAncestorScale; +} + +// aScrollFrameAsScrollable must be non-nullptr and queryable to an nsIFrame +FrameMetrics nsLayoutUtils::CalculateBasicFrameMetrics( + nsIScrollableFrame* aScrollFrame) { + nsIFrame* frame = do_QueryFrame(aScrollFrame); + MOZ_ASSERT(frame); + + // Calculate the metrics necessary for calculating the displayport. + // This code has a lot in common with the code in ComputeFrameMetrics(); + // we may want to refactor this at some point. + FrameMetrics metrics; + nsPresContext* presContext = frame->PresContext(); + PresShell* presShell = presContext->PresShell(); + CSSToLayoutDeviceScale deviceScale = presContext->CSSToDevPixelScale(); + float resolution = 1.0f; + bool isRcdRsf = aScrollFrame->IsRootScrollFrameOfDocument() && + presContext->IsRootContentDocumentCrossProcess(); + metrics.SetIsRootContent(isRcdRsf); + if (isRcdRsf) { + // Only the root content document's root scrollable frame should pick up + // the presShell's resolution. All the other frames are 1.0. + resolution = presShell->GetResolution(); + } + LayoutDeviceToLayerScale cumulativeResolution( + LayoutDeviceToLayerScale(presShell->GetCumulativeResolution())); + + LayerToParentLayerScale layerToParentLayerScale(1.0f); + metrics.SetDevPixelsPerCSSPixel(deviceScale); + metrics.SetPresShellResolution(resolution); + + metrics.SetTransformToAncestorScale( + GetTransformToAncestorScaleCrossProcessForFrameMetrics(frame)); + metrics.SetCumulativeResolution(cumulativeResolution); + metrics.SetZoom(deviceScale * cumulativeResolution * layerToParentLayerScale); + + // Only the size of the composition bounds is relevant to the + // displayport calculation, not its origin. + nsSize compositionSize = + nsLayoutUtils::CalculateCompositionSizeForFrame(frame); + LayoutDeviceToParentLayerScale compBoundsScale; + if (frame == presShell->GetRootScrollFrame() && + presContext->IsRootContentDocumentCrossProcess()) { + if (presContext->GetParentPresContext()) { + float res = presContext->GetParentPresContext() + ->PresShell() + ->GetCumulativeResolution(); + compBoundsScale = LayoutDeviceToParentLayerScale(res); + } + } else { + compBoundsScale = cumulativeResolution * layerToParentLayerScale; + } + metrics.SetCompositionBounds( + LayoutDeviceRect::FromAppUnits(nsRect(nsPoint(0, 0), compositionSize), + presContext->AppUnitsPerDevPixel()) * + compBoundsScale); + + metrics.SetBoundingCompositionSize( + nsLayoutUtils::CalculateBoundingCompositionSize(frame, false, metrics)); + + metrics.SetLayoutViewport( + CSSRect::FromAppUnits(nsRect(aScrollFrame->GetScrollPosition(), + aScrollFrame->GetScrollPortRect().Size()))); + metrics.SetVisualScrollOffset( + isRcdRsf ? CSSPoint::FromAppUnits(presShell->GetVisualViewportOffset()) + : metrics.GetLayoutViewport().TopLeft()); + + metrics.SetScrollableRect(CSSRect::FromAppUnits( + nsLayoutUtils::CalculateScrollableRectForFrame(aScrollFrame, nullptr))); + + return metrics; +} + +nsIScrollableFrame* nsLayoutUtils::GetAsyncScrollableAncestorFrame( + nsIFrame* aTarget) { + uint32_t flags = nsLayoutUtils::SCROLLABLE_ALWAYS_MATCH_ROOT | + nsLayoutUtils::SCROLLABLE_ONLY_ASYNC_SCROLLABLE | + nsLayoutUtils::SCROLLABLE_FIXEDPOS_FINDS_ROOT; + return nsLayoutUtils::GetNearestScrollableFrame(aTarget, flags); +} + +void nsLayoutUtils::AddExtraBackgroundItems(nsDisplayListBuilder* aBuilder, + nsDisplayList* aList, + nsIFrame* aFrame, + const nsRect& aCanvasArea, + const nsRegion& aVisibleRegion, + nscolor aBackstop) { + LayoutFrameType frameType = aFrame->Type(); + nsPresContext* presContext = aFrame->PresContext(); + PresShell* presShell = presContext->PresShell(); + + // For the viewport frame in print preview/page layout we want to paint + // the grey background behind the page, not the canvas color. + if (frameType == LayoutFrameType::Viewport && + nsLayoutUtils::NeedsPrintPreviewBackground(presContext)) { + nsRect bounds = + nsRect(aBuilder->ToReferenceFrame(aFrame), aFrame->GetSize()); + nsDisplayListBuilder::AutoBuildingDisplayList buildingDisplayList( + aBuilder, aFrame, bounds, bounds); + presShell->AddPrintPreviewBackgroundItem(aBuilder, aList, aFrame, bounds); + } else if (frameType != LayoutFrameType::Page) { + // For printing, this function is first called on an nsPageFrame, which + // creates a display list with a PageContent item. The PageContent item's + // paint function calls this function on the nsPageFrame's child which is + // an nsPageContentFrame. We only want to add the canvas background color + // item once, for the nsPageContentFrame. + + // Add the canvas background color to the bottom of the list. This + // happens after we've built the list so that AddCanvasBackgroundColorItem + // can monkey with the contents if necessary. + nsRect canvasArea = aVisibleRegion.GetBounds(); + canvasArea.IntersectRect(aCanvasArea, canvasArea); + nsDisplayListBuilder::AutoBuildingDisplayList buildingDisplayList( + aBuilder, aFrame, canvasArea, canvasArea); + presShell->AddCanvasBackgroundColorItem(aBuilder, aList, aFrame, canvasArea, + aBackstop); + } +} + +// #define PRINT_HITTESTINFO_STATS +#ifdef PRINT_HITTESTINFO_STATS +void PrintHitTestInfoStatsInternal(nsDisplayList* aList, int& aTotal, + int& aHitTest, int& aVisible, + int& aSpecial) { + for (nsDisplayItem* i : *aList) { + aTotal++; + + if (i->GetChildren()) { + PrintHitTestInfoStatsInternal(i->GetChildren(), aTotal, aHitTest, + aVisible, aSpecial); + } + + if (i->GetType() == DisplayItemType::TYPE_COMPOSITOR_HITTEST_INFO) { + aHitTest++; + + const auto& hitTestInfo = static_cast<nsDisplayCompositorHitTestInfo*>(i) + ->GetHitTestInfo() + .Info(); + + if (hitTestInfo.size() > 1) { + aSpecial++; + continue; + } + + if (hitTestInfo == CompositorHitTestFlags::eVisibleToHitTest) { + aVisible++; + continue; + } + + aSpecial++; + } + } +} + +void PrintHitTestInfoStats(nsDisplayList* aList) { + int total = 0; + int hitTest = 0; + int visible = 0; + int special = 0; + + PrintHitTestInfoStatsInternal(aList, total, hitTest, visible, special); + + double ratio = (double)hitTest / (double)total; + + printf( + "List %p: total items: %d, hit test items: %d, ratio: %f, visible: %d, " + "special: %d\n", + aList, total, hitTest, ratio, visible, special); +} +#endif + +// Apply a batch of effects updates generated during a paint to their +// respective remote browsers. +static void ApplyEffectsUpdates( + const nsTHashMap<nsPtrHashKey<RemoteBrowser>, EffectsInfo>& aUpdates) { + for (const auto& entry : aUpdates) { + auto* browser = entry.GetKey(); + const auto& update = entry.GetData(); + browser->UpdateEffects(update); + } +} + +static void DumpBeforePaintDisplayList(UniquePtr<std::stringstream>& aStream, + nsDisplayListBuilder* aBuilder, + nsDisplayList* aList, + const nsRect& aVisibleRect) { +#ifdef MOZ_DUMP_PAINTING + if (gfxEnv::MOZ_DUMP_PAINT_TO_FILE()) { + nsCString string("dump-"); + // Include the process ID in the dump file name, to make sure that in an + // e10s setup different processes don't clobber each other's dump files. + string.AppendInt(getpid()); + for (int paintCount : *gPaintCountStack) { + string.AppendLiteral("-"); + string.AppendInt(paintCount); + } + string.AppendLiteral(".html"); + gfxUtils::sDumpPaintFile = fopen(string.BeginReading(), "w"); + } else { + gfxUtils::sDumpPaintFile = stderr; + } + if (gfxEnv::MOZ_DUMP_PAINT_TO_FILE()) { + *aStream << "<html><head><script>\n" + "var array = {};\n" + "function ViewImage(index) { \n" + " var image = document.getElementById(index);\n" + " if (image.src) {\n" + " image.removeAttribute('src');\n" + " } else {\n" + " image.src = array[index];\n" + " }\n" + "}</script></head><body>"; + } +#endif + *aStream << nsPrintfCString( + "Painting --- before optimization (dirty %d,%d,%d,%d):\n", + aVisibleRect.x, aVisibleRect.y, aVisibleRect.width, + aVisibleRect.height) + .get(); + nsIFrame::PrintDisplayList(aBuilder, *aList, *aStream, + gfxEnv::MOZ_DUMP_PAINT_TO_FILE()); + + if (gfxEnv::MOZ_DUMP_PAINT() || gfxEnv::MOZ_DUMP_PAINT_ITEMS()) { + // Flush stream now to avoid reordering dump output relative to + // messages dumped by PaintRoot below. + fprint_stderr(gfxUtils::sDumpPaintFile, *aStream); + aStream = MakeUnique<std::stringstream>(); + } +} + +static void DumpAfterPaintDisplayList(UniquePtr<std::stringstream>& aStream, + nsDisplayListBuilder* aBuilder, + nsDisplayList* aList) { + *aStream << "Painting --- after optimization:\n"; + nsIFrame::PrintDisplayList(aBuilder, *aList, *aStream, + gfxEnv::MOZ_DUMP_PAINT_TO_FILE()); + + fprint_stderr(gfxUtils::sDumpPaintFile, *aStream); + +#ifdef MOZ_DUMP_PAINTING + if (gfxEnv::MOZ_DUMP_PAINT_TO_FILE()) { + *aStream << "</body></html>"; + } + if (gfxEnv::MOZ_DUMP_PAINT_TO_FILE()) { + fclose(gfxUtils::sDumpPaintFile); + } +#endif + + std::stringstream lsStream; + nsIFrame::PrintDisplayList(aBuilder, *aList, lsStream); +} + +struct TemporaryDisplayListBuilder { + TemporaryDisplayListBuilder(nsIFrame* aFrame, + nsDisplayListBuilderMode aBuilderMode, + const bool aBuildCaret) + : mBuilder(aFrame, aBuilderMode, aBuildCaret), mList(&mBuilder) {} + + ~TemporaryDisplayListBuilder() { mList.DeleteAll(&mBuilder); } + + nsDisplayListBuilder mBuilder; + nsDisplayList mList; + RetainedDisplayListMetrics mMetrics; +}; + +void nsLayoutUtils::PaintFrame(gfxContext* aRenderingContext, nsIFrame* aFrame, + const nsRegion& aDirtyRegion, nscolor aBackstop, + nsDisplayListBuilderMode aBuilderMode, + PaintFrameFlags aFlags) { + AUTO_PROFILER_LABEL("nsLayoutUtils::PaintFrame", GRAPHICS); + +#ifdef MOZ_DUMP_PAINTING + if (!gPaintCountStack) { + gPaintCountStack = new nsTArray<int>(); + ClearOnShutdown(&gPaintCountStack); + + gPaintCountStack->AppendElement(0); + } + ++gPaintCountStack->LastElement(); + AutoNestedPaintCount nestedPaintCount; +#endif + + nsIFrame* displayRoot = GetDisplayRootFrame(aFrame); + + if (aFlags & PaintFrameFlags::WidgetLayers) { + nsView* view = aFrame->GetView(); + if (!(view && view->GetWidget() && displayRoot == aFrame)) { + aFlags &= ~PaintFrameFlags::WidgetLayers; + NS_ASSERTION(aRenderingContext, "need a rendering context"); + } + } + + nsPresContext* presContext = aFrame->PresContext(); + PresShell* presShell = presContext->PresShell(); + + TimeStamp startBuildDisplayList = TimeStamp::Now(); + auto dlTimerId = mozilla::glean::paint::build_displaylist_time.Start(); + + const bool buildCaret = !(aFlags & PaintFrameFlags::HideCaret); + + // Note that isForPainting here does not include the PaintForPrinting builder + // mode; that's OK because there is no point in using retained display lists + // for a print destination. + const bool isForPainting = (aFlags & PaintFrameFlags::WidgetLayers) && + aBuilderMode == nsDisplayListBuilderMode::Painting; + + // Only allow retaining for painting when preffed on, and for root frames + // (since the modified frame tracking is per-root-frame). + const bool retainDisplayList = + isForPainting && AreRetainedDisplayListsEnabled() && !aFrame->GetParent(); + + RetainedDisplayListBuilder* retainedBuilder = nullptr; + Maybe<TemporaryDisplayListBuilder> temporaryBuilder; + + nsDisplayListBuilder* builder = nullptr; + nsDisplayList* list = nullptr; + RetainedDisplayListMetrics* metrics = nullptr; + + if (retainDisplayList) { + MOZ_ASSERT(aFrame == displayRoot); + retainedBuilder = aFrame->GetProperty(RetainedDisplayListBuilder::Cached()); + if (!retainedBuilder) { + retainedBuilder = + new RetainedDisplayListBuilder(aFrame, aBuilderMode, buildCaret); + aFrame->SetProperty(RetainedDisplayListBuilder::Cached(), + retainedBuilder); + } + + builder = retainedBuilder->Builder(); + list = retainedBuilder->List(); + metrics = retainedBuilder->Metrics(); + } else { + temporaryBuilder.emplace(aFrame, aBuilderMode, buildCaret); + builder = &temporaryBuilder->mBuilder; + list = &temporaryBuilder->mList; + metrics = &temporaryBuilder->mMetrics; + } + + MOZ_ASSERT(builder && list && metrics); + + nsAutoString uri; + Document* doc = presContext->Document(); + MOZ_ASSERT(doc); + Unused << doc->GetDocumentURI(uri); + + nsAutoString frameName, displayRootName; +#ifdef DEBUG_FRAME_DUMP + aFrame->GetFrameName(frameName); + displayRoot->GetFrameName(displayRootName); +#endif + + DL_LOGI("PaintFrame: %p (%s), DisplayRoot: %p (%s), Builder: %p, URI: %s", + aFrame, NS_ConvertUTF16toUTF8(frameName).get(), displayRoot, + NS_ConvertUTF16toUTF8(displayRootName).get(), retainedBuilder, + NS_ConvertUTF16toUTF8(uri).get()); + + metrics->Reset(); + metrics->StartBuild(); + + builder->BeginFrame(); + + if (aFlags & PaintFrameFlags::InTransform) { + builder->SetInTransform(true); + } + if (aFlags & PaintFrameFlags::SyncDecodeImages) { + builder->SetSyncDecodeImages(true); + } + if (aFlags & (PaintFrameFlags::WidgetLayers | PaintFrameFlags::ToWindow)) { + builder->SetPaintingToWindow(true); + } + if (aFlags & PaintFrameFlags::UseHighQualityScaling) { + builder->SetUseHighQualityScaling(true); + } + if (aFlags & PaintFrameFlags::ForWebRender) { + builder->SetPaintingForWebRender(true); + } + if (aFlags & PaintFrameFlags::IgnoreSuppression) { + builder->IgnorePaintSuppression(); + } + + if (BrowsingContext* bc = presContext->Document()->GetBrowsingContext()) { + builder->SetInActiveDocShell(bc->IsActive()); + } + + nsRect rootInkOverflow = aFrame->InkOverflowRectRelativeToSelf(); + + // If the dynamic toolbar is completely collapsed, the visible rect should + // be expanded to include this area. + if (presContext->IsRootContentDocumentCrossProcess() && + presContext->HasDynamicToolbar()) { + rootInkOverflow.SizeTo(nsLayoutUtils::ExpandHeightForDynamicToolbar( + presContext, rootInkOverflow.Size())); + } + + // If we are in a remote browser, then apply clipping from ancestor browsers + if (BrowserChild* browserChild = BrowserChild::GetFrom(presShell)) { + if (!browserChild->IsTopLevel()) { + Maybe<nsRect> unscaledVisibleRect = browserChild->GetVisibleRect(); + + if (!unscaledVisibleRect) { + unscaledVisibleRect = Some(nsRect()); + } + + rootInkOverflow.IntersectRect(rootInkOverflow, *unscaledVisibleRect); + } + } + + builder->ClearHaveScrollableDisplayPort(); + if (builder->IsPaintingToWindow()) { + DisplayPortUtils::MaybeCreateDisplayPortInFirstScrollFrameEncountered( + aFrame, builder); + } + + nsIFrame* rootScrollFrame = presShell->GetRootScrollFrame(); + if (rootScrollFrame && !aFrame->GetParent()) { + nsIScrollableFrame* rootScrollableFrame = + presShell->GetRootScrollFrameAsScrollable(); + MOZ_ASSERT(rootScrollableFrame); + nsRect displayPortBase = rootInkOverflow; + nsRect temp = displayPortBase; + Unused << rootScrollableFrame->DecideScrollableLayer( + builder, &displayPortBase, &temp, + /* aSetBase = */ true); + } + + nsRegion visibleRegion; + if (aFlags & PaintFrameFlags::WidgetLayers) { + // This layer tree will be reused, so we'll need to calculate it + // for the whole "visible" area of the window + // + // |ignoreViewportScrolling| and |usingDisplayPort| are persistent + // document-rendering state. We rely on PresShell to flush + // retained layers as needed when that persistent state changes. + visibleRegion = rootInkOverflow; + } else { + visibleRegion = aDirtyRegion; + } + + Maybe<nsPoint> originalScrollPosition; + auto maybeResetScrollPosition = MakeScopeExit([&]() { + if (originalScrollPosition && rootScrollFrame) { + nsIScrollableFrame* rootScrollableFrame = + presShell->GetRootScrollFrameAsScrollable(); + MOZ_ASSERT(rootScrollableFrame->GetScrolledFrame()->GetPosition() == + nsPoint()); + rootScrollableFrame->GetScrolledFrame()->SetPosition( + *originalScrollPosition); + } + }); + + nsRect canvasArea(nsPoint(0, 0), aFrame->GetSize()); + bool ignoreViewportScrolling = + !aFrame->GetParent() && presShell->IgnoringViewportScrolling(); + if (ignoreViewportScrolling && rootScrollFrame) { + nsIScrollableFrame* rootScrollableFrame = + presShell->GetRootScrollFrameAsScrollable(); + if (aFlags & PaintFrameFlags::ResetViewportScrolling) { + // Temporarily scroll the root scroll frame to 0,0 so that position:fixed + // elements will appear fixed to the top-left of the document. We manually + // set the position of the scrolled frame instead of using ScrollTo, since + // the latter fires scroll listeners, which we don't want. + originalScrollPosition.emplace( + rootScrollableFrame->GetScrolledFrame()->GetPosition()); + rootScrollableFrame->GetScrolledFrame()->SetPosition(nsPoint()); + } + if (aFlags & PaintFrameFlags::DocumentRelative) { + // Make visibleRegion and aRenderingContext relative to the + // scrolled frame instead of the root frame. + nsPoint pos = rootScrollableFrame->GetScrollPosition(); + visibleRegion.MoveBy(-pos); + if (aRenderingContext) { + gfxPoint devPixelOffset = nsLayoutUtils::PointToGfxPoint( + pos, presContext->AppUnitsPerDevPixel()); + aRenderingContext->SetMatrixDouble( + aRenderingContext->CurrentMatrixDouble().PreTranslate( + devPixelOffset)); + } + } + builder->SetIgnoreScrollFrame(rootScrollFrame); + + nsCanvasFrame* canvasFrame = + do_QueryFrame(rootScrollableFrame->GetScrolledFrame()); + if (canvasFrame) { + // Use UnionRect here to ensure that areas where the scrollbars + // were are still filled with the background color. + canvasArea.UnionRect( + canvasArea, + canvasFrame->CanvasArea() + builder->ToReferenceFrame(canvasFrame)); + } + } + + nsRect visibleRect = visibleRegion.GetBounds(); + PartialUpdateResult updateState = PartialUpdateResult::Failed; + + { + AUTO_PROFILER_LABEL_CATEGORY_PAIR(GRAPHICS_DisplayListBuilding); + AUTO_PROFILER_TRACING_MARKER("Paint", "DisplayList", GRAPHICS); + PerfStats::AutoMetricRecording<PerfStats::Metric::DisplayListBuilding> + autoRecording; + + ViewID id = ScrollableLayerGuid::NULL_SCROLL_ID; + nsDisplayListBuilder::AutoCurrentActiveScrolledRootSetter asrSetter( + builder); + + if (presShell->GetDocument() && + presShell->GetDocument()->IsRootDisplayDocument() && + !presShell->GetRootScrollFrame()) { + // In cases where the root document is a XUL document, we want to take + // the ViewID from the root element, as that will be the ViewID of the + // root APZC in the tree. Skip doing this in cases where we know + // nsGfxScrollFrame::BuilDisplayList will do it instead. + if (dom::Element* element = + presShell->GetDocument()->GetDocumentElement()) { + id = nsLayoutUtils::FindOrCreateIDFor(element); + } + // In some cases we get a root document here on an APZ-enabled window + // that doesn't have the root displayport initialized yet, even though + // the ChromeProcessController is supposed to do it when the widget is + // created. This can happen simply because the ChromeProcessController + // does it on the next spin of the event loop, and we can trigger a + // paint synchronously after window creation but before that runs. In + // that case we should initialize the root displayport here before we do + // the paint. + } else if (XRE_IsParentProcess() && presContext->IsRoot() && + presShell->GetDocument() != nullptr && + presShell->GetRootScrollFrame() != nullptr && + nsLayoutUtils::UsesAsyncScrolling( + presShell->GetRootScrollFrame())) { + if (dom::Element* element = + presShell->GetDocument()->GetDocumentElement()) { + if (!DisplayPortUtils::HasNonMinimalDisplayPort(element)) { + APZCCallbackHelper::InitializeRootDisplayport(presShell); + } + } + } + + asrSetter.SetCurrentScrollParentId(id); + + builder->SetVisibleRect(visibleRect); + builder->SetIsBuilding(true); + builder->SetAncestorHasApzAwareEventHandler( + gfxPlatform::AsyncPanZoomEnabled() && + nsLayoutUtils::HasDocumentLevelListenersForApzAwareEvents(presShell)); + + // If a pref is toggled that adds or removes display list items, + // we need to rebuild the display list. The pref may be toggled + // manually by the user, or during test setup. + if (retainDisplayList && + !builder->ShouldRebuildDisplayListDueToPrefChange()) { + // Attempt to do a partial build and merge into the existing list. + // This calls BuildDisplayListForStacking context on a subset of the + // viewport. + updateState = retainedBuilder->AttemptPartialUpdate(aBackstop); + metrics->EndPartialBuild(updateState); + } else { + // Partial updates are disabled. + DL_LOGI("Partial updates are disabled"); + metrics->mPartialUpdateResult = PartialUpdateResult::Failed; + metrics->mPartialUpdateFailReason = PartialUpdateFailReason::Disabled; + } + + // Rebuild the full display list if the partial display list build failed. + bool doFullRebuild = updateState == PartialUpdateResult::Failed; + + if (StaticPrefs::layout_display_list_build_twice()) { + // Build display list twice to compare partial and full display list + // build times. + metrics->StartBuild(); + doFullRebuild = true; + } + + if (doFullRebuild) { + if (retainDisplayList) { + retainedBuilder->ClearRetainedData(); +#ifdef DEBUG + mozilla::RDLUtils::AssertFrameSubtreeUnmodified( + builder->RootReferenceFrame()); +#endif + } + + list->DeleteAll(builder); + + builder->ClearRetainedWindowRegions(); + builder->ClearWillChangeBudgets(); + + builder->EnterPresShell(aFrame); + builder->SetDirtyRect(visibleRect); + + DL_LOGI("Starting full display list build, root frame: %p", + builder->RootReferenceFrame()); + + aFrame->BuildDisplayListForStackingContext(builder, list); + AddExtraBackgroundItems(builder, list, aFrame, canvasArea, visibleRegion, + aBackstop); + + builder->LeavePresShell(aFrame, list); + metrics->EndFullBuild(); + + DL_LOGI("Finished full display list build"); + updateState = PartialUpdateResult::Updated; + } + + builder->SetIsBuilding(false); + builder->IncrementPresShellPaintCount(presShell); + } + + MOZ_ASSERT(updateState != PartialUpdateResult::Failed); + builder->Check(); + + const double geckoDLBuildTime = + (TimeStamp::Now() - startBuildDisplayList).ToMilliseconds(); + mozilla::glean::paint::build_displaylist_time.StopAndAccumulate( + std::move(dlTimerId)); + + bool consoleNeedsDisplayList = + (gfxUtils::DumpDisplayList() || gfxEnv::MOZ_DUMP_PAINT()) && + builder->IsInActiveDocShell(); +#ifdef MOZ_DUMP_PAINTING + FILE* savedDumpFile = gfxUtils::sDumpPaintFile; +#endif + + UniquePtr<std::stringstream> ss; + if (consoleNeedsDisplayList) { + ss = MakeUnique<std::stringstream>(); + *ss << "Display list for " << uri << "\n"; + DumpBeforePaintDisplayList(ss, builder, list, visibleRect); + } + + uint32_t flags = nsDisplayList::PAINT_DEFAULT; + if (aFlags & PaintFrameFlags::WidgetLayers) { + flags |= nsDisplayList::PAINT_USE_WIDGET_LAYERS; + if (!(aFlags & PaintFrameFlags::DocumentRelative)) { + nsIWidget* widget = aFrame->GetNearestWidget(); + if (widget) { + // If we're finished building display list items for painting of the + // outermost pres shell, notify the widget about any toolbars we've + // encountered. + widget->UpdateThemeGeometries(builder->GetThemeGeometries()); + } + } + } + if (aFlags & PaintFrameFlags::ExistingTransaction) { + flags |= nsDisplayList::PAINT_EXISTING_TRANSACTION; + } + if (updateState == PartialUpdateResult::NoChange && !aRenderingContext) { + flags |= nsDisplayList::PAINT_IDENTICAL_DISPLAY_LIST; + } + +#ifdef PRINT_HITTESTINFO_STATS + if (XRE_IsContentProcess()) { + PrintHitTestInfoStats(list); + } +#endif + + TimeStamp paintStart = TimeStamp::Now(); + list->PaintRoot(builder, aRenderingContext, flags, Some(geckoDLBuildTime)); + Telemetry::AccumulateTimeDelta(Telemetry::PAINT_RASTERIZE_TIME, paintStart); + + if (builder->IsPaintingToWindow()) { + presShell->EndPaint(); + } + builder->Check(); + + if (consoleNeedsDisplayList) { + DumpAfterPaintDisplayList(ss, builder, list); + } + +#ifdef MOZ_DUMP_PAINTING + gfxUtils::sDumpPaintFile = savedDumpFile; +#endif + + // Update the widget's opaque region information. This sets + // glass boundaries on Windows. Also set up the window dragging region. + if ((aFlags & PaintFrameFlags::WidgetLayers) && + !(aFlags & PaintFrameFlags::DocumentRelative)) { + nsIWidget* widget = aFrame->GetNearestWidget(); + if (widget) { + nsRegion opaqueRegion; + opaqueRegion.And(builder->GetWindowExcludeGlassRegion(), + builder->GetWindowOpaqueRegion()); + widget->UpdateOpaqueRegion(LayoutDeviceIntRegion::FromUnknownRegion( + opaqueRegion.ToNearestPixels(presContext->AppUnitsPerDevPixel()))); + + widget->UpdateWindowDraggingRegion(builder->GetWindowDraggingRegion()); + } + } + + // Apply effects updates if we were actually painting + if (isForPainting) { + ApplyEffectsUpdates(builder->GetEffectUpdates()); + } + + builder->Check(); + + { + AUTO_PROFILER_TRACING_MARKER("Paint", "DisplayListResources", GRAPHICS); + + builder->EndFrame(); + + if (temporaryBuilder) { + temporaryBuilder.reset(); + } + } + +#if 0 + if (XRE_IsParentProcess()) { + if (metrics->mPartialUpdateResult == PartialUpdateResult::Failed) { + printf("DL partial update failed: %s, Frame: %p\n", + metrics->FailReasonString(), aFrame); + } else { + printf( + "DL partial build success!" + " new: %d, reused: %d, rebuilt: %d, removed: %d, total: %d\n", + metrics->mNewItems, metrics->mReusedItems, metrics->mRebuiltItems, + metrics->mRemovedItems, metrics->mTotalItems); + } + } +#endif +} + +/** + * Uses a binary search for find where the cursor falls in the line of text + * It also keeps track of the part of the string that has already been measured + * so it doesn't have to keep measuring the same text over and over + * + * @param "aBaseWidth" contains the width in twips of the portion + * of the text that has already been measured, and aBaseInx contains + * the index of the text that has already been measured. + * + * @param aTextWidth returns the (in twips) the length of the text that falls + * before the cursor aIndex contains the index of the text where the cursor + * falls + */ +bool nsLayoutUtils::BinarySearchForPosition( + DrawTarget* aDrawTarget, nsFontMetrics& aFontMetrics, const char16_t* aText, + int32_t aBaseWidth, int32_t aBaseInx, int32_t aStartInx, int32_t aEndInx, + int32_t aCursorPos, int32_t& aIndex, int32_t& aTextWidth) { + int32_t range = aEndInx - aStartInx; + if ((range == 1) || (range == 2 && NS_IS_HIGH_SURROGATE(aText[aStartInx]))) { + aIndex = aStartInx + aBaseInx; + aTextWidth = nsLayoutUtils::AppUnitWidthOfString(aText, aIndex, + aFontMetrics, aDrawTarget); + return true; + } + + int32_t inx = aStartInx + (range / 2); + + // Make sure we don't leave a dangling low surrogate + if (NS_IS_HIGH_SURROGATE(aText[inx - 1])) inx++; + + int32_t textWidth = nsLayoutUtils::AppUnitWidthOfString( + aText, inx, aFontMetrics, aDrawTarget); + + int32_t fullWidth = aBaseWidth + textWidth; + if (fullWidth == aCursorPos) { + aTextWidth = textWidth; + aIndex = inx; + return true; + } else if (aCursorPos < fullWidth) { + aTextWidth = aBaseWidth; + if (BinarySearchForPosition(aDrawTarget, aFontMetrics, aText, aBaseWidth, + aBaseInx, aStartInx, inx, aCursorPos, aIndex, + aTextWidth)) { + return true; + } + } else { + aTextWidth = fullWidth; + if (BinarySearchForPosition(aDrawTarget, aFontMetrics, aText, aBaseWidth, + aBaseInx, inx, aEndInx, aCursorPos, aIndex, + aTextWidth)) { + return true; + } + } + return false; +} + +void nsLayoutUtils::AddBoxesForFrame(nsIFrame* aFrame, + nsLayoutUtils::BoxCallback* aCallback) { + auto pseudoType = aFrame->Style()->GetPseudoType(); + + if (pseudoType == PseudoStyleType::tableWrapper) { + AddBoxesForFrame(aFrame->PrincipalChildList().FirstChild(), aCallback); + if (aCallback->mIncludeCaptionBoxForTable) { + nsIFrame* kid = + aFrame->GetChildList(FrameChildListID::Caption).FirstChild(); + if (kid) { + AddBoxesForFrame(kid, aCallback); + } + } + } else if (pseudoType == PseudoStyleType::mozBlockInsideInlineWrapper || + pseudoType == PseudoStyleType::mozMathMLAnonymousBlock) { + for (nsIFrame* kid : aFrame->PrincipalChildList()) { + AddBoxesForFrame(kid, aCallback); + } + } else { + aCallback->AddBox(aFrame); + } +} + +void nsLayoutUtils::GetAllInFlowBoxes(nsIFrame* aFrame, + BoxCallback* aCallback) { + aCallback->mInTargetContinuation = false; + while (aFrame) { + AddBoxesForFrame(aFrame, aCallback); + aFrame = nsLayoutUtils::GetNextContinuationOrIBSplitSibling(aFrame); + aCallback->mInTargetContinuation = true; + } +} + +nsIFrame* nsLayoutUtils::GetFirstNonAnonymousFrame(nsIFrame* aFrame) { + while (aFrame) { + auto pseudoType = aFrame->Style()->GetPseudoType(); + + if (pseudoType == PseudoStyleType::tableWrapper) { + nsIFrame* f = + GetFirstNonAnonymousFrame(aFrame->PrincipalChildList().FirstChild()); + if (f) { + return f; + } + nsIFrame* kid = + aFrame->GetChildList(FrameChildListID::Caption).FirstChild(); + if (kid) { + f = GetFirstNonAnonymousFrame(kid); + if (f) { + return f; + } + } + } else if (pseudoType == PseudoStyleType::mozBlockInsideInlineWrapper || + pseudoType == PseudoStyleType::mozMathMLAnonymousBlock) { + for (nsIFrame* kid : aFrame->PrincipalChildList()) { + nsIFrame* f = GetFirstNonAnonymousFrame(kid); + if (f) { + return f; + } + } + } else { + return aFrame; + } + + aFrame = nsLayoutUtils::GetNextContinuationOrIBSplitSibling(aFrame); + } + return nullptr; +} + +struct BoxToRect : public nsLayoutUtils::BoxCallback { + const nsIFrame* mRelativeTo; + RectCallback* mCallback; + uint32_t mFlags; + // If the frame we're measuring relative to is the root, we know all frames + // are descendants of it, so we don't need to compute the common ancestor + // between a frame and mRelativeTo. + bool mRelativeToIsRoot; + // For the same reason, if the frame we're measuring relative to is the target + // (this is useful for IntersectionObserver), we know all frames are + // descendants of it except if we're in a continuation or ib-split-sibling of + // it. + bool mRelativeToIsTarget; + + BoxToRect(const nsIFrame* aTargetFrame, const nsIFrame* aRelativeTo, + RectCallback* aCallback, uint32_t aFlags) + : mRelativeTo(aRelativeTo), + mCallback(aCallback), + mFlags(aFlags), + mRelativeToIsRoot(!aRelativeTo->GetParent()), + mRelativeToIsTarget(aRelativeTo == aTargetFrame) {} + + void AddBox(nsIFrame* aFrame) override { + nsRect r; + nsIFrame* outer = SVGUtils::GetOuterSVGFrameAndCoveredRegion(aFrame, &r); + const bool usingSVGOuterFrame = !!outer; + if (!outer) { + outer = aFrame; + switch (mFlags & nsLayoutUtils::RECTS_WHICH_BOX_MASK) { + case nsLayoutUtils::RECTS_USE_CONTENT_BOX: + r = aFrame->GetContentRectRelativeToSelf(); + break; + case nsLayoutUtils::RECTS_USE_PADDING_BOX: + r = aFrame->GetPaddingRectRelativeToSelf(); + break; + case nsLayoutUtils::RECTS_USE_MARGIN_BOX: + r = aFrame->GetMarginRectRelativeToSelf(); + break; + default: // Use the border box + r = aFrame->GetRectRelativeToSelf(); + } + } + if (mFlags & nsLayoutUtils::RECTS_ACCOUNT_FOR_TRANSFORMS) { + const bool isAncestorKnown = [&] { + if (mRelativeToIsRoot) { + return true; + } + if (mRelativeToIsTarget && !mInTargetContinuation) { + return !usingSVGOuterFrame; + } + return false; + }(); + if (isAncestorKnown) { + r = nsLayoutUtils::TransformFrameRectToAncestor(outer, r, mRelativeTo); + } else { + nsLayoutUtils::TransformRect(outer, mRelativeTo, r); + } + } else { + if (aFrame->PresContext() != mRelativeTo->PresContext()) { + r += outer->GetOffsetToCrossDoc(mRelativeTo); + } else { + r += outer->GetOffsetTo(mRelativeTo); + } + } + mCallback->AddRect(r); + } +}; + +struct MOZ_RAII BoxToRectAndText : public BoxToRect { + Sequence<nsString>* mTextList; + + BoxToRectAndText(const nsIFrame* aTargetFrame, const nsIFrame* aRelativeTo, + RectCallback* aCallback, Sequence<nsString>* aTextList, + uint32_t aFlags) + : BoxToRect(aTargetFrame, aRelativeTo, aCallback, aFlags), + mTextList(aTextList) {} + + static void AccumulateText(nsIFrame* aFrame, nsAString& aResult) { + MOZ_ASSERT(aFrame); + + // Get all the text in aFrame and child frames, while respecting + // the content offsets in each of the nsTextFrames. + if (aFrame->IsTextFrame()) { + nsTextFrame* textFrame = static_cast<nsTextFrame*>(aFrame); + + nsIFrame::RenderedText renderedText = textFrame->GetRenderedText( + textFrame->GetContentOffset(), + textFrame->GetContentOffset() + textFrame->GetContentLength(), + nsIFrame::TextOffsetType::OffsetsInContentText, + nsIFrame::TrailingWhitespace::DontTrim); + + aResult.Append(renderedText.mString); + } + + for (nsIFrame* child = aFrame->PrincipalChildList().FirstChild(); child; + child = child->GetNextSibling()) { + AccumulateText(child, aResult); + } + } + + void AddBox(nsIFrame* aFrame) override { + BoxToRect::AddBox(aFrame); + if (mTextList) { + nsString* textForFrame = mTextList->AppendElement(fallible); + if (textForFrame) { + AccumulateText(aFrame, *textForFrame); + } + } + } +}; + +void nsLayoutUtils::GetAllInFlowRects(nsIFrame* aFrame, + const nsIFrame* aRelativeTo, + RectCallback* aCallback, + uint32_t aFlags) { + BoxToRect converter(aFrame, aRelativeTo, aCallback, aFlags); + GetAllInFlowBoxes(aFrame, &converter); +} + +void nsLayoutUtils::GetAllInFlowRectsAndTexts(nsIFrame* aFrame, + const nsIFrame* aRelativeTo, + RectCallback* aCallback, + Sequence<nsString>* aTextList, + uint32_t aFlags) { + BoxToRectAndText converter(aFrame, aRelativeTo, aCallback, aTextList, aFlags); + GetAllInFlowBoxes(aFrame, &converter); +} + +nsLayoutUtils::RectAccumulator::RectAccumulator() : mSeenFirstRect(false) {} + +void nsLayoutUtils::RectAccumulator::AddRect(const nsRect& aRect) { + mResultRect.UnionRect(mResultRect, aRect); + if (!mSeenFirstRect) { + mSeenFirstRect = true; + mFirstRect = aRect; + } +} + +nsLayoutUtils::RectListBuilder::RectListBuilder(DOMRectList* aList) + : mRectList(aList) {} + +void nsLayoutUtils::RectListBuilder::AddRect(const nsRect& aRect) { + RefPtr<DOMRect> rect = new DOMRect(mRectList); + + rect->SetLayoutRect(aRect); + mRectList->Append(rect); +} + +nsIFrame* nsLayoutUtils::GetContainingBlockForClientRect(nsIFrame* aFrame) { + return aFrame->PresShell()->GetRootFrame(); +} + +nsRect nsLayoutUtils::GetAllInFlowRectsUnion(nsIFrame* aFrame, + const nsIFrame* aRelativeTo, + uint32_t aFlags) { + RectAccumulator accumulator; + GetAllInFlowRects(aFrame, aRelativeTo, &accumulator, aFlags); + return accumulator.mResultRect.IsEmpty() ? accumulator.mFirstRect + : accumulator.mResultRect; +} + +nsRect nsLayoutUtils::GetTextShadowRectsUnion( + const nsRect& aTextAndDecorationsRect, nsIFrame* aFrame, uint32_t aFlags) { + const nsStyleText* textStyle = aFrame->StyleText(); + auto shadows = textStyle->mTextShadow.AsSpan(); + if (shadows.IsEmpty()) { + return aTextAndDecorationsRect; + } + + nsRect resultRect = aTextAndDecorationsRect; + int32_t A2D = aFrame->PresContext()->AppUnitsPerDevPixel(); + for (auto& shadow : shadows) { + nsMargin blur = + nsContextBoxBlur::GetBlurRadiusMargin(shadow.blur.ToAppUnits(), A2D); + if ((aFlags & EXCLUDE_BLUR_SHADOWS) && blur != nsMargin(0, 0, 0, 0)) + continue; + + nsRect tmpRect(aTextAndDecorationsRect); + + tmpRect.MoveBy( + nsPoint(shadow.horizontal.ToAppUnits(), shadow.vertical.ToAppUnits())); + tmpRect.Inflate(blur); + + resultRect.UnionRect(resultRect, tmpRect); + } + return resultRect; +} + +enum ObjectDimensionType { eWidth, eHeight }; +static nscoord ComputeMissingDimension( + const nsSize& aDefaultObjectSize, const AspectRatio& aIntrinsicRatio, + const Maybe<nscoord>& aSpecifiedWidth, + const Maybe<nscoord>& aSpecifiedHeight, + ObjectDimensionType aDimensionToCompute) { + // The "default sizing algorithm" computes the missing dimension as follows: + // (source: http://dev.w3.org/csswg/css-images-3/#default-sizing ) + + // 1. "If the object has an intrinsic aspect ratio, the missing dimension of + // the concrete object size is calculated using the intrinsic aspect + // ratio and the present dimension." + if (aIntrinsicRatio) { + // Fill in the missing dimension using the intrinsic aspect ratio. + if (aDimensionToCompute == eWidth) { + return aIntrinsicRatio.ApplyTo(*aSpecifiedHeight); + } + return aIntrinsicRatio.Inverted().ApplyTo(*aSpecifiedWidth); + } + + // 2. "Otherwise, if the missing dimension is present in the object's + // intrinsic dimensions, [...]" + // NOTE: *Skipping* this case, because we already know it's not true -- we're + // in this function because the missing dimension is *not* present in + // the object's intrinsic dimensions. + + // 3. "Otherwise, the missing dimension of the concrete object size is taken + // from the default object size. " + return (aDimensionToCompute == eWidth) ? aDefaultObjectSize.width + : aDefaultObjectSize.height; +} + +/* + * This computes & returns the concrete object size of replaced content, if + * that content were to be rendered with "object-fit: none". (Or, if the + * element has neither an intrinsic height nor width, this method returns an + * empty Maybe<> object.) + * + * As specced... + * http://dev.w3.org/csswg/css-images-3/#valdef-object-fit-none + * ..we use "the default sizing algorithm with no specified size, + * and a default object size equal to the replaced element's used width and + * height." + * + * The default sizing algorithm is described here: + * http://dev.w3.org/csswg/css-images-3/#default-sizing + * Quotes in the function-impl are taken from that ^ spec-text. + * + * Per its final bulleted section: since there's no specified size, + * we run the default sizing algorithm using the object's intrinsic size in + * place of the specified size. But if the object has neither an intrinsic + * height nor an intrinsic width, then we instead return without populating our + * outparam, and we let the caller figure out the size (using a contain + * constraint). + */ +static Maybe<nsSize> MaybeComputeObjectFitNoneSize( + const nsSize& aDefaultObjectSize, const IntrinsicSize& aIntrinsicSize, + const AspectRatio& aIntrinsicRatio) { + // "If the object has an intrinsic height or width, its size is resolved as + // if its intrinsic dimensions were given as the specified size." + // + // So, first we check if we have an intrinsic height and/or width: + const Maybe<nscoord>& specifiedWidth = aIntrinsicSize.width; + const Maybe<nscoord>& specifiedHeight = aIntrinsicSize.height; + + Maybe<nsSize> noneSize; // (the value we'll return) + if (specifiedWidth || specifiedHeight) { + // We have at least one specified dimension; use whichever dimension is + // specified, and compute the other one using our intrinsic ratio, or (if + // no valid ratio) using the default object size. + noneSize.emplace(); + + noneSize->width = + specifiedWidth + ? *specifiedWidth + : ComputeMissingDimension(aDefaultObjectSize, aIntrinsicRatio, + specifiedWidth, specifiedHeight, eWidth); + + noneSize->height = + specifiedHeight + ? *specifiedHeight + : ComputeMissingDimension(aDefaultObjectSize, aIntrinsicRatio, + specifiedWidth, specifiedHeight, eHeight); + } + // [else:] "Otherwise [if there's neither an intrinsic height nor width], its + // size is resolved as a contain constraint against the default object size." + // We'll let our caller do that, to share code & avoid redundant + // computations; so, we return w/out populating noneSize. + return noneSize; +} + +// Computes the concrete object size to render into, as described at +// http://dev.w3.org/csswg/css-images-3/#concrete-size-resolution +static nsSize ComputeConcreteObjectSize(const nsSize& aConstraintSize, + const IntrinsicSize& aIntrinsicSize, + const AspectRatio& aIntrinsicRatio, + StyleObjectFit aObjectFit) { + // Handle default behavior (filling the container) w/ fast early return. + // (Also: if there's no valid intrinsic ratio, then we have the "fill" + // behavior & just use the constraint size.) + if (MOZ_LIKELY(aObjectFit == StyleObjectFit::Fill) || !aIntrinsicRatio) { + return aConstraintSize; + } + + // The type of constraint to compute (cover/contain), if needed: + Maybe<nsImageRenderer::FitType> fitType; + + Maybe<nsSize> noneSize; + if (aObjectFit == StyleObjectFit::None || + aObjectFit == StyleObjectFit::ScaleDown) { + noneSize = MaybeComputeObjectFitNoneSize(aConstraintSize, aIntrinsicSize, + aIntrinsicRatio); + if (!noneSize || aObjectFit == StyleObjectFit::ScaleDown) { + // Need to compute a 'CONTAIN' constraint (either for the 'none' size + // itself, or for comparison w/ the 'none' size to resolve 'scale-down'.) + fitType.emplace(nsImageRenderer::CONTAIN); + } + } else if (aObjectFit == StyleObjectFit::Cover) { + fitType.emplace(nsImageRenderer::COVER); + } else if (aObjectFit == StyleObjectFit::Contain) { + fitType.emplace(nsImageRenderer::CONTAIN); + } + + Maybe<nsSize> constrainedSize; + if (fitType) { + constrainedSize.emplace(nsImageRenderer::ComputeConstrainedSize( + aConstraintSize, aIntrinsicRatio, *fitType)); + } + + // Now, we should have all the sizing information that we need. + switch (aObjectFit) { + // skipping StyleObjectFit::Fill; we handled it w/ early-return. + case StyleObjectFit::Contain: + case StyleObjectFit::Cover: + MOZ_ASSERT(constrainedSize); + return *constrainedSize; + + case StyleObjectFit::None: + if (noneSize) { + return *noneSize; + } + MOZ_ASSERT(constrainedSize); + return *constrainedSize; + + case StyleObjectFit::ScaleDown: + MOZ_ASSERT(constrainedSize); + if (noneSize) { + constrainedSize->width = + std::min(constrainedSize->width, noneSize->width); + constrainedSize->height = + std::min(constrainedSize->height, noneSize->height); + } + return *constrainedSize; + + default: + MOZ_ASSERT_UNREACHABLE("Unexpected enum value for 'object-fit'"); + return aConstraintSize; // fall back to (default) 'fill' behavior + } +} + +// (Helper for HasInitialObjectFitAndPosition, to check +// each "object-position" coord.) +static bool IsCoord50Pct(const LengthPercentage& aCoord) { + return aCoord.ConvertsToPercentage() && aCoord.ToPercentage() == 0.5f; +} + +// Indicates whether the given nsStylePosition has the initial values +// for the "object-fit" and "object-position" properties. +static bool HasInitialObjectFitAndPosition(const nsStylePosition* aStylePos) { + const Position& objectPos = aStylePos->mObjectPosition; + + return aStylePos->mObjectFit == StyleObjectFit::Fill && + IsCoord50Pct(objectPos.horizontal) && IsCoord50Pct(objectPos.vertical); +} + +/* static */ +nsRect nsLayoutUtils::ComputeObjectDestRect(const nsRect& aConstraintRect, + const IntrinsicSize& aIntrinsicSize, + const AspectRatio& aIntrinsicRatio, + const nsStylePosition* aStylePos, + nsPoint* aAnchorPoint) { + // Step 1: Figure out our "concrete object size" + // (the size of the region we'll actually draw our image's pixels into). + nsSize concreteObjectSize = + ComputeConcreteObjectSize(aConstraintRect.Size(), aIntrinsicSize, + aIntrinsicRatio, aStylePos->mObjectFit); + + // Step 2: Figure out how to align that region in the element's content-box. + nsPoint imageTopLeftPt, imageAnchorPt; + nsImageRenderer::ComputeObjectAnchorPoint( + aStylePos->mObjectPosition, aConstraintRect.Size(), concreteObjectSize, + &imageTopLeftPt, &imageAnchorPt); + // Right now, we're with respect to aConstraintRect's top-left point. We add + // that point here, to convert to the same broader coordinate space that + // aConstraintRect is in. + imageTopLeftPt += aConstraintRect.TopLeft(); + imageAnchorPt += aConstraintRect.TopLeft(); + + if (aAnchorPoint) { + // Special-case: if our "object-fit" and "object-position" properties have + // their default values ("object-fit: fill; object-position:50% 50%"), then + // we'll override the calculated imageAnchorPt, and instead use the + // object's top-left corner. + // + // This special case is partly for backwards compatibility (since + // traditionally we've pixel-aligned the top-left corner of e.g. <img> + // elements), and partly because ComputeSnappedDrawingParameters produces + // less error if the anchor point is at the top-left corner. So, all other + // things being equal, we prefer that code path with less error. + if (HasInitialObjectFitAndPosition(aStylePos)) { + *aAnchorPoint = imageTopLeftPt; + } else { + *aAnchorPoint = imageAnchorPt; + } + } + return nsRect(imageTopLeftPt, concreteObjectSize); +} + +already_AddRefed<nsFontMetrics> nsLayoutUtils::GetFontMetricsForFrame( + const nsIFrame* aFrame, float aInflation) { + ComputedStyle* computedStyle = aFrame->Style(); + uint8_t variantWidth = NS_FONT_VARIANT_WIDTH_NORMAL; + if (computedStyle->IsTextCombined()) { + MOZ_ASSERT(aFrame->IsTextFrame()); + auto textFrame = static_cast<const nsTextFrame*>(aFrame); + auto clusters = textFrame->CountGraphemeClusters(); + if (clusters == 2) { + variantWidth = NS_FONT_VARIANT_WIDTH_HALF; + } else if (clusters == 3) { + variantWidth = NS_FONT_VARIANT_WIDTH_THIRD; + } else if (clusters == 4) { + variantWidth = NS_FONT_VARIANT_WIDTH_QUARTER; + } + } + return GetFontMetricsForComputedStyle(computedStyle, aFrame->PresContext(), + aInflation, variantWidth); +} + +already_AddRefed<nsFontMetrics> nsLayoutUtils::GetFontMetricsForComputedStyle( + const ComputedStyle* aComputedStyle, nsPresContext* aPresContext, + float aInflation, uint8_t aVariantWidth) { + WritingMode wm(aComputedStyle); + const nsStyleFont* styleFont = aComputedStyle->StyleFont(); + nsFontMetrics::Params params; + params.language = styleFont->mLanguage; + params.explicitLanguage = styleFont->mExplicitLanguage; + params.orientation = wm.IsVertical() && !wm.IsSideways() + ? nsFontMetrics::eVertical + : nsFontMetrics::eHorizontal; + // pass the user font set object into the device context to + // pass along to CreateFontGroup + params.userFontSet = aPresContext->GetUserFontSet(); + params.textPerf = aPresContext->GetTextPerfMetrics(); + params.featureValueLookup = aPresContext->GetFontFeatureValuesLookup(); + + // When aInflation is 1.0 and we don't require width variant, avoid + // making a local copy of the nsFont. + // This also avoids running font.size through floats when it is large, + // which would be lossy. Fortunately, in such cases, aInflation is + // guaranteed to be 1.0f. + if (aInflation == 1.0f && aVariantWidth == NS_FONT_VARIANT_WIDTH_NORMAL) { + return aPresContext->GetMetricsFor(styleFont->mFont, params); + } + + nsFont font = styleFont->mFont; + MOZ_ASSERT(!IsNaN(float(font.size.ToCSSPixels())), + "Style font should never be NaN"); + font.size.ScaleBy(aInflation); + if (MOZ_UNLIKELY(IsNaN(float(font.size.ToCSSPixels())))) { + font.size = {0}; + } + font.variantWidth = aVariantWidth; + return aPresContext->GetMetricsFor(font, params); +} + +nsIFrame* nsLayoutUtils::FindChildContainingDescendant( + nsIFrame* aParent, nsIFrame* aDescendantFrame) { + nsIFrame* result = aDescendantFrame; + + while (result) { + nsIFrame* parent = result->GetParent(); + if (parent == aParent) { + break; + } + + // The frame is not an immediate child of aParent so walk up another level + result = parent; + } + + return result; +} + +nsBlockFrame* nsLayoutUtils::FindNearestBlockAncestor(nsIFrame* aFrame) { + nsIFrame* nextAncestor; + for (nextAncestor = aFrame->GetParent(); nextAncestor; + nextAncestor = nextAncestor->GetParent()) { + nsBlockFrame* block = do_QueryFrame(nextAncestor); + if (block) return block; + } + return nullptr; +} + +nsIFrame* nsLayoutUtils::GetNonGeneratedAncestor(nsIFrame* aFrame) { + if (!aFrame->HasAnyStateBits(NS_FRAME_GENERATED_CONTENT)) return aFrame; + + nsIFrame* f = aFrame; + do { + f = GetParentOrPlaceholderFor(f); + } while (f->HasAnyStateBits(NS_FRAME_GENERATED_CONTENT)); + return f; +} + +nsIFrame* nsLayoutUtils::GetParentOrPlaceholderFor(const nsIFrame* aFrame) { + if (aFrame->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW) && + !aFrame->GetPrevInFlow()) { + return aFrame->GetProperty(nsIFrame::PlaceholderFrameProperty()); + } + return aFrame->GetParent(); +} + +nsIFrame* nsLayoutUtils::GetParentOrPlaceholderForCrossDoc( + const nsIFrame* aFrame) { + nsIFrame* f = GetParentOrPlaceholderFor(aFrame); + if (f) return f; + return GetCrossDocParentFrameInProcess(aFrame); +} + +nsIFrame* nsLayoutUtils::GetDisplayListParent(nsIFrame* aFrame) { + if (aFrame->HasAnyStateBits(NS_FRAME_IS_PUSHED_FLOAT)) { + return aFrame->GetParent(); + } + return nsLayoutUtils::GetParentOrPlaceholderForCrossDoc(aFrame); +} + +nsIFrame* nsLayoutUtils::GetPrevContinuationOrIBSplitSibling( + const nsIFrame* aFrame) { + if (nsIFrame* result = aFrame->GetPrevContinuation()) { + return result; + } + + if (aFrame->HasAnyStateBits(NS_FRAME_PART_OF_IBSPLIT)) { + // We are the first frame in the continuation chain. Get the ib-split prev + // sibling property stored in us. + return aFrame->GetProperty(nsIFrame::IBSplitPrevSibling()); + } + + return nullptr; +} + +nsIFrame* nsLayoutUtils::GetNextContinuationOrIBSplitSibling( + const nsIFrame* aFrame) { + if (nsIFrame* result = aFrame->GetNextContinuation()) { + return result; + } + + if (aFrame->HasAnyStateBits(NS_FRAME_PART_OF_IBSPLIT)) { + // We only store the ib-split sibling annotation with the first frame in the + // continuation chain. + return aFrame->FirstContinuation()->GetProperty(nsIFrame::IBSplitSibling()); + } + + return nullptr; +} + +nsIFrame* nsLayoutUtils::FirstContinuationOrIBSplitSibling( + const nsIFrame* aFrame) { + nsIFrame* result = aFrame->FirstContinuation(); + + if (result->HasAnyStateBits(NS_FRAME_PART_OF_IBSPLIT)) { + while (auto* f = result->GetProperty(nsIFrame::IBSplitPrevSibling())) { + result = f; + } + } + + return result; +} + +nsIFrame* nsLayoutUtils::LastContinuationOrIBSplitSibling( + const nsIFrame* aFrame) { + nsIFrame* result = aFrame->FirstContinuation(); + + if (result->HasAnyStateBits(NS_FRAME_PART_OF_IBSPLIT)) { + while (auto* f = result->GetProperty(nsIFrame::IBSplitSibling())) { + result = f; + } + } + + return result->LastContinuation(); +} + +bool nsLayoutUtils::IsFirstContinuationOrIBSplitSibling( + const nsIFrame* aFrame) { + if (aFrame->GetPrevContinuation()) { + return false; + } + if (aFrame->HasAnyStateBits(NS_FRAME_PART_OF_IBSPLIT) && + aFrame->GetProperty(nsIFrame::IBSplitPrevSibling())) { + return false; + } + + return true; +} + +bool nsLayoutUtils::IsViewportScrollbarFrame(nsIFrame* aFrame) { + if (!aFrame) return false; + + nsIFrame* rootScrollFrame = aFrame->PresShell()->GetRootScrollFrame(); + if (!rootScrollFrame) return false; + + nsIScrollableFrame* rootScrollableFrame = do_QueryFrame(rootScrollFrame); + NS_ASSERTION(rootScrollableFrame, "The root scorollable frame is null"); + + if (!IsProperAncestorFrame(rootScrollFrame, aFrame)) return false; + + nsIFrame* rootScrolledFrame = rootScrollableFrame->GetScrolledFrame(); + return !(rootScrolledFrame == aFrame || + IsProperAncestorFrame(rootScrolledFrame, aFrame)); +} + +/** + * Use only for paddings / widths / heights, since it clamps negative calc() to + * 0. + */ +template <typename LengthPercentageLike> +static bool GetAbsoluteCoord(const LengthPercentageLike& aStyle, + nscoord& aResult) { + if (!aStyle.ConvertsToLength()) { + return false; + } + aResult = std::max(0, aStyle.ToLength()); + return true; +} + +static nscoord GetBSizePercentBasisAdjustment(StyleBoxSizing aBoxSizing, + nsIFrame* aFrame, + bool aHorizontalAxis, + bool aResolvesAgainstPaddingBox); + +static bool GetPercentBSize(const LengthPercentage& aStyle, nsIFrame* aFrame, + bool aHorizontalAxis, nscoord& aResult); + +// Only call on style coords for which GetAbsoluteCoord returned false. +template <typename SizeOrMaxSize> +static bool GetPercentBSize(const SizeOrMaxSize& aStyle, nsIFrame* aFrame, + bool aHorizontalAxis, nscoord& aResult) { + if (!aStyle.IsLengthPercentage()) { + return false; + } + return GetPercentBSize(aStyle.AsLengthPercentage(), aFrame, aHorizontalAxis, + aResult); +} + +static bool GetPercentBSize(const LengthPercentage& aStyle, nsIFrame* aFrame, + bool aHorizontalAxis, nscoord& aResult) { + if (!aStyle.HasPercent()) { + return false; + } + + MOZ_ASSERT(!aStyle.ConvertsToLength(), + "GetAbsoluteCoord should have handled this"); + + // During reflow, nsHTMLScrollFrame::ReflowScrolledFrame uses + // SetComputedHeight on the reflow input for its child to propagate its + // computed height to the scrolled content. So here we skip to the scroll + // frame that contains this scrolled content in order to get the same + // behavior as layout when computing percentage heights. + nsIFrame* f = aFrame->GetContainingBlock(nsIFrame::SKIP_SCROLLED_FRAME); + if (!f) { + MOZ_ASSERT_UNREACHABLE("top of frame tree not a containing block"); + return false; + } + + WritingMode wm = f->GetWritingMode(); + + const nsStylePosition* pos = f->StylePosition(); + const auto& bSizeCoord = pos->BSize(wm); + nscoord h; + if (!GetAbsoluteCoord(bSizeCoord, h) && + !GetPercentBSize(bSizeCoord, f, aHorizontalAxis, h)) { + LayoutFrameType fType = f->Type(); + if (fType != LayoutFrameType::Viewport && + fType != LayoutFrameType::Canvas && + fType != LayoutFrameType::PageContent) { + // There's no basis for the percentage height, so it acts like auto. + // Should we consider a max-height < min-height pair a basis for + // percentage heights? The spec is somewhat unclear, and not doing + // so is simpler and avoids troubling discontinuities in behavior, + // so I'll choose not to. -LDB + return false; + } + // For the viewport, canvas, and page-content kids, the percentage + // basis is just the parent block-size. + h = f->BSize(wm); + if (h == NS_UNCONSTRAINEDSIZE) { + // We don't have a percentage basis after all + return false; + } + } + + const auto& maxBSizeCoord = pos->MaxBSize(wm); + + nscoord maxh; + if (GetAbsoluteCoord(maxBSizeCoord, maxh) || + GetPercentBSize(maxBSizeCoord, f, aHorizontalAxis, maxh)) { + if (maxh < h) h = maxh; + } + + const auto& minBSizeCoord = pos->MinBSize(wm); + + nscoord minh; + if (GetAbsoluteCoord(minBSizeCoord, minh) || + GetPercentBSize(minBSizeCoord, f, aHorizontalAxis, minh)) { + if (minh > h) { + h = minh; + } + } + + // If we're an abspos box, percentages in that case resolve against the + // padding box. + // + // TODO: This could conceivably cause some problems with fieldsets (which are + // the other place that wants to ignore padding), but solving that here + // without hardcoding a check for f being a fieldset-content frame is a bit of + // a pain. + const bool resolvesAgainstPaddingBox = aFrame->IsAbsolutelyPositioned(); + h += GetBSizePercentBasisAdjustment(pos->mBoxSizing, f, aHorizontalAxis, + resolvesAgainstPaddingBox); + + aResult = std::max(aStyle.Resolve(std::max(h, 0)), 0); + return true; +} + +// Return true if aStyle can be resolved to a definite value and if so +// return that value in aResult. +static bool GetDefiniteSize(const LengthPercentage& aStyle, nsIFrame* aFrame, + bool aIsInlineAxis, + const Maybe<LogicalSize>& aPercentageBasis, + nscoord* aResult) { + if (aStyle.ConvertsToLength()) { + *aResult = aStyle.ToLength(); + return true; + } + + if (!aPercentageBasis) { + return false; + } + + auto wm = aFrame->GetWritingMode(); + nscoord pb = aIsInlineAxis ? aPercentageBasis.value().ISize(wm) + : aPercentageBasis.value().BSize(wm); + if (pb == NS_UNCONSTRAINEDSIZE) { + return false; + } + *aResult = std::max(0, aStyle.Resolve(pb)); + return true; +} + +// Return true if aStyle can be resolved to a definite value and if so +// return that value in aResult. +template <typename SizeOrMaxSize> +static bool GetDefiniteSize(const SizeOrMaxSize& aStyle, nsIFrame* aFrame, + bool aIsInlineAxis, + const Maybe<LogicalSize>& aPercentageBasis, + nscoord* aResult) { + if (!aStyle.IsLengthPercentage()) { + return false; + } + return GetDefiniteSize(aStyle.AsLengthPercentage(), aFrame, aIsInlineAxis, + aPercentageBasis, aResult); +} + +// NOTE: this function will be replaced by GetDefiniteSizeTakenByBoxSizing (bug +// 1363918). Please do not add new uses of this function. +// +// Get the amount of space to add or subtract out of aFrame's 'block-size' or +// property value due its borders and paddings, given the box-sizing value in +// aBoxSizing. +// +// aHorizontalAxis is true if our inline direction is horizontal and our block +// direction is vertical. aResolvesAgainstPaddingBox is true if padding should +// be added or not removed. +static nscoord GetBSizePercentBasisAdjustment(StyleBoxSizing aBoxSizing, + nsIFrame* aFrame, + bool aHorizontalAxis, + bool aResolvesAgainstPaddingBox) { + nscoord adjustment = 0; + if (aBoxSizing == StyleBoxSizing::Border) { + const auto& border = aFrame->StyleBorder()->GetComputedBorder(); + adjustment -= aHorizontalAxis ? border.TopBottom() : border.LeftRight(); + } + if ((aBoxSizing == StyleBoxSizing::Border) == !aResolvesAgainstPaddingBox) { + const auto& stylePadding = aFrame->StylePadding()->mPadding; + const LengthPercentage& paddingStart = + stylePadding.Get(aHorizontalAxis ? eSideTop : eSideLeft); + const LengthPercentage& paddingEnd = + stylePadding.Get(aHorizontalAxis ? eSideBottom : eSideRight); + nscoord pad; + // XXXbz Calling GetPercentBSize on padding values looks bogus, since + // percent padding is always a percentage of the inline-size of the + // containing block. We should perhaps just treat non-absolute paddings + // here as 0 instead, except that in some cases the width may in fact be + // known. See bug 1231059. + if (GetAbsoluteCoord(paddingStart, pad) || + GetPercentBSize(paddingStart, aFrame, aHorizontalAxis, pad)) { + adjustment += aResolvesAgainstPaddingBox ? pad : -pad; + } + if (GetAbsoluteCoord(paddingEnd, pad) || + GetPercentBSize(paddingEnd, aFrame, aHorizontalAxis, pad)) { + adjustment += aResolvesAgainstPaddingBox ? pad : -pad; + } + } + return adjustment; +} + +// Get the amount of space taken out of aFrame's content area due to its +// borders and paddings given the box-sizing value in aBoxSizing. We don't +// get aBoxSizing from the frame because some callers want to compute this for +// specific box-sizing values. +// aIsInlineAxis is true if we're computing for aFrame's inline axis. +// aIgnorePadding is true if padding should be ignored. +static nscoord GetDefiniteSizeTakenByBoxSizing( + StyleBoxSizing aBoxSizing, nsIFrame* aFrame, bool aIsInlineAxis, + bool aIgnorePadding, const Maybe<LogicalSize>& aPercentageBasis) { + nscoord sizeTakenByBoxSizing = 0; + if (MOZ_UNLIKELY(aBoxSizing == StyleBoxSizing::Border)) { + const bool isHorizontalAxis = + aIsInlineAxis == !aFrame->GetWritingMode().IsVertical(); + const nsStyleBorder* styleBorder = aFrame->StyleBorder(); + sizeTakenByBoxSizing = isHorizontalAxis + ? styleBorder->GetComputedBorder().LeftRight() + : styleBorder->GetComputedBorder().TopBottom(); + if (!aIgnorePadding) { + const auto& stylePadding = aFrame->StylePadding()->mPadding; + const LengthPercentage& pStart = + stylePadding.Get(isHorizontalAxis ? eSideLeft : eSideTop); + const LengthPercentage& pEnd = + stylePadding.Get(isHorizontalAxis ? eSideRight : eSideBottom); + nscoord pad; + // XXXbz Calling GetPercentBSize on padding values looks bogus, since + // percent padding is always a percentage of the inline-size of the + // containing block. We should perhaps just treat non-absolute paddings + // here as 0 instead, except that in some cases the width may in fact be + // known. See bug 1231059. + if (GetDefiniteSize(pStart, aFrame, aIsInlineAxis, aPercentageBasis, + &pad) || + (aPercentageBasis.isNothing() && + GetPercentBSize(pStart, aFrame, isHorizontalAxis, pad))) { + sizeTakenByBoxSizing += pad; + } + if (GetDefiniteSize(pEnd, aFrame, aIsInlineAxis, aPercentageBasis, + &pad) || + (aPercentageBasis.isNothing() && + GetPercentBSize(pEnd, aFrame, isHorizontalAxis, pad))) { + sizeTakenByBoxSizing += pad; + } + } + } + return sizeTakenByBoxSizing; +} + +/** + * Handles only max-content and min-content, and + * -moz-fit-content for min-width and max-width, since the others + * (-moz-fit-content for width, and -moz-available) have no effect on + * intrinsic widths. + */ +static bool GetIntrinsicCoord(nsIFrame::ExtremumLength aStyle, + gfxContext* aRenderingContext, nsIFrame* aFrame, + Maybe<nscoord> aInlineSizeFromAspectRatio, + nsIFrame::SizeProperty aProperty, + nscoord aContentBoxToBoxSizingDiff, + nscoord& aResult) { + if (aStyle == nsIFrame::ExtremumLength::MozAvailable) { + return false; + } + + if (aStyle == nsIFrame::ExtremumLength::FitContentFunction) { + // fit-content() should be handled by the caller. + return false; + } + + if (aStyle == nsIFrame::ExtremumLength::FitContent) { + switch (aProperty) { + case nsIFrame::SizeProperty::Size: + // handle like 'width: auto' + return false; + case nsIFrame::SizeProperty::MaxSize: + // constrain large 'width' values down to max-content + aStyle = nsIFrame::ExtremumLength::MaxContent; + break; + case nsIFrame::SizeProperty::MinSize: + // constrain small 'width' or 'max-width' values up to min-content + aStyle = nsIFrame::ExtremumLength::MinContent; + break; + } + } + + NS_ASSERTION(aStyle == nsIFrame::ExtremumLength::MinContent || + aStyle == nsIFrame::ExtremumLength::MaxContent, + "should have reduced everything remaining to one of these"); + + // If aFrame is a container for font size inflation, then shrink + // wrapping inside of it should not apply font size inflation. + AutoMaybeDisableFontInflation an(aFrame); + + if (aInlineSizeFromAspectRatio) { + aResult = *aInlineSizeFromAspectRatio; + } else if (aStyle == nsIFrame::ExtremumLength::MaxContent) { + aResult = aFrame->GetPrefISize(aRenderingContext); + } else { + aResult = aFrame->GetMinISize(aRenderingContext); + } + + aResult += aContentBoxToBoxSizingDiff; + + return true; +} + +template <typename SizeOrMaxSize> +static bool GetIntrinsicCoord(const SizeOrMaxSize& aStyle, + gfxContext* aRenderingContext, nsIFrame* aFrame, + Maybe<nscoord> aInlineSizeFromAspectRatio, + nsIFrame::SizeProperty aProperty, + nscoord aContentBoxToBoxSizingDiff, + nscoord& aResult) { + auto length = nsIFrame::ToExtremumLength(aStyle); + if (!length) { + return false; + } + return GetIntrinsicCoord(*length, aRenderingContext, aFrame, + aInlineSizeFromAspectRatio, aProperty, + aContentBoxToBoxSizingDiff, aResult); +} + +#undef DEBUG_INTRINSIC_WIDTH + +#ifdef DEBUG_INTRINSIC_WIDTH +static int32_t gNoiseIndent = 0; +#endif + +static nscoord GetFitContentSizeForMaxOrPreferredSize( + const IntrinsicISizeType aType, const nsIFrame::SizeProperty aProperty, + const nsIFrame* aFrame, const LengthPercentage& aStyleSize, + const nscoord aInitialValue, const nscoord aMinContentSize, + const nscoord aMaxContentSize) { + MOZ_ASSERT(aProperty != nsIFrame::SizeProperty::MinSize); + + nscoord size = NS_UNCONSTRAINEDSIZE; + // 1. Treat fit-content()'s arg as a plain LengthPercentage + // However, we have to handle the cyclic percentage contribution first. + // + // https://drafts.csswg.org/css-sizing-3/#cyclic-percentage-contribution + if (aType == IntrinsicISizeType::MinISize && + aFrame->IsPercentageResolvedAgainstZero(aStyleSize, aProperty)) { + // Case (c) in the spec. + // FIXME: This doesn't follow the spec for calc(). We should fix this in + // Bug 1463700. + size = 0; + } else if (!GetAbsoluteCoord(aStyleSize, size)) { + // As initial value. Case (a) and (b) in the spec. + size = aInitialValue; + } + + // 2. Clamp size by min-content and max-content. + return std::max(aMinContentSize, std::min(aMaxContentSize, size)); +} + +/** + * Add aOffsets which describes what to add on outside of the content box + * aContentSize (controlled by 'box-sizing') and apply min/max properties. + * We have to account for these properties after getting all the offsets + * (margin, border, padding) because percentages do not operate linearly. + * Doing this is ok because although percentages aren't handled linearly, + * they are handled monotonically. + * + * @param aContentSize the content size calculated so far + (@see IntrinsicForContainer) + * @param aContentMinSize ditto min content size + * @param aStyleSize a 'width' or 'height' property value + * @param aFixedMinSize if aStyleMinSize is a definite size then this points to + * the value, otherwise nullptr + * @param aStyleMinSize a 'min-width' or 'min-height' property value + * @param aFixedMaxSize if aStyleMaxSize is a definite size then this points to + * the value, otherwise nullptr + * @param aStyleMaxSize a 'max-width' or 'max-height' property value + * @param aInlineSizeFromAspectRatio the content-box inline size computed from + * aspect-ratio and the definite block size. + * We use this value to resolve + * {min|max}-content. + * @param aFlags same as for IntrinsicForContainer + * @param aContainerWM the container's WM + */ +static nscoord AddIntrinsicSizeOffset( + gfxContext* aRenderingContext, nsIFrame* aFrame, + const nsIFrame::IntrinsicSizeOffsetData& aOffsets, IntrinsicISizeType aType, + StyleBoxSizing aBoxSizing, nscoord aContentSize, nscoord aContentMinSize, + const StyleSize& aStyleSize, const nscoord* aFixedMinSize, + const StyleSize& aStyleMinSize, const nscoord* aFixedMaxSize, + const StyleMaxSize& aStyleMaxSize, + Maybe<nscoord> aInlineSizeFromAspectRatio, uint32_t aFlags, + PhysicalAxis aAxis) { + nscoord result = aContentSize; + nscoord min = aContentMinSize; + nscoord coordOutsideSize = 0; + nscoord contentBoxToBoxSizingDiff = 0; + + if (!(aFlags & nsLayoutUtils::IGNORE_PADDING)) { + coordOutsideSize += aOffsets.padding; + } + + coordOutsideSize += aOffsets.border; + + if (aBoxSizing == StyleBoxSizing::Border) { + // Store the padding of the box so we can pass it into + // functions that works with content box-sizing. + contentBoxToBoxSizingDiff = coordOutsideSize; + + min += coordOutsideSize; + result = NSCoordSaturatingAdd(result, coordOutsideSize); + + coordOutsideSize = 0; + } + + coordOutsideSize += aOffsets.margin; + + min += coordOutsideSize; + + // Compute min-content/max-content for fit-content(). + nscoord minContent = 0; + nscoord maxContent = NS_UNCONSTRAINEDSIZE; + if (aStyleSize.IsFitContentFunction() || + aStyleMaxSize.IsFitContentFunction() || + aStyleMinSize.IsFitContentFunction()) { + if (aInlineSizeFromAspectRatio) { + minContent = maxContent = *aInlineSizeFromAspectRatio; + } else { + minContent = aFrame->GetMinISize(aRenderingContext); + maxContent = aFrame->GetPrefISize(aRenderingContext); + } + minContent += contentBoxToBoxSizingDiff; + maxContent += contentBoxToBoxSizingDiff; + } + + // Compute size. + nscoord size = NS_UNCONSTRAINEDSIZE; + if (aType == IntrinsicISizeType::MinISize && + aFrame->IsPercentageResolvedAgainstZero(aStyleSize, aStyleMaxSize)) { + // XXX bug 1463700: this doesn't handle calc() according to spec + result = 0; // let |min| handle padding/border/margin + } else if (GetAbsoluteCoord(aStyleSize, size) || + GetIntrinsicCoord(aStyleSize, aRenderingContext, aFrame, + aInlineSizeFromAspectRatio, + nsIFrame::SizeProperty::Size, + contentBoxToBoxSizingDiff, size)) { + result = size + coordOutsideSize; + } else if (aStyleSize.IsFitContentFunction()) { + // |result| here is the content size or border size, depends on + // StyleBoxSizing. We use it as the initial value when handling the cyclic + // percentage. + nscoord initial = result; + nscoord fitContentFuncSize = GetFitContentSizeForMaxOrPreferredSize( + aType, nsIFrame::SizeProperty::Size, aFrame, + aStyleSize.AsFitContentFunction(), initial, minContent, maxContent); + // Add border and padding. + result = NSCoordSaturatingAdd(fitContentFuncSize, coordOutsideSize); + } else { + result = NSCoordSaturatingAdd(result, coordOutsideSize); + } + + // Compute max-size. + nscoord maxSize = aFixedMaxSize ? *aFixedMaxSize : 0; + if (aFixedMaxSize || GetIntrinsicCoord(aStyleMaxSize, aRenderingContext, + aFrame, aInlineSizeFromAspectRatio, + nsIFrame::SizeProperty::MaxSize, + contentBoxToBoxSizingDiff, maxSize)) { + maxSize += coordOutsideSize; + if (result > maxSize) { + result = maxSize; + } + } else if (aStyleMaxSize.IsFitContentFunction()) { + nscoord fitContentFuncSize = GetFitContentSizeForMaxOrPreferredSize( + aType, nsIFrame::SizeProperty::MaxSize, aFrame, + aStyleMaxSize.AsFitContentFunction(), NS_UNCONSTRAINEDSIZE, minContent, + maxContent); + maxSize = NSCoordSaturatingAdd(fitContentFuncSize, coordOutsideSize); + if (result > maxSize) { + result = maxSize; + } + } + + // Compute min-size. + nscoord minSize = aFixedMinSize ? *aFixedMinSize : 0; + if (aFixedMinSize || GetIntrinsicCoord(aStyleMinSize, aRenderingContext, + aFrame, aInlineSizeFromAspectRatio, + nsIFrame::SizeProperty::MinSize, + contentBoxToBoxSizingDiff, minSize)) { + minSize += coordOutsideSize; + if (result < minSize) { + result = minSize; + } + } else if (aStyleMinSize.IsFitContentFunction()) { + if (!GetAbsoluteCoord(aStyleMinSize.AsFitContentFunction(), minSize)) { + // FIXME: Bug 1463700, we should resolve only the percentage part to 0 + // such as min-width: fit-content(calc(50% + 50px)). + minSize = 0; + } + nscoord fitContentFuncSize = + std::max(minContent, std::min(maxContent, minSize)); + minSize = NSCoordSaturatingAdd(fitContentFuncSize, coordOutsideSize); + if (result < minSize) { + result = minSize; + } + } + + if (result < min) { + result = min; + } + + const nsStyleDisplay* disp = aFrame->StyleDisplay(); + if (aFrame->IsThemed(disp)) { + nsPresContext* pc = aFrame->PresContext(); + LayoutDeviceIntSize devSize = pc->Theme()->GetMinimumWidgetSize( + pc, aFrame, disp->EffectiveAppearance()); + nscoord themeSize = pc->DevPixelsToAppUnits( + aAxis == eAxisVertical ? devSize.height : devSize.width); + // GetMinimumWidgetSize() returns a border-box width. + themeSize += aOffsets.margin; + if (themeSize > result) { + result = themeSize; + } + } + return result; +} + +static void AddStateBitToAncestors(nsIFrame* aFrame, nsFrameState aBit) { + for (nsIFrame* f = aFrame; f; f = f->GetParent()) { + if (f->HasAnyStateBits(aBit)) { + break; + } + f->AddStateBits(aBit); + } +} + +/* static */ +nscoord nsLayoutUtils::IntrinsicForAxis( + PhysicalAxis aAxis, gfxContext* aRenderingContext, nsIFrame* aFrame, + IntrinsicISizeType aType, const Maybe<LogicalSize>& aPercentageBasis, + uint32_t aFlags, nscoord aMarginBoxMinSizeClamp) { + MOZ_ASSERT(aFrame, "null frame"); + MOZ_ASSERT(aFrame->GetParent(), + "IntrinsicForAxis called on frame not in tree"); + MOZ_ASSERT(aFrame->GetParent()->Type() != LayoutFrameType::GridContainer || + aPercentageBasis.isSome(), + "grid layout should always pass a percentage basis"); + + const bool horizontalAxis = MOZ_LIKELY(aAxis == eAxisHorizontal); +#ifdef DEBUG_INTRINSIC_WIDTH + nsIFrame::IndentBy(stderr, gNoiseIndent); + aFrame->ListTag(stderr); + printf_stderr(" %s %s intrinsic size for container:\n", + aType == IntrinsicISizeType::MinISize ? "min" : "pref", + horizontalAxis ? "horizontal" : "vertical"); +#endif + + // If aFrame is a container for font size inflation, then shrink + // wrapping inside of it should not apply font size inflation. + AutoMaybeDisableFontInflation an(aFrame); + + // We want the size this frame will contribute to the parent's inline-size, + // so we work in the parent's writing mode; but if aFrame is orthogonal to + // its parent, we'll need to look at its BSize instead of min/pref-ISize. + const nsStylePosition* stylePos = aFrame->StylePosition(); + StyleBoxSizing boxSizing = stylePos->mBoxSizing; + + StyleSize styleMinISize = + horizontalAxis ? stylePos->mMinWidth : stylePos->mMinHeight; + StyleSize styleISize = + (aFlags & MIN_INTRINSIC_ISIZE) + ? styleMinISize + : (horizontalAxis ? stylePos->mWidth : stylePos->mHeight); + MOZ_ASSERT(!(aFlags & MIN_INTRINSIC_ISIZE) || styleISize.IsAuto() || + nsIFrame::ToExtremumLength(styleISize), + "should only use MIN_INTRINSIC_ISIZE for intrinsic values"); + StyleMaxSize styleMaxISize = + horizontalAxis ? stylePos->mMaxWidth : stylePos->mMaxHeight; + + PhysicalAxis ourInlineAxis = + aFrame->GetWritingMode().PhysicalAxis(eLogicalAxisInline); + const bool isInlineAxis = aAxis == ourInlineAxis; + + auto resetIfKeywords = [](StyleSize& aSize, StyleSize& aMinSize, + StyleMaxSize& aMaxSize) { + if (!aSize.IsLengthPercentage()) { + aSize = StyleSize::Auto(); + } + if (!aMinSize.IsLengthPercentage()) { + aMinSize = StyleSize::Auto(); + } + if (!aMaxSize.IsLengthPercentage()) { + aMaxSize = StyleMaxSize::None(); + } + }; + // According to the spec, max-content and min-content should behave as the + // property's initial values in block axis. + // It also make senses to use the initial values for -moz-fit-content and + // -moz-available for intrinsic size in block axis. Therefore, we reset them + // if needed. + if (!isInlineAxis) { + resetIfKeywords(styleISize, styleMinISize, styleMaxISize); + } + + // We build up two values starting with the content box, and then + // adding padding, border and margin. The result is normally + // |result|. Then, when we handle 'width', 'min-width', and + // 'max-width', we use the results we've been building in |min| as a + // minimum, overriding 'min-width'. This ensures two things: + // * that we don't let a value of 'box-sizing' specifying a width + // smaller than the padding/border inside the box-sizing box give + // a content width less than zero + // * that we prevent tables from becoming smaller than their + // intrinsic minimum width + nscoord result = 0, min = 0; + + nscoord maxISize; + bool haveFixedMaxISize = GetAbsoluteCoord(styleMaxISize, maxISize); + nscoord minISize; + + // Treat "min-width: auto" as 0. + bool haveFixedMinISize; + if (styleMinISize.IsAuto()) { + // NOTE: Technically, "auto" is supposed to behave like "min-content" on + // flex items. However, we don't need to worry about that here, because + // flex items' min-sizes are intentionally ignored until the flex + // container explicitly considers them during space distribution. + minISize = 0; + haveFixedMinISize = true; + } else { + haveFixedMinISize = GetAbsoluteCoord(styleMinISize, minISize); + } + + auto childWM = aFrame->GetWritingMode(); + nscoord pmPercentageBasis = NS_UNCONSTRAINEDSIZE; + if (aPercentageBasis.isSome()) { + // The padding/margin percentage basis is the inline-size in the parent's + // writing-mode. + pmPercentageBasis = + aFrame->GetParent()->GetWritingMode().IsOrthogonalTo(childWM) + ? aPercentageBasis->BSize(childWM) + : aPercentageBasis->ISize(childWM); + } + nsIFrame::IntrinsicSizeOffsetData offsets = + MOZ_LIKELY(isInlineAxis) + ? aFrame->IntrinsicISizeOffsets(pmPercentageBasis) + : aFrame->IntrinsicBSizeOffsets(pmPercentageBasis); + + auto getContentBoxSizeToBoxSizingAdjust = + [childWM, &offsets, &aFrame, isInlineAxis, + pmPercentageBasis](const StyleBoxSizing aBoxSizing) { + return aBoxSizing == StyleBoxSizing::Border + ? LogicalSize(childWM, + (isInlineAxis ? offsets + : aFrame->IntrinsicISizeOffsets( + pmPercentageBasis)) + .BorderPadding(), + (!isInlineAxis ? offsets + : aFrame->IntrinsicBSizeOffsets( + pmPercentageBasis)) + .BorderPadding()) + : LogicalSize(childWM); + }; + + Maybe<nscoord> inlineSizeFromAspectRatio; + Maybe<LogicalSize> contentBoxSizeToBoxSizingAdjust; + + const bool ignorePadding = + (aFlags & IGNORE_PADDING) || aFrame->IsAbsolutelyPositioned(); + + // If we have a specified width (or a specified 'min-width' greater + // than the specified 'max-width', which works out to the same thing), + // don't even bother getting the frame's intrinsic width, because in + // this case GetAbsoluteCoord(styleISize, w) will always succeed, so + // we'll never need the intrinsic dimensions. + if (styleISize.IsMaxContent() || styleISize.IsMinContent()) { + MOZ_ASSERT(isInlineAxis); + // -moz-fit-content and -moz-available enumerated widths compute intrinsic + // widths just like auto. + // For max-content and min-content, we handle them like + // specified widths, but ignore box-sizing. + boxSizing = StyleBoxSizing::Content; + } else if (!styleISize.ConvertsToLength() && + !(styleISize.IsFitContentFunction() && + styleISize.AsFitContentFunction().ConvertsToLength()) && + !(haveFixedMinISize && haveFixedMaxISize && + maxISize <= minISize)) { +#ifdef DEBUG_INTRINSIC_WIDTH + ++gNoiseIndent; +#endif + if (MOZ_UNLIKELY(!isInlineAxis)) { + IntrinsicSize intrinsicSize = aFrame->GetIntrinsicSize(); + const auto& intrinsicBSize = + horizontalAxis ? intrinsicSize.width : intrinsicSize.height; + if (intrinsicBSize) { + result = *intrinsicBSize; + } else { + // We don't have an intrinsic bsize and we need aFrame's block-dir size. + if (aFlags & BAIL_IF_REFLOW_NEEDED) { + return NS_INTRINSIC_ISIZE_UNKNOWN; + } + // XXX Unfortunately, we probably don't know this yet, so this is + // wrong... but it's not clear what we should do. If aFrame's inline + // size hasn't been determined yet, we can't necessarily figure out its + // block size either. For now, authors who put orthogonal elements into + // things like buttons or table cells may have to explicitly provide + // sizes rather than expecting intrinsic sizing to work "perfectly" in + // underspecified cases. + result = aFrame->BSize(); + } + } else { + result = aType == IntrinsicISizeType::MinISize + ? aFrame->GetMinISize(aRenderingContext) + : aFrame->GetPrefISize(aRenderingContext); + } +#ifdef DEBUG_INTRINSIC_WIDTH + --gNoiseIndent; + nsIFrame::IndentBy(stderr, gNoiseIndent); + aFrame->ListTag(stderr); + printf_stderr(" %s %s intrinsic size from frame is %d.\n", + aType == IntrinsicISizeType::MinISize ? "min" : "pref", + horizontalAxis ? "horizontal" : "vertical", result); +#endif + + // Handle elements with an intrinsic ratio (or size) and a specified + // height, min-height, or max-height. + // NOTE: + // 1. We treat "min-height:auto" as "0" for the purpose of this code, + // since that's what it means in all cases except for on flex items -- and + // even there, we're supposed to ignore it (i.e. treat it as 0) until the + // flex container explicitly considers it. + // 2. The 'B' in |styleBSize|, |styleMinBSize|, and |styleMaxBSize| + // represents the ratio-determining axis of |aFrame|. It could be the inline + // axis or the block axis of |aFrame|. (So we are calculating the size + // along the ratio-dependent axis in this if-branch.) + StyleSize styleBSize = + horizontalAxis ? stylePos->mHeight : stylePos->mWidth; + StyleSize styleMinBSize = + horizontalAxis ? stylePos->mMinHeight : stylePos->mMinWidth; + StyleMaxSize styleMaxBSize = + horizontalAxis ? stylePos->mMaxHeight : stylePos->mMaxWidth; + + // According to the spec, max-content and min-content should behave as the + // property's initial values in block axis. + // It also make senses to use the initial values for -moz-fit-content and + // -moz-available for intrinsic size in block axis. Therefore, we reset them + // if needed. + if (isInlineAxis) { + resetIfKeywords(styleBSize, styleMinBSize, styleMaxBSize); + } + + // If our BSize or min/max-BSize properties are set to values that we can + // resolve and that will impose a constraint when transferred through our + // aspect ratio (if we have one), then compute and apply that constraint. + // + // (Note: This helper-bool & lambda just let us optimize away the actual + // transferring-and-clamping arithmetic, for the common case where we can + // tell that none of the block-axis size properties establish a meaningful + // transferred constraint.) + const bool mightHaveBlockAxisConstraintToTransfer = [&] { + if (!styleBSize.BehavesLikeInitialValueOnBlockAxis()) { + return true; // BSize property might have a constraint to transfer. + } + // Check for min-BSize values that would obviously produce zero in the + // transferring logic that follows; zero is trivially-ignorable as a + // transferred lower-bound. (These include the the property's initial + // value, explicit 0, and values that are equivalent to these.) + bool minBSizeHasNoConstraintToTransfer = + styleMinBSize.BehavesLikeInitialValueOnBlockAxis() || + (styleMinBSize.IsLengthPercentage() && + styleMinBSize.AsLengthPercentage().IsDefinitelyZero()); + if (!minBSizeHasNoConstraintToTransfer) { + return true; // min-BSize property might have a constraint to transfer. + } + if (!styleMaxBSize.BehavesLikeInitialValueOnBlockAxis()) { + return true; // max-BSize property might have a constraint to transfer. + } + return false; + }(); + if (mightHaveBlockAxisConstraintToTransfer) { + if (AspectRatio ratio = aFrame->GetAspectRatio()) { + AddStateBitToAncestors( + aFrame, NS_FRAME_DESCENDANT_INTRINSIC_ISIZE_DEPENDS_ON_BSIZE); + + nscoord bSizeTakenByBoxSizing = GetDefiniteSizeTakenByBoxSizing( + boxSizing, aFrame, !isInlineAxis, ignorePadding, aPercentageBasis); + contentBoxSizeToBoxSizingAdjust.emplace( + getContentBoxSizeToBoxSizingAdjust(boxSizing)); + // NOTE: This is only the minContentSize if we've been passed + // MIN_INTRINSIC_ISIZE (which is fine, because this should only be used + // inside a check for that flag). + nscoord minContentSize = result; + nscoord h; + if (GetDefiniteSize(styleBSize, aFrame, !isInlineAxis, aPercentageBasis, + &h) || + (aPercentageBasis.isNothing() && + GetPercentBSize(styleBSize, aFrame, horizontalAxis, h))) { + h = std::max(0, h - bSizeTakenByBoxSizing); + // We are computing the size of |aFrame|, so we use the inline & block + // dimensions of |aFrame|. + result = ratio.ComputeRatioDependentSize( + isInlineAxis ? eLogicalAxisInline : eLogicalAxisBlock, childWM, h, + *contentBoxSizeToBoxSizingAdjust); + // We have get the inlineSizeForAspectRatio value, so we don't have to + // recompute this again below. + inlineSizeFromAspectRatio.emplace(result); + } + + if (GetDefiniteSize(styleMaxBSize, aFrame, !isInlineAxis, + aPercentageBasis, &h) || + (aPercentageBasis.isNothing() && + GetPercentBSize(styleMaxBSize, aFrame, horizontalAxis, h))) { + h = std::max(0, h - bSizeTakenByBoxSizing); + nscoord maxISize = ratio.ComputeRatioDependentSize( + isInlineAxis ? eLogicalAxisInline : eLogicalAxisBlock, childWM, h, + *contentBoxSizeToBoxSizingAdjust); + if (maxISize < result) { + result = maxISize; + } + if (maxISize < minContentSize) { + minContentSize = maxISize; + } + } + + if (GetDefiniteSize(styleMinBSize, aFrame, !isInlineAxis, + aPercentageBasis, &h) || + (aPercentageBasis.isNothing() && + GetPercentBSize(styleMinBSize, aFrame, horizontalAxis, h))) { + h = std::max(0, h - bSizeTakenByBoxSizing); + nscoord minISize = ratio.ComputeRatioDependentSize( + isInlineAxis ? eLogicalAxisInline : eLogicalAxisBlock, childWM, h, + *contentBoxSizeToBoxSizingAdjust); + if (minISize > result) { + result = minISize; + } + if (minISize > minContentSize) { + minContentSize = minISize; + } + } + + if (MOZ_UNLIKELY(aFlags & nsLayoutUtils::MIN_INTRINSIC_ISIZE) && + // FIXME: Bug 1715681. Should we use eReplacedSizing instead + // because eReplaced is set on some other frames which are + // non-replaced elements, e.g. <select>? + aFrame->IsFrameOfType(nsIFrame::eReplaced)) { + // This is the 'min-width/height:auto' "transferred size" piece of: + // https://drafts.csswg.org/css-flexbox-1/#min-size-auto + // https://drafts.csswg.org/css-grid/#min-size-auto + // Per spec, we handle it only for replaced elements. + result = std::min(result, minContentSize); + } + } + } + } + + if (aFrame->IsTableFrame()) { + // Tables can't shrink smaller than their intrinsic minimum width, + // no matter what. + min = aFrame->GetMinISize(aRenderingContext); + } + + // If we have an aspect-ratio and a definite block size of |aFrame|, we + // resolve the {min|max}-content size by the aspect-ratio and the block size. + // If |aAxis| is not the inline axis of |aFrame|, {min|max}-content should + // behaves as auto, so we don't need this. + // + // FIXME(emilio): For -moz-available it seems we shouldn't need this. + // + // https://github.com/w3c/csswg-drafts/issues/5032 + // FIXME: Bug 1670151: Use GetAspectRatio() to cover replaced elements (and + // then we can drop the check of eSupportsAspectRatio). + const AspectRatio ar = stylePos->mAspectRatio.ToLayoutRatio(); + if (isInlineAxis && ar && nsIFrame::ToExtremumLength(styleISize) && + aFrame->IsFrameOfType(nsIFrame::eSupportsAspectRatio) && + !inlineSizeFromAspectRatio) { + // This 'B' in |styleBSize| means the block size of |aFrame|. We go into + // this branch only if |aAxis| is the inline axis of |aFrame|. + const StyleSize& styleBSize = + horizontalAxis ? stylePos->mHeight : stylePos->mWidth; + nscoord bSize; + if (GetDefiniteSize(styleBSize, aFrame, !isInlineAxis, aPercentageBasis, + &bSize) || + (aPercentageBasis.isNothing() && + GetPercentBSize(styleBSize, aFrame, horizontalAxis, bSize))) { + // We cannot reuse |boxSizing| because it may be updated to content-box + // in the above if-branch. + const StyleBoxSizing boxSizingForAR = stylePos->mBoxSizing; + if (!contentBoxSizeToBoxSizingAdjust) { + contentBoxSizeToBoxSizingAdjust.emplace( + getContentBoxSizeToBoxSizingAdjust(boxSizingForAR)); + } + nscoord bSizeTakenByBoxSizing = + GetDefiniteSizeTakenByBoxSizing(boxSizingForAR, aFrame, !isInlineAxis, + ignorePadding, aPercentageBasis); + bSize -= bSizeTakenByBoxSizing; + inlineSizeFromAspectRatio.emplace(ar.ComputeRatioDependentSize( + LogicalAxis::eLogicalAxisInline, childWM, bSize, + *contentBoxSizeToBoxSizingAdjust)); + } + } + + nscoord contentBoxSize = result; + result = AddIntrinsicSizeOffset( + aRenderingContext, aFrame, offsets, aType, boxSizing, result, min, + styleISize, haveFixedMinISize ? &minISize : nullptr, styleMinISize, + haveFixedMaxISize ? &maxISize : nullptr, styleMaxISize, + inlineSizeFromAspectRatio, aFlags, aAxis); + nscoord overflow = result - aMarginBoxMinSizeClamp; + if (MOZ_UNLIKELY(overflow > 0)) { + nscoord newContentBoxSize = std::max(nscoord(0), contentBoxSize - overflow); + result -= contentBoxSize - newContentBoxSize; + } + +#ifdef DEBUG_INTRINSIC_WIDTH + nsIFrame::IndentBy(stderr, gNoiseIndent); + aFrame->ListTag(stderr); + printf_stderr(" %s %s intrinsic size for container is %d twips.\n", + aType == IntrinsicISizeType::MinISize ? "min" : "pref", + horizontalAxis ? "horizontal" : "vertical", result); +#endif + + return result; +} + +/* static */ +nscoord nsLayoutUtils::IntrinsicForContainer(gfxContext* aRenderingContext, + nsIFrame* aFrame, + IntrinsicISizeType aType, + uint32_t aFlags) { + MOZ_ASSERT(aFrame && aFrame->GetParent()); + // We want the size aFrame will contribute to its parent's inline-size. + PhysicalAxis axis = + aFrame->GetParent()->GetWritingMode().PhysicalAxis(eLogicalAxisInline); + return IntrinsicForAxis(axis, aRenderingContext, aFrame, aType, Nothing(), + aFlags); +} + +/* static */ +nscoord nsLayoutUtils::MinSizeContributionForAxis( + PhysicalAxis aAxis, gfxContext* aRC, nsIFrame* aFrame, + IntrinsicISizeType aType, const LogicalSize& aPercentageBasis, + uint32_t aFlags) { + MOZ_ASSERT(aFrame); + MOZ_ASSERT(aFrame->IsFlexOrGridItem(), + "only grid/flex items have this behavior currently"); + +#ifdef DEBUG_INTRINSIC_WIDTH + nsIFrame::IndentBy(stderr, gNoiseIndent); + aFrame->ListTag(stderr); + printf_stderr(" %s min-isize for %s WM:\n", + aType == IntrinsicISizeType::MinISize ? "min" : "pref", + aAxis == eAxisVertical ? "vertical" : "horizontal"); +#endif + + // Note: this method is only meant for grid/flex items. + const nsStylePosition* const stylePos = aFrame->StylePosition(); + StyleSize size = + aAxis == eAxisHorizontal ? stylePos->mMinWidth : stylePos->mMinHeight; + StyleMaxSize maxSize = + aAxis == eAxisHorizontal ? stylePos->mMaxWidth : stylePos->mMaxHeight; + auto childWM = aFrame->GetWritingMode(); + PhysicalAxis ourInlineAxis = childWM.PhysicalAxis(eLogicalAxisInline); + // According to the spec, max-content and min-content should behave as the + // property's initial values in block axis. + // It also make senses to use the initial values for -moz-fit-content and + // -moz-available for intrinsic size in block axis. Therefore, we reset them + // if needed. + if (aAxis != ourInlineAxis) { + if (size.BehavesLikeInitialValueOnBlockAxis()) { + size = StyleSize::Auto(); + } + if (maxSize.BehavesLikeInitialValueOnBlockAxis()) { + maxSize = StyleMaxSize::None(); + } + } + + nscoord minSize; + nscoord* fixedMinSize = nullptr; + if (size.IsAuto()) { + if (aFrame->StyleDisplay()->mOverflowX == StyleOverflow::Visible) { + size = aAxis == eAxisHorizontal ? stylePos->mWidth : stylePos->mHeight; + // This is same as above: keywords should behaves as property's initial + // values in block axis. + if (aAxis != ourInlineAxis && size.BehavesLikeInitialValueOnBlockAxis()) { + size = StyleSize::Auto(); + } + + if (GetAbsoluteCoord(size, minSize)) { + // We have a definite width/height. This is the "specified size" in: + // https://drafts.csswg.org/css-grid/#min-size-auto + fixedMinSize = &minSize; + } else if (aFrame->IsPercentageResolvedAgainstZero(size, maxSize)) { + // XXX bug 1463700: this doesn't handle calc() according to spec + minSize = 0; + fixedMinSize = &minSize; + } + // fall through - the caller will have to deal with "transferred size" + } else { + // min-[width|height]:auto with overflow != visible computes to zero. + minSize = 0; + fixedMinSize = &minSize; + } + } else if (GetAbsoluteCoord(size, minSize)) { + fixedMinSize = &minSize; + } else if (size.IsLengthPercentage()) { + MOZ_ASSERT(size.HasPercent()); + minSize = 0; + fixedMinSize = &minSize; + } + + if (!fixedMinSize) { + // Let the caller deal with the "content size" cases. +#ifdef DEBUG_INTRINSIC_WIDTH + nsIFrame::IndentBy(stderr, gNoiseIndent); + aFrame->ListTag(stderr); + printf_stderr(" %s min-isize is indefinite.\n", + aType == IntrinsicISizeType::MinISize ? "min" : "pref"); +#endif + return NS_UNCONSTRAINEDSIZE; + } + + // If aFrame is a container for font size inflation, then shrink + // wrapping inside of it should not apply font size inflation. + AutoMaybeDisableFontInflation an(aFrame); + + // The padding/margin percentage basis is the inline-size in the parent's + // writing-mode. + nscoord pmPercentageBasis = + aFrame->GetParent()->GetWritingMode().IsOrthogonalTo(childWM) + ? aPercentageBasis.BSize(childWM) + : aPercentageBasis.ISize(childWM); + nsIFrame::IntrinsicSizeOffsetData offsets = + ourInlineAxis == aAxis ? aFrame->IntrinsicISizeOffsets(pmPercentageBasis) + : aFrame->IntrinsicBSizeOffsets(pmPercentageBasis); + nscoord result = 0; + nscoord min = 0; + // Note: aInlineSizeFromAspectRatio is Nothing() here because we don't handle + // "content size" cases here (i.e. |fixedMinSize| is false here). + result = AddIntrinsicSizeOffset( + aRC, aFrame, offsets, aType, stylePos->mBoxSizing, result, min, size, + fixedMinSize, size, nullptr, maxSize, Nothing(), aFlags, aAxis); + +#ifdef DEBUG_INTRINSIC_WIDTH + nsIFrame::IndentBy(stderr, gNoiseIndent); + aFrame->ListTag(stderr); + printf_stderr(" %s min-isize is %d twips.\n", + aType == IntrinsicISizeType::MinISize ? "min" : "pref", result); +#endif + + return result; +} + +/* static */ +nscoord nsLayoutUtils::ComputeBSizeDependentValue( + nscoord aContainingBlockBSize, const LengthPercentageOrAuto& aCoord) { + // XXXldb Some callers explicitly check aContainingBlockBSize + // against NS_UNCONSTRAINEDSIZE *and* unit against eStyleUnit_Percent or + // calc()s containing percents before calling this function. + // However, it would be much more likely to catch problems without + // the unit conditions. + // XXXldb Many callers pass a non-'auto' containing block height when + // according to CSS2.1 they should be passing 'auto'. + MOZ_ASSERT( + NS_UNCONSTRAINEDSIZE != aContainingBlockBSize || !aCoord.HasPercent(), + "unexpected containing block block-size"); + + if (aCoord.IsAuto()) { + return 0; + } + + return aCoord.AsLengthPercentage().Resolve(aContainingBlockBSize); +} + +/* static */ +void nsLayoutUtils::MarkDescendantsDirty(nsIFrame* aSubtreeRoot) { + AutoTArray<nsIFrame*, 4> subtrees; + subtrees.AppendElement(aSubtreeRoot); + + // dirty descendants, iterating over subtrees that may include + // additional subtrees associated with placeholders + do { + nsIFrame* subtreeRoot = subtrees.PopLastElement(); + + // Mark all descendants dirty (using an nsTArray stack rather than + // recursion). + // Note that ReflowInput::InitResizeFlags has some similar + // code; see comments there for how and why it differs. + AutoTArray<nsIFrame*, 32> stack; + stack.AppendElement(subtreeRoot); + + do { + nsIFrame* f = stack.PopLastElement(); + + f->MarkIntrinsicISizesDirty(); + + if (f->IsPlaceholderFrame()) { + nsIFrame* oof = nsPlaceholderFrame::GetRealFrameForPlaceholder(f); + if (!nsLayoutUtils::IsProperAncestorFrame(subtreeRoot, oof)) { + // We have another distinct subtree we need to mark. + subtrees.AppendElement(oof); + } + } + + for (const auto& childList : f->ChildLists()) { + for (nsIFrame* kid : childList.mList) { + stack.AppendElement(kid); + } + } + } while (stack.Length() != 0); + } while (subtrees.Length() != 0); +} + +/* static */ +void nsLayoutUtils::MarkIntrinsicISizesDirtyIfDependentOnBSize( + nsIFrame* aFrame) { + AutoTArray<nsIFrame*, 32> stack; + stack.AppendElement(aFrame); + + do { + nsIFrame* f = stack.PopLastElement(); + + if (!f->HasAnyStateBits( + NS_FRAME_DESCENDANT_INTRINSIC_ISIZE_DEPENDS_ON_BSIZE)) { + continue; + } + f->MarkIntrinsicISizesDirty(); + + for (const auto& childList : f->ChildLists()) { + for (nsIFrame* kid : childList.mList) { + stack.AppendElement(kid); + } + } + } while (stack.Length() != 0); +} + +nsSize nsLayoutUtils::ComputeAutoSizeWithIntrinsicDimensions( + nscoord minWidth, nscoord minHeight, nscoord maxWidth, nscoord maxHeight, + nscoord tentWidth, nscoord tentHeight) { + // Now apply min/max-width/height - CSS 2.1 sections 10.4 and 10.7: + + if (minWidth > maxWidth) maxWidth = minWidth; + if (minHeight > maxHeight) maxHeight = minHeight; + + nscoord heightAtMaxWidth, heightAtMinWidth, widthAtMaxHeight, + widthAtMinHeight; + + if (tentWidth > 0) { + heightAtMaxWidth = NSCoordMulDiv(maxWidth, tentHeight, tentWidth); + if (heightAtMaxWidth < minHeight) heightAtMaxWidth = minHeight; + heightAtMinWidth = NSCoordMulDiv(minWidth, tentHeight, tentWidth); + if (heightAtMinWidth > maxHeight) heightAtMinWidth = maxHeight; + } else { + heightAtMaxWidth = heightAtMinWidth = + NS_CSS_MINMAX(tentHeight, minHeight, maxHeight); + } + + if (tentHeight > 0) { + widthAtMaxHeight = NSCoordMulDiv(maxHeight, tentWidth, tentHeight); + if (widthAtMaxHeight < minWidth) widthAtMaxHeight = minWidth; + widthAtMinHeight = NSCoordMulDiv(minHeight, tentWidth, tentHeight); + if (widthAtMinHeight > maxWidth) widthAtMinHeight = maxWidth; + } else { + widthAtMaxHeight = widthAtMinHeight = + NS_CSS_MINMAX(tentWidth, minWidth, maxWidth); + } + + // The table at http://www.w3.org/TR/CSS21/visudet.html#min-max-widths : + + nscoord width, height; + + if (tentWidth > maxWidth) { + if (tentHeight > maxHeight) { + if (int64_t(maxWidth) * int64_t(tentHeight) <= + int64_t(maxHeight) * int64_t(tentWidth)) { + width = maxWidth; + height = heightAtMaxWidth; + } else { + width = widthAtMaxHeight; + height = maxHeight; + } + } else { + // This also covers "(w > max-width) and (h < min-height)" since in + // that case (max-width/w < 1), and with (h < min-height): + // max(max-width * h/w, min-height) == min-height + width = maxWidth; + height = heightAtMaxWidth; + } + } else if (tentWidth < minWidth) { + if (tentHeight < minHeight) { + if (int64_t(minWidth) * int64_t(tentHeight) <= + int64_t(minHeight) * int64_t(tentWidth)) { + width = widthAtMinHeight; + height = minHeight; + } else { + width = minWidth; + height = heightAtMinWidth; + } + } else { + // This also covers "(w < min-width) and (h > max-height)" since in + // that case (min-width/w > 1), and with (h > max-height): + // min(min-width * h/w, max-height) == max-height + width = minWidth; + height = heightAtMinWidth; + } + } else { + if (tentHeight > maxHeight) { + width = widthAtMaxHeight; + height = maxHeight; + } else if (tentHeight < minHeight) { + width = widthAtMinHeight; + height = minHeight; + } else { + width = tentWidth; + height = tentHeight; + } + } + + return nsSize(width, height); +} + +/* static */ +nscoord nsLayoutUtils::MinISizeFromInline(nsIFrame* aFrame, + gfxContext* aRenderingContext) { + NS_ASSERTION(!aFrame->IsContainerForFontSizeInflation(), + "should not be container for font size inflation"); + + nsIFrame::InlineMinISizeData data; + DISPLAY_MIN_INLINE_SIZE(aFrame, data.mPrevLines); + aFrame->AddInlineMinISize(aRenderingContext, &data); + data.ForceBreak(); + return data.mPrevLines; +} + +/* static */ +nscoord nsLayoutUtils::PrefISizeFromInline(nsIFrame* aFrame, + gfxContext* aRenderingContext) { + NS_ASSERTION(!aFrame->IsContainerForFontSizeInflation(), + "should not be container for font size inflation"); + + nsIFrame::InlinePrefISizeData data; + DISPLAY_PREF_INLINE_SIZE(aFrame, data.mPrevLines); + aFrame->AddInlinePrefISize(aRenderingContext, &data); + data.ForceBreak(); + return data.mPrevLines; +} + +static nscolor DarkenColor(nscolor aColor) { + uint16_t hue, sat, value; + uint8_t alpha; + + // convert the RBG to HSV so we can get the lightness (which is the v) + NS_RGB2HSV(aColor, hue, sat, value, alpha); + + // The goal here is to send white to black while letting colored + // stuff stay colored... So we adopt the following approach. + // Something with sat = 0 should end up with value = 0. Something + // with a high sat can end up with a high value and it's ok.... At + // the same time, we don't want to make things lighter. Do + // something simple, since it seems to work. + if (value > sat) { + value = sat; + // convert this color back into the RGB color space. + NS_HSV2RGB(aColor, hue, sat, value, alpha); + } + return aColor; +} + +// Check whether we should darken text/decoration colors. We need to do this if +// background images and colors are being suppressed, because that means +// light text will not be visible against the (presumed light-colored) +// background. +static bool ShouldDarkenColors(nsIFrame* aFrame) { + nsPresContext* pc = aFrame->PresContext(); + if (pc->GetBackgroundColorDraw() || pc->GetBackgroundImageDraw()) { + return false; + } + return aFrame->StyleVisibility()->mPrintColorAdjust != + StylePrintColorAdjust::Exact; +} + +nscolor nsLayoutUtils::DarkenColorIfNeeded(nsIFrame* aFrame, nscolor aColor) { + return ShouldDarkenColors(aFrame) ? DarkenColor(aColor) : aColor; +} + +gfxFloat nsLayoutUtils::GetSnappedBaselineY(nsIFrame* aFrame, + gfxContext* aContext, nscoord aY, + nscoord aAscent) { + gfxFloat appUnitsPerDevUnit = aFrame->PresContext()->AppUnitsPerDevPixel(); + gfxFloat baseline = gfxFloat(aY) + aAscent; + gfxRect putativeRect(0, baseline / appUnitsPerDevUnit, 1, 1); + if (!aContext->UserToDevicePixelSnapped( + putativeRect, gfxContext::SnapOption::IgnoreScale)) { + return baseline; + } + return aContext->DeviceToUser(putativeRect.TopLeft()).y * appUnitsPerDevUnit; +} + +gfxFloat nsLayoutUtils::GetSnappedBaselineX(nsIFrame* aFrame, + gfxContext* aContext, nscoord aX, + nscoord aAscent) { + gfxFloat appUnitsPerDevUnit = aFrame->PresContext()->AppUnitsPerDevPixel(); + gfxFloat baseline = gfxFloat(aX) + aAscent; + gfxRect putativeRect(baseline / appUnitsPerDevUnit, 0, 1, 1); + if (!aContext->UserToDevicePixelSnapped( + putativeRect, gfxContext::SnapOption::IgnoreScale)) { + return baseline; + } + return aContext->DeviceToUser(putativeRect.TopLeft()).x * appUnitsPerDevUnit; +} + +// Hard limit substring lengths to 8000 characters ... this lets us statically +// size the cluster buffer array in FindSafeLength +#define MAX_GFX_TEXT_BUF_SIZE 8000 + +static int32_t FindSafeLength(const char16_t* aString, uint32_t aLength, + uint32_t aMaxChunkLength) { + if (aLength <= aMaxChunkLength) return aLength; + + int32_t len = aMaxChunkLength; + + // Ensure that we don't break inside a surrogate pair + while (len > 0 && NS_IS_LOW_SURROGATE(aString[len])) { + len--; + } + if (len == 0) { + // We don't want our caller to go into an infinite loop, so don't + // return zero. It's hard to imagine how we could actually get here + // unless there are languages that allow clusters of arbitrary size. + // If there are and someone feeds us a 500+ character cluster, too + // bad. + return aMaxChunkLength; + } + return len; +} + +static int32_t GetMaxChunkLength(nsFontMetrics& aFontMetrics) { + return std::min(aFontMetrics.GetMaxStringLength(), MAX_GFX_TEXT_BUF_SIZE); +} + +nscoord nsLayoutUtils::AppUnitWidthOfString(const char16_t* aString, + uint32_t aLength, + nsFontMetrics& aFontMetrics, + DrawTarget* aDrawTarget) { + uint32_t maxChunkLength = GetMaxChunkLength(aFontMetrics); + nscoord width = 0; + while (aLength > 0) { + int32_t len = FindSafeLength(aString, aLength, maxChunkLength); + width += aFontMetrics.GetWidth(aString, len, aDrawTarget); + aLength -= len; + aString += len; + } + return width; +} + +nscoord nsLayoutUtils::AppUnitWidthOfStringBidi(const char16_t* aString, + uint32_t aLength, + const nsIFrame* aFrame, + nsFontMetrics& aFontMetrics, + gfxContext& aContext) { + nsPresContext* presContext = aFrame->PresContext(); + if (presContext->BidiEnabled()) { + mozilla::intl::BidiEmbeddingLevel level = + nsBidiPresUtils::BidiLevelFromStyle(aFrame->Style()); + return nsBidiPresUtils::MeasureTextWidth( + aString, aLength, level, presContext, aContext, aFontMetrics); + } + aFontMetrics.SetTextRunRTL(false); + aFontMetrics.SetVertical(aFrame->GetWritingMode().IsVertical()); + aFontMetrics.SetTextOrientation(aFrame->StyleVisibility()->mTextOrientation); + return nsLayoutUtils::AppUnitWidthOfString(aString, aLength, aFontMetrics, + aContext.GetDrawTarget()); +} + +bool nsLayoutUtils::StringWidthIsGreaterThan(const nsString& aString, + nsFontMetrics& aFontMetrics, + DrawTarget* aDrawTarget, + nscoord aWidth) { + const char16_t* string = aString.get(); + uint32_t length = aString.Length(); + uint32_t maxChunkLength = GetMaxChunkLength(aFontMetrics); + nscoord width = 0; + while (length > 0) { + int32_t len = FindSafeLength(string, length, maxChunkLength); + width += aFontMetrics.GetWidth(string, len, aDrawTarget); + if (width > aWidth) { + return true; + } + length -= len; + string += len; + } + return false; +} + +nsBoundingMetrics nsLayoutUtils::AppUnitBoundsOfString( + const char16_t* aString, uint32_t aLength, nsFontMetrics& aFontMetrics, + DrawTarget* aDrawTarget) { + uint32_t maxChunkLength = GetMaxChunkLength(aFontMetrics); + int32_t len = FindSafeLength(aString, aLength, maxChunkLength); + // Assign directly in the first iteration. This ensures that + // negative ascent/descent can be returned and the left bearing + // is properly initialized. + nsBoundingMetrics totalMetrics = + aFontMetrics.GetBoundingMetrics(aString, len, aDrawTarget); + aLength -= len; + aString += len; + + while (aLength > 0) { + len = FindSafeLength(aString, aLength, maxChunkLength); + nsBoundingMetrics metrics = + aFontMetrics.GetBoundingMetrics(aString, len, aDrawTarget); + totalMetrics += metrics; + aLength -= len; + aString += len; + } + return totalMetrics; +} + +void nsLayoutUtils::DrawString(const nsIFrame* aFrame, + nsFontMetrics& aFontMetrics, + gfxContext* aContext, const char16_t* aString, + int32_t aLength, nsPoint aPoint, + ComputedStyle* aComputedStyle, + DrawStringFlags aFlags) { + nsresult rv = NS_ERROR_FAILURE; + + // If caller didn't pass a style, use the frame's. + if (!aComputedStyle) { + aComputedStyle = aFrame->Style(); + } + + if (aFlags & DrawStringFlags::ForceHorizontal) { + aFontMetrics.SetVertical(false); + } else { + aFontMetrics.SetVertical(WritingMode(aComputedStyle).IsVertical()); + } + + aFontMetrics.SetTextOrientation( + aComputedStyle->StyleVisibility()->mTextOrientation); + + nsPresContext* presContext = aFrame->PresContext(); + if (presContext->BidiEnabled()) { + mozilla::intl::BidiEmbeddingLevel level = + nsBidiPresUtils::BidiLevelFromStyle(aComputedStyle); + rv = nsBidiPresUtils::RenderText(aString, aLength, level, presContext, + *aContext, aContext->GetDrawTarget(), + aFontMetrics, aPoint.x, aPoint.y); + } + if (NS_FAILED(rv)) { + aFontMetrics.SetTextRunRTL(false); + DrawUniDirString(aString, aLength, aPoint, aFontMetrics, *aContext); + } +} + +void nsLayoutUtils::DrawUniDirString(const char16_t* aString, uint32_t aLength, + const nsPoint& aPoint, + nsFontMetrics& aFontMetrics, + gfxContext& aContext) { + nscoord x = aPoint.x; + nscoord y = aPoint.y; + + uint32_t maxChunkLength = GetMaxChunkLength(aFontMetrics); + if (aLength <= maxChunkLength) { + aFontMetrics.DrawString(aString, aLength, x, y, &aContext, + aContext.GetDrawTarget()); + return; + } + + bool isRTL = aFontMetrics.GetTextRunRTL(); + + // If we're drawing right to left, we must start at the end. + if (isRTL) { + x += nsLayoutUtils::AppUnitWidthOfString(aString, aLength, aFontMetrics, + aContext.GetDrawTarget()); + } + + while (aLength > 0) { + int32_t len = FindSafeLength(aString, aLength, maxChunkLength); + nscoord width = + aFontMetrics.GetWidth(aString, len, aContext.GetDrawTarget()); + if (isRTL) { + x -= width; + } + aFontMetrics.DrawString(aString, len, x, y, &aContext, + aContext.GetDrawTarget()); + if (!isRTL) { + x += width; + } + aLength -= len; + aString += len; + } +} + +/* static */ +void nsLayoutUtils::PaintTextShadow( + const nsIFrame* aFrame, gfxContext* aContext, const nsRect& aTextRect, + const nsRect& aDirtyRect, const nscolor& aForegroundColor, + TextShadowCallback aCallback, void* aCallbackData) { + const nsStyleText* textStyle = aFrame->StyleText(); + auto shadows = textStyle->mTextShadow.AsSpan(); + if (shadows.IsEmpty()) { + return; + } + + // Text shadow happens with the last value being painted at the back, + // ie. it is painted first. + gfxContext* aDestCtx = aContext; + for (auto& shadow : Reversed(shadows)) { + nsPoint shadowOffset(shadow.horizontal.ToAppUnits(), + shadow.vertical.ToAppUnits()); + nscoord blurRadius = std::max(shadow.blur.ToAppUnits(), 0); + + nsRect shadowRect(aTextRect); + shadowRect.MoveBy(shadowOffset); + + nsPresContext* presCtx = aFrame->PresContext(); + nsContextBoxBlur contextBoxBlur; + + nscolor shadowColor = shadow.color.CalcColor(aForegroundColor); + + // Webrender just needs the shadow details + if (auto* textDrawer = aContext->GetTextDrawer()) { + wr::Shadow wrShadow; + + wrShadow.offset = { + presCtx->AppUnitsToFloatDevPixels(shadow.horizontal.ToAppUnits()), + presCtx->AppUnitsToFloatDevPixels(shadow.vertical.ToAppUnits())}; + + wrShadow.blur_radius = presCtx->AppUnitsToFloatDevPixels(blurRadius); + wrShadow.color = wr::ToColorF(ToDeviceColor(shadowColor)); + + // Gecko already inflates the bounding rect of text shadows, + // so tell WR not to inflate again. + bool inflate = false; + textDrawer->AppendShadow(wrShadow, inflate); + continue; + } + + gfxContext* shadowContext = contextBoxBlur.Init( + shadowRect, 0, blurRadius, presCtx->AppUnitsPerDevPixel(), aDestCtx, + aDirtyRect, nullptr, + nsContextBoxBlur::DISABLE_HARDWARE_ACCELERATION_BLUR); + if (!shadowContext) continue; + + aDestCtx->Save(); + aDestCtx->NewPath(); + aDestCtx->SetColor(sRGBColor::FromABGR(shadowColor)); + + // The callback will draw whatever we want to blur as a shadow. + aCallback(shadowContext, shadowOffset, shadowColor, aCallbackData); + + contextBoxBlur.DoPaint(); + aDestCtx->Restore(); + } +} + +/* static */ +nscoord nsLayoutUtils::GetCenteredFontBaseline(nsFontMetrics* aFontMetrics, + nscoord aLineHeight, + bool aIsInverted) { + nscoord fontAscent = + aIsInverted ? aFontMetrics->MaxDescent() : aFontMetrics->MaxAscent(); + nscoord fontHeight = aFontMetrics->MaxHeight(); + + nscoord leading = aLineHeight - fontHeight; + return fontAscent + leading / 2; +} + +/* static */ +bool nsLayoutUtils::GetFirstLineBaseline(WritingMode aWritingMode, + const nsIFrame* aFrame, + nscoord* aResult) { + LinePosition position; + if (!GetFirstLinePosition(aWritingMode, aFrame, &position)) return false; + *aResult = position.mBaseline; + return true; +} + +/* static */ +bool nsLayoutUtils::GetFirstLinePosition(WritingMode aWM, + const nsIFrame* aFrame, + LinePosition* aResult) { + if (aFrame->StyleDisplay()->IsContainLayout()) { + return false; + } + const nsBlockFrame* block = do_QueryFrame(aFrame); + if (!block) { + // For the first-line baseline we also have to check for a table, and if + // so, use the baseline of its first row. + LayoutFrameType fType = aFrame->Type(); + if (fType == LayoutFrameType::TableWrapper || + fType == LayoutFrameType::FlexContainer || + fType == LayoutFrameType::GridContainer) { + if ((fType == LayoutFrameType::GridContainer && + aFrame->HasAnyStateBits(NS_STATE_GRID_SYNTHESIZE_BASELINE)) || + (fType == LayoutFrameType::FlexContainer && + aFrame->HasAnyStateBits(NS_STATE_FLEX_SYNTHESIZE_BASELINE)) || + (fType == LayoutFrameType::TableWrapper && + static_cast<const nsTableWrapperFrame*>(aFrame)->GetRowCount() == + 0)) { + // empty grid/flex/table container + aResult->mBStart = 0; + aResult->mBaseline = aFrame->SynthesizeBaselineBOffsetFromBorderBox( + aWM, BaselineSharingGroup::First); + aResult->mBEnd = aFrame->BSize(aWM); + return true; + } + if (fType == LayoutFrameType::TableWrapper && + aFrame->GetWritingMode().IsOrthogonalTo(aWM)) { + // For tables, the upcoming GetLogicalBaseline call would determine the + // table's baseline from its first row that has a baseline. However: + // this doesn't make sense for an orthogonal writing mode, so in that + // case we report no baseline instead. The table wrapper and its rows + // should flow the same way, so we can bail out early, but this logic + // wouldn't be correct to transplant into other places in the codebase + // (Depending on how bug 1786633 is resolved). + return false; + } + aResult->mBStart = 0; + aResult->mBaseline = aFrame->GetLogicalBaseline(aWM); + // This is what we want for the list bullet caller; not sure if + // other future callers will want the same. + aResult->mBEnd = aFrame->BSize(aWM); + return true; + } + + // For first-line baselines, we have to consider scroll frames. + if (nsIScrollableFrame* sFrame = + do_QueryFrame(const_cast<nsIFrame*>(aFrame))) { + LinePosition kidPosition; + if (GetFirstLinePosition(aWM, sFrame->GetScrolledFrame(), &kidPosition)) { + // Consider only the border (Padding is ignored, since + // `-moz-scrolled-content` inherits and handles the padding) that + // contributes to the kid's position, not the scrolling, so we get the + // initial position. + *aResult = kidPosition + aFrame->GetLogicalUsedBorder(aWM).BStart(aWM); + // Don't want to move the line's block positioning, but the baseline + // needs to be clamped (See bug 1791069). + aResult->mBaseline = std::clamp(aResult->mBaseline, 0, + aFrame->GetLogicalSize(aWM).BSize(aWM)); + return true; + } + return false; + } + + if (fType == LayoutFrameType::FieldSet || + fType == LayoutFrameType::ColumnSet) { + LinePosition kidPosition; + nsIFrame* kid = aFrame->PrincipalChildList().FirstChild(); + // If aFrame is fieldset, kid might be a legend frame here, but that's ok. + if (kid && GetFirstLinePosition(aWM, kid, &kidPosition)) { + *aResult = kidPosition + + kid->GetLogicalNormalPosition(aWM, aFrame->GetSize()).B(aWM); + return true; + } + return false; + } + + // No baseline. + return false; + } + + for (const auto& line : block->Lines()) { + if (line.IsBlock()) { + const nsIFrame* kid = line.mFirstChild; + LinePosition kidPosition; + if (GetFirstLinePosition(aWM, kid, &kidPosition)) { + // XXX Not sure if this is the correct value to use for container + // width here. It will only be used in vertical-rl layout, + // which we don't have full support and testing for yet. + const auto& containerSize = line.mContainerSize; + *aResult = kidPosition + + kid->GetLogicalNormalPosition(aWM, containerSize).B(aWM); + return true; + } + } else { + // XXX Is this the right test? We have some bogus empty lines + // floating around, but IsEmpty is perhaps too weak. + if (0 != line.BSize() || !line.IsEmpty()) { + nscoord bStart = line.BStart(); + aResult->mBStart = bStart; + aResult->mBaseline = bStart + line.GetLogicalAscent(); + aResult->mBEnd = bStart + line.BSize(); + return true; + } + } + } + return false; +} + +/* static */ +bool nsLayoutUtils::GetLastLineBaseline(WritingMode aWM, const nsIFrame* aFrame, + nscoord* aResult) { + if (aFrame->StyleDisplay()->IsContainLayout()) { + return false; + } + + const nsBlockFrame* block = do_QueryFrame(aFrame); + if (!block) { + if (nsIScrollableFrame* sFrame = do_QueryFrame(aFrame)) { + // Use the baseline position only if the last line's baseline is within + // the scrolling frame's box in the initial position. + const auto* scrolledFrame = sFrame->GetScrolledFrame(); + if (!GetLastLineBaseline(aWM, scrolledFrame, aResult)) { + return false; + } + // Go from scrolled frame to scrollable frame position. + *aResult += aFrame->GetLogicalUsedBorder(aWM).BStart(aWM); + const auto maxBaseline = aFrame->GetLogicalSize(aWM).BSize(aWM); + // Clamp the last baseline to border (See bug 1791069). + *aResult = std::clamp(*aResult, 0, maxBaseline); + return true; + } + // No baseline. + return false; + } + + for (nsBlockFrame::ConstReverseLineIterator line = block->LinesRBegin(), + line_end = block->LinesREnd(); + line != line_end; ++line) { + if (line->IsBlock()) { + nsIFrame* kid = line->mFirstChild; + nscoord kidBaseline; + const nsSize& containerSize = line->mContainerSize; + if (GetLastLineBaseline(aWM, kid, &kidBaseline)) { + // Ignore relative positioning for baseline calculations + *aResult = kidBaseline + + kid->GetLogicalNormalPosition(aWM, containerSize).B(aWM); + return true; + } + if (kid->IsScrollFrame()) { + // Defer to nsIFrame::GetLogicalBaseline (which synthesizes a baseline + // from the margin-box). + kidBaseline = kid->GetLogicalBaseline(aWM); + *aResult = kidBaseline + + kid->GetLogicalNormalPosition(aWM, containerSize).B(aWM); + return true; + } + } else { + // XXX Is this the right test? We have some bogus empty lines + // floating around, but IsEmpty is perhaps too weak. + if (line->BSize() != 0 || !line->IsEmpty()) { + *aResult = line->BStart() + line->GetLogicalAscent(); + return true; + } + } + } + return false; +} + +static nscoord CalculateBlockContentBEnd(WritingMode aWM, + nsBlockFrame* aFrame) { + MOZ_ASSERT(aFrame, "null ptr"); + + nscoord contentBEnd = 0; + + for (const auto& line : aFrame->Lines()) { + if (line.IsBlock()) { + nsIFrame* child = line.mFirstChild; + const auto& containerSize = line.mContainerSize; + nscoord offset = + child->GetLogicalNormalPosition(aWM, containerSize).B(aWM); + contentBEnd = + std::max(contentBEnd, + nsLayoutUtils::CalculateContentBEnd(aWM, child) + offset); + } else { + contentBEnd = std::max(contentBEnd, line.BEnd()); + } + } + return contentBEnd; +} + +/* static */ +nscoord nsLayoutUtils::CalculateContentBEnd(WritingMode aWM, nsIFrame* aFrame) { + MOZ_ASSERT(aFrame, "null ptr"); + + nscoord contentBEnd = aFrame->BSize(aWM); + + // We want scrollable overflow rather than visual because this + // calculation is intended to affect layout. + LogicalSize overflowSize(aWM, aFrame->ScrollableOverflowRect().Size()); + if (overflowSize.BSize(aWM) > contentBEnd) { + FrameChildListIDs skip = {FrameChildListID::Overflow, + FrameChildListID::ExcessOverflowContainers, + FrameChildListID::OverflowOutOfFlow}; + nsBlockFrame* blockFrame = do_QueryFrame(aFrame); + if (blockFrame) { + contentBEnd = + std::max(contentBEnd, CalculateBlockContentBEnd(aWM, blockFrame)); + skip += FrameChildListID::Principal; + } + for (const auto& [list, listID] : aFrame->ChildLists()) { + if (!skip.contains(listID)) { + for (nsIFrame* child : list) { + nscoord offset = + child->GetLogicalNormalPosition(aWM, aFrame->GetSize()).B(aWM); + contentBEnd = + std::max(contentBEnd, CalculateContentBEnd(aWM, child) + offset); + } + } + } + } + return contentBEnd; +} + +/* static */ +nsIFrame* nsLayoutUtils::GetClosestLayer(nsIFrame* aFrame) { + nsIFrame* layer; + for (layer = aFrame; layer; layer = layer->GetParent()) { + if (layer->IsAbsPosContainingBlock() || + (layer->GetParent() && layer->GetParent()->IsScrollFrame())) + break; + } + if (layer) return layer; + return aFrame->PresShell()->GetRootFrame(); +} + +SamplingFilter nsLayoutUtils::GetSamplingFilterForFrame(nsIFrame* aForFrame) { + switch (aForFrame->UsedImageRendering()) { + case StyleImageRendering::Smooth: + case StyleImageRendering::Optimizequality: + return SamplingFilter::LINEAR; + case StyleImageRendering::CrispEdges: + case StyleImageRendering::Optimizespeed: + case StyleImageRendering::Pixelated: + return SamplingFilter::POINT; + case StyleImageRendering::Auto: + return SamplingFilter::GOOD; + } + MOZ_ASSERT_UNREACHABLE("Unknown image-rendering value"); + return SamplingFilter::GOOD; +} + +/** + * Given an image being drawn into an appunit coordinate system, and + * a point in that coordinate system, map the point back into image + * pixel space. + * @param aSize the size of the image, in pixels + * @param aDest the rectangle that the image is being mapped into + * @param aPt a point in the same coordinate system as the rectangle + */ +static gfxPoint MapToFloatImagePixels(const gfxSize& aSize, + const gfxRect& aDest, + const gfxPoint& aPt) { + return gfxPoint(((aPt.x - aDest.X()) * aSize.width) / aDest.Width(), + ((aPt.y - aDest.Y()) * aSize.height) / aDest.Height()); +} + +/** + * Given an image being drawn into an pixel-based coordinate system, and + * a point in image space, map the point into the pixel-based coordinate + * system. + * @param aSize the size of the image, in pixels + * @param aDest the rectangle that the image is being mapped into + * @param aPt a point in image space + */ +static gfxPoint MapToFloatUserPixels(const gfxSize& aSize, const gfxRect& aDest, + const gfxPoint& aPt) { + return gfxPoint(aPt.x * aDest.Width() / aSize.width + aDest.X(), + aPt.y * aDest.Height() / aSize.height + aDest.Y()); +} + +/* static */ +gfxRect nsLayoutUtils::RectToGfxRect(const nsRect& aRect, + int32_t aAppUnitsPerDevPixel) { + return gfxRect(gfxFloat(aRect.x) / aAppUnitsPerDevPixel, + gfxFloat(aRect.y) / aAppUnitsPerDevPixel, + gfxFloat(aRect.width) / aAppUnitsPerDevPixel, + gfxFloat(aRect.height) / aAppUnitsPerDevPixel); +} + +struct SnappedImageDrawingParameters { + // A transform from image space to device space. + gfxMatrix imageSpaceToDeviceSpace; + // The size at which the image should be drawn (which may not be its + // intrinsic size due to, for example, HQ scaling). + nsIntSize size; + // The region in tiled image space which will be drawn, with an associated + // region to which sampling should be restricted. + ImageRegion region; + // The default viewport size for SVG images, which we use unless a different + // one has been explicitly specified. This is the same as |size| except that + // it does not take into account any transformation on the gfxContext we're + // drawing to - for example, CSS transforms are not taken into account. + CSSIntSize svgViewportSize; + // Whether there's anything to draw at all. + bool shouldDraw; + + SnappedImageDrawingParameters() + : region(ImageRegion::Empty()), shouldDraw(false) {} + + SnappedImageDrawingParameters(const gfxMatrix& aImageSpaceToDeviceSpace, + const nsIntSize& aSize, + const ImageRegion& aRegion, + const CSSIntSize& aSVGViewportSize) + : imageSpaceToDeviceSpace(aImageSpaceToDeviceSpace), + size(aSize), + region(aRegion), + svgViewportSize(aSVGViewportSize), + shouldDraw(true) {} +}; + +/** + * Given two axis-aligned rectangles, returns the transformation that maps the + * first onto the second. + * + * @param aFrom The rect to be transformed. + * @param aTo The rect that aFrom should be mapped onto by the transformation. + */ +static gfxMatrix TransformBetweenRects(const gfxRect& aFrom, + const gfxRect& aTo) { + MatrixScalesDouble scale(aTo.width / aFrom.width, aTo.height / aFrom.height); + gfxPoint translation(aTo.x - aFrom.x * scale.xScale, + aTo.y - aFrom.y * scale.yScale); + return gfxMatrix(scale.xScale, 0, 0, scale.yScale, translation.x, + translation.y); +} + +static nsRect TileNearRect(const nsRect& aAnyTile, const nsRect& aTargetRect) { + nsPoint distance = aTargetRect.TopLeft() - aAnyTile.TopLeft(); + return aAnyTile + nsPoint(distance.x / aAnyTile.width * aAnyTile.width, + distance.y / aAnyTile.height * aAnyTile.height); +} + +static gfxFloat StableRound(gfxFloat aValue) { + // Values slightly less than 0.5 should round up like 0.5 would; we're + // assuming they were meant to be 0.5. + return floor(aValue + 0.5001); +} + +static gfxPoint StableRound(const gfxPoint& aPoint) { + return gfxPoint(StableRound(aPoint.x), StableRound(aPoint.y)); +} + +/** + * Given a set of input parameters, compute certain output parameters + * for drawing an image with the image snapping algorithm. + * See https://wiki.mozilla.org/Gecko:Image_Snapping_and_Rendering + * + * @see nsLayoutUtils::DrawImage() for the descriptions of input parameters + */ +static SnappedImageDrawingParameters ComputeSnappedImageDrawingParameters( + gfxContext* aCtx, int32_t aAppUnitsPerDevPixel, const nsRect aDest, + const nsRect aFill, const nsPoint aAnchor, const nsRect aDirty, + imgIContainer* aImage, const SamplingFilter aSamplingFilter, + uint32_t aImageFlags, ExtendMode aExtendMode) { + if (aDest.IsEmpty() || aFill.IsEmpty()) + return SnappedImageDrawingParameters(); + + // Avoid unnecessarily large offsets. + bool doTile = !aDest.Contains(aFill); + nsRect appUnitDest = + doTile ? TileNearRect(aDest, aFill.Intersect(aDirty)) : aDest; + nsPoint anchor = aAnchor + (appUnitDest.TopLeft() - aDest.TopLeft()); + + gfxRect devPixelDest = + nsLayoutUtils::RectToGfxRect(appUnitDest, aAppUnitsPerDevPixel); + gfxRect devPixelFill = + nsLayoutUtils::RectToGfxRect(aFill, aAppUnitsPerDevPixel); + gfxRect devPixelDirty = + nsLayoutUtils::RectToGfxRect(aDirty, aAppUnitsPerDevPixel); + + gfxMatrix currentMatrix = aCtx->CurrentMatrixDouble(); + gfxRect fill = devPixelFill; + gfxRect dest = devPixelDest; + bool didSnap; + // Snap even if we have a scale in the context. But don't snap if + // we have something that's not translation+scale, or if the scale flips in + // the X or Y direction, because snapped image drawing can't handle that yet. + if (!currentMatrix.HasNonAxisAlignedTransform() && currentMatrix._11 > 0.0 && + currentMatrix._22 > 0.0 && + aCtx->UserToDevicePixelSnapped(fill, + gfxContext::SnapOption::IgnoreScale) && + aCtx->UserToDevicePixelSnapped(dest, + gfxContext::SnapOption::IgnoreScale)) { + // We snapped. On this code path, |fill| and |dest| take into account + // currentMatrix's transform. + didSnap = true; + } else { + // We didn't snap. On this code path, |fill| and |dest| do not take into + // account currentMatrix's transform. + didSnap = false; + fill = devPixelFill; + dest = devPixelDest; + } + + // If we snapped above, |dest| already takes into account |currentMatrix|'s + // scale and has integer coordinates. If not, we need these properties to + // compute the optimal drawn image size, so compute |snappedDestSize| here. + gfxSize snappedDestSize = dest.Size(); + auto scaleFactors = currentMatrix.ScaleFactors(); + if (!didSnap) { + snappedDestSize.Scale(scaleFactors.xScale, scaleFactors.yScale); + snappedDestSize.width = NS_round(snappedDestSize.width); + snappedDestSize.height = NS_round(snappedDestSize.height); + } + + // We need to be sure that this is at least one pixel in width and height, + // or we'll end up drawing nothing even if we have a nonempty fill. + snappedDestSize.width = std::max(snappedDestSize.width, 1.0); + snappedDestSize.height = std::max(snappedDestSize.height, 1.0); + + // Bail if we're not going to end up drawing anything. + if (fill.IsEmpty()) { + return SnappedImageDrawingParameters(); + } + + nsIntSize intImageSize = aImage->OptimalImageSizeForDest( + snappedDestSize, imgIContainer::FRAME_CURRENT, aSamplingFilter, + aImageFlags); + + nsIntSize svgViewportSize; + if (scaleFactors.xScale == 1.0 && scaleFactors.yScale == 1.0) { + // intImageSize is scaled by currentMatrix. But since there are no scale + // factors in currentMatrix, it is safe to assign intImageSize to + // svgViewportSize directly. + svgViewportSize = intImageSize; + } else { + // We should not take into account any transformation of currentMatrix + // when computing svg viewport size. Since currentMatrix contains scale + // factors, we need to recompute SVG viewport by unscaled devPixelDest. + svgViewportSize = aImage->OptimalImageSizeForDest( + devPixelDest.Size(), imgIContainer::FRAME_CURRENT, aSamplingFilter, + aImageFlags); + } + + gfxSize imageSize(intImageSize.width, intImageSize.height); + + // Compute the set of pixels that would be sampled by an ideal rendering + gfxPoint subimageTopLeft = + MapToFloatImagePixels(imageSize, devPixelDest, devPixelFill.TopLeft()); + gfxPoint subimageBottomRight = MapToFloatImagePixels( + imageSize, devPixelDest, devPixelFill.BottomRight()); + gfxRect subimage; + subimage.MoveTo(NSToIntFloor(subimageTopLeft.x), + NSToIntFloor(subimageTopLeft.y)); + subimage.SizeTo(NSToIntCeil(subimageBottomRight.x) - subimage.x, + NSToIntCeil(subimageBottomRight.y) - subimage.y); + + if (subimage.IsEmpty()) { + // Bail if the subimage is empty (we're not going to be drawing anything). + return SnappedImageDrawingParameters(); + } + + gfxMatrix transform; + gfxMatrix invTransform; + + bool anchorAtUpperLeft = + anchor.x == appUnitDest.x && anchor.y == appUnitDest.y; + bool exactlyOneImageCopy = aFill.IsEqualEdges(appUnitDest); + if (anchorAtUpperLeft && exactlyOneImageCopy) { + // The simple case: we can ignore the anchor point and compute the + // transformation from the sampled region (the subimage) to the fill rect. + // This approach is preferable when it works since it tends to produce + // less numerical error. + transform = TransformBetweenRects(subimage, fill); + invTransform = TransformBetweenRects(fill, subimage); + } else { + // The more complicated case: we compute the transformation from the + // image rect positioned at the image space anchor point to the dest rect + // positioned at the device space anchor point. + + // Compute the anchor point in both device space and image space. This + // code assumes that pixel-based devices have one pixel per device unit! + gfxPoint anchorPoint(gfxFloat(anchor.x) / aAppUnitsPerDevPixel, + gfxFloat(anchor.y) / aAppUnitsPerDevPixel); + gfxPoint imageSpaceAnchorPoint = + MapToFloatImagePixels(imageSize, devPixelDest, anchorPoint); + + if (didSnap) { + imageSpaceAnchorPoint = StableRound(imageSpaceAnchorPoint); + anchorPoint = imageSpaceAnchorPoint; + anchorPoint = MapToFloatUserPixels(imageSize, devPixelDest, anchorPoint); + anchorPoint = currentMatrix.TransformPoint(anchorPoint); + anchorPoint = StableRound(anchorPoint); + } + + // Compute an unsnapped version of the dest rect's size. We continue to + // follow the pattern that we take |currentMatrix| into account only if + // |didSnap| is true. + gfxSize unsnappedDestSize = + didSnap ? devPixelDest.Size() * currentMatrix.ScaleFactors() + : devPixelDest.Size(); + + gfxRect anchoredDestRect(anchorPoint, unsnappedDestSize); + gfxRect anchoredImageRect(imageSpaceAnchorPoint, imageSize); + + // Calculate anchoredDestRect with snapped fill rect when the devPixelFill + // rect corresponds to just a single tile in that direction + if (fill.Width() != devPixelFill.Width() && + devPixelDest.x == devPixelFill.x && + devPixelDest.XMost() == devPixelFill.XMost()) { + anchoredDestRect.width = fill.width; + } + if (fill.Height() != devPixelFill.Height() && + devPixelDest.y == devPixelFill.y && + devPixelDest.YMost() == devPixelFill.YMost()) { + anchoredDestRect.height = fill.height; + } + + transform = TransformBetweenRects(anchoredImageRect, anchoredDestRect); + invTransform = TransformBetweenRects(anchoredDestRect, anchoredImageRect); + } + + // If the transform is not a straight translation by integers, then + // filtering will occur, and restricting the fill rect to the dirty rect + // would change the values computed for edge pixels, which we can't allow. + // Also, if 'didSnap' is false then rounding out 'devPixelDirty' might not + // produce pixel-aligned coordinates, which would also break the values + // computed for edge pixels. + if (didSnap && !invTransform.HasNonIntegerTranslation()) { + // This form of Transform is safe to call since non-axis-aligned + // transforms wouldn't be snapped. + devPixelDirty = currentMatrix.TransformRect(devPixelDirty); + devPixelDirty.RoundOut(); + fill = fill.Intersect(devPixelDirty); + } + if (fill.IsEmpty()) return SnappedImageDrawingParameters(); + + gfxRect imageSpaceFill(didSnap ? invTransform.TransformRect(fill) + : invTransform.TransformBounds(fill)); + + // If we didn't snap, we need to post-multiply the matrix on the context to + // get the final matrix we'll draw with, because we didn't take it into + // account when computing the matrices above. + if (!didSnap) { + transform = transform * currentMatrix; + } + + ExtendMode extendMode = (aImageFlags & imgIContainer::FLAG_CLAMP) + ? ExtendMode::CLAMP + : aExtendMode; + // We were passed in the default extend mode but need to tile. + if (extendMode == ExtendMode::CLAMP && doTile) { + MOZ_ASSERT(!(aImageFlags & imgIContainer::FLAG_CLAMP)); + extendMode = ExtendMode::REPEAT; + } + + ImageRegion region = ImageRegion::CreateWithSamplingRestriction( + imageSpaceFill, subimage, extendMode); + + return SnappedImageDrawingParameters( + transform, intImageSize, region, + CSSIntSize(svgViewportSize.width, svgViewportSize.height)); +} + +static ImgDrawResult DrawImageInternal( + gfxContext& aContext, nsPresContext* aPresContext, imgIContainer* aImage, + const SamplingFilter aSamplingFilter, const nsRect& aDest, + const nsRect& aFill, const nsPoint& aAnchor, const nsRect& aDirty, + const SVGImageContext& aSVGContext, uint32_t aImageFlags, + ExtendMode aExtendMode = ExtendMode::CLAMP, float aOpacity = 1.0) { + ImgDrawResult result = ImgDrawResult::SUCCESS; + + aImageFlags |= imgIContainer::FLAG_ASYNC_NOTIFY; + + if (aPresContext->Type() == nsPresContext::eContext_Print) { + // We want vector images to be passed on as vector commands, not a raster + // image. + aImageFlags |= imgIContainer::FLAG_BYPASS_SURFACE_CACHE; + } + if (aDest.Contains(aFill)) { + aImageFlags |= imgIContainer::FLAG_CLAMP; + } + int32_t appUnitsPerDevPixel = aPresContext->AppUnitsPerDevPixel(); + + SnappedImageDrawingParameters params = ComputeSnappedImageDrawingParameters( + &aContext, appUnitsPerDevPixel, aDest, aFill, aAnchor, aDirty, aImage, + aSamplingFilter, aImageFlags, aExtendMode); + + if (!params.shouldDraw) { + return result; + } + + { + gfxContextMatrixAutoSaveRestore contextMatrixRestorer(&aContext); + + aContext.SetMatrixDouble(params.imageSpaceToDeviceSpace); + + SVGImageContext newContext = aSVGContext; + if (!aSVGContext.GetViewportSize()) { + newContext.SetViewportSize(Some(params.svgViewportSize)); + } + + result = aImage->Draw(&aContext, params.size, params.region, + imgIContainer::FRAME_CURRENT, aSamplingFilter, + newContext, aImageFlags, aOpacity); + } + + return result; +} + +/* static */ +ImgDrawResult nsLayoutUtils::DrawSingleUnscaledImage( + gfxContext& aContext, nsPresContext* aPresContext, imgIContainer* aImage, + const SamplingFilter aSamplingFilter, const nsPoint& aDest, + const nsRect* aDirty, const SVGImageContext& aSVGContext, + uint32_t aImageFlags, const nsRect* aSourceArea) { + CSSIntSize imageSize; + aImage->GetWidth(&imageSize.width); + aImage->GetHeight(&imageSize.height); + aImage->GetResolution().ApplyTo(imageSize.width, imageSize.height); + + if (imageSize.width < 1 || imageSize.height < 1) { + NS_WARNING("Image width or height is non-positive"); + return ImgDrawResult::TEMPORARY_ERROR; + } + + nsSize size(CSSPixel::ToAppUnits(imageSize)); + nsRect source; + if (aSourceArea) { + source = *aSourceArea; + } else { + source.SizeTo(size); + } + + nsRect dest(aDest - source.TopLeft(), size); + nsRect fill(aDest, source.Size()); + // Ensure that only a single image tile is drawn. If aSourceArea extends + // outside the image bounds, we want to honor the aSourceArea-to-aDest + // translation but we don't want to actually tile the image. + fill.IntersectRect(fill, dest); + return DrawImageInternal(aContext, aPresContext, aImage, aSamplingFilter, + dest, fill, aDest, aDirty ? *aDirty : dest, + aSVGContext, aImageFlags); +} + +/* static */ +ImgDrawResult nsLayoutUtils::DrawSingleImage( + gfxContext& aContext, nsPresContext* aPresContext, imgIContainer* aImage, + SamplingFilter aSamplingFilter, const nsRect& aDest, const nsRect& aDirty, + const SVGImageContext& aSVGContext, uint32_t aImageFlags, + const nsPoint* aAnchorPoint, const nsRect* aSourceArea) { + nscoord appUnitsPerCSSPixel = AppUnitsPerCSSPixel(); + // NOTE(emilio): We can hardcode resolution to 1 here, since we're interested + // in the actual image pixels, for snapping purposes, not on the adjusted + // size. + CSSIntSize pixelImageSize(ComputeSizeForDrawingWithFallback( + aImage, ImageResolution(), aDest.Size())); + if (pixelImageSize.width < 1 || pixelImageSize.height < 1) { + NS_ASSERTION(pixelImageSize.width >= 0 && pixelImageSize.height >= 0, + "Image width or height is negative"); + return ImgDrawResult::SUCCESS; // no point in drawing a zero size image + } + + nsSize imageSize(CSSPixel::ToAppUnits(pixelImageSize)); + nsRect source; + nsCOMPtr<imgIContainer> image; + if (aSourceArea) { + source = *aSourceArea; + nsIntRect subRect(source.x, source.y, source.width, source.height); + subRect.ScaleInverseRoundOut(appUnitsPerCSSPixel); + image = ImageOps::Clip(aImage, subRect); + + nsRect imageRect; + imageRect.SizeTo(imageSize); + nsRect clippedSource = imageRect.Intersect(source); + + source -= clippedSource.TopLeft(); + imageSize = clippedSource.Size(); + } else { + source.SizeTo(imageSize); + image = aImage; + } + + nsRect dest = GetWholeImageDestination(imageSize, source, aDest); + + // Ensure that only a single image tile is drawn. If aSourceArea extends + // outside the image bounds, we want to honor the aSourceArea-to-aDest + // transform but we don't want to actually tile the image. + nsRect fill; + fill.IntersectRect(aDest, dest); + return DrawImageInternal(aContext, aPresContext, image, aSamplingFilter, dest, + fill, aAnchorPoint ? *aAnchorPoint : fill.TopLeft(), + aDirty, aSVGContext, aImageFlags); +} + +/* static */ +void nsLayoutUtils::ComputeSizeForDrawing( + imgIContainer* aImage, const ImageResolution& aResolution, + /* outparam */ CSSIntSize& aImageSize, + /* outparam */ AspectRatio& aIntrinsicRatio, + /* outparam */ bool& aGotWidth, + /* outparam */ bool& aGotHeight) { + aGotWidth = NS_SUCCEEDED(aImage->GetWidth(&aImageSize.width)); + aGotHeight = NS_SUCCEEDED(aImage->GetHeight(&aImageSize.height)); + Maybe<AspectRatio> intrinsicRatio = aImage->GetIntrinsicRatio(); + aIntrinsicRatio = intrinsicRatio.valueOr(AspectRatio()); + + if (aGotWidth) { + aResolution.ApplyXTo(aImageSize.width); + } + if (aGotHeight) { + aResolution.ApplyYTo(aImageSize.height); + } + + if (!(aGotWidth && aGotHeight) && intrinsicRatio.isNothing()) { + // We hit an error (say, because the image failed to load or couldn't be + // decoded) and should return zero size. + aGotWidth = aGotHeight = true; + aImageSize = CSSIntSize(0, 0); + } +} + +/* static */ +CSSIntSize nsLayoutUtils::ComputeSizeForDrawingWithFallback( + imgIContainer* aImage, const ImageResolution& aResolution, + const nsSize& aFallbackSize) { + CSSIntSize imageSize; + AspectRatio imageRatio; + bool gotHeight, gotWidth; + ComputeSizeForDrawing(aImage, aResolution, imageSize, imageRatio, gotWidth, + gotHeight); + + // If we didn't get both width and height, try to compute them using the + // intrinsic ratio of the image. + if (gotWidth != gotHeight) { + if (!gotWidth) { + if (imageRatio) { + imageSize.width = imageRatio.ApplyTo(imageSize.height); + gotWidth = true; + } + } else { + if (imageRatio) { + imageSize.height = imageRatio.Inverted().ApplyTo(imageSize.width); + gotHeight = true; + } + } + } + + // If we still don't have a width or height, just use the fallback size the + // caller provided. + if (!gotWidth) { + imageSize.width = + nsPresContext::AppUnitsToIntCSSPixels(aFallbackSize.width); + } + if (!gotHeight) { + imageSize.height = + nsPresContext::AppUnitsToIntCSSPixels(aFallbackSize.height); + } + + return imageSize; +} + +/* static */ LayerIntRect SnapRectForImage( + const gfx::Matrix& aTransform, const gfx::MatrixScales& aScaleFactors, + const LayoutDeviceRect& aRect) { + // Attempt to snap pixels, the same as ComputeSnappedImageDrawingParameters. + // Any changes to the algorithm here will need to be reflected there. + bool snapped = false; + LayerIntRect snapRect; + if (!aTransform.HasNonAxisAlignedTransform() && aTransform._11 > 0.0 && + aTransform._22 > 0.0) { + gfxRect rect(gfxPoint(aRect.X(), aRect.Y()), + gfxSize(aRect.Width(), aRect.Height())); + + gfxPoint p1 = + ThebesPoint(aTransform.TransformPoint(ToPoint(rect.TopLeft()))); + gfxPoint p2 = + ThebesPoint(aTransform.TransformPoint(ToPoint(rect.TopRight()))); + gfxPoint p3 = + ThebesPoint(aTransform.TransformPoint(ToPoint(rect.BottomRight()))); + + if (p2 == gfxPoint(p1.x, p3.y) || p2 == gfxPoint(p3.x, p1.y)) { + p1.Round(); + p3.Round(); + + IntPoint p1i(int32_t(p1.x), int32_t(p1.y)); + IntPoint p3i(int32_t(p3.x), int32_t(p3.y)); + + snapRect.MoveTo(std::min(p1i.x, p3i.x), std::min(p1i.y, p3i.y)); + snapRect.SizeTo(std::max(p1i.x, p3i.x) - snapRect.X(), + std::max(p1i.y, p3i.y) - snapRect.Y()); + snapped = true; + } + } + + if (!snapped) { + // If we couldn't snap directly with the transform, we need to go best + // effort in layer pixels. + snapRect = RoundedToInt( + aRect * LayoutDeviceToLayerScale2D::FromUnknownScale(aScaleFactors)); + } + + // An empty size is unacceptable so we ensure our suggested size is at least + // 1 pixel wide/tall. + if (snapRect.Width() < 1) { + snapRect.SetWidth(1); + } + if (snapRect.Height() < 1) { + snapRect.SetHeight(1); + } + return snapRect; +} + +/* static */ +IntSize nsLayoutUtils::ComputeImageContainerDrawingParameters( + imgIContainer* aImage, nsIFrame* aForFrame, + const LayoutDeviceRect& aDestRect, const LayoutDeviceRect& aFillRect, + const StackingContextHelper& aSc, uint32_t aFlags, + SVGImageContext& aSVGContext, Maybe<ImageIntRegion>& aRegion) { + MOZ_ASSERT(aImage); + MOZ_ASSERT(aForFrame); + + MatrixScales scaleFactors = aSc.GetInheritedScale(); + SamplingFilter samplingFilter = + nsLayoutUtils::GetSamplingFilterForFrame(aForFrame); + + // Compute our SVG context parameters, if any. Don't replace the viewport + // size if it was already set, prefer what the caller gave. + SVGImageContext::MaybeStoreContextPaint(aSVGContext, aForFrame, aImage); + if ((scaleFactors.xScale != 1.0 || scaleFactors.yScale != 1.0) && + aImage->GetType() == imgIContainer::TYPE_VECTOR && + (!aSVGContext.GetViewportSize())) { + gfxSize gfxDestSize(aDestRect.Width(), aDestRect.Height()); + IntSize viewportSize = aImage->OptimalImageSizeForDest( + gfxDestSize, imgIContainer::FRAME_CURRENT, samplingFilter, aFlags); + + CSSIntSize cssViewportSize(viewportSize.width, viewportSize.height); + aSVGContext.SetViewportSize(Some(cssViewportSize)); + } + + const gfx::Matrix& itm = aSc.GetInheritedTransform(); + LayerIntRect destRect = SnapRectForImage(itm, scaleFactors, aDestRect); + + // Since we always decode entire raster images, we only care about the + // ImageIntRegion for vector images, for which we may only draw part of in + // some cases. + if (aImage->GetType() != imgIContainer::TYPE_VECTOR) { + return aImage->OptimalImageSizeForDest( + gfxSize(destRect.Width(), destRect.Height()), + imgIContainer::FRAME_CURRENT, samplingFilter, aFlags); + } + + // We only use the region rect with blob recordings. This is because when we + // rasterize an SVG image in process, we always create a complete + // rasterization of the whole image which can be given to any caller, while + // we support partial rasterization with the blob recordings. + if (aFlags & imgIContainer::FLAG_RECORD_BLOB) { + // If the dest rect contains the fill rect, then we are only displaying part + // of the vector image. We need to calculate the restriction region to avoid + // drawing more than we need, and sampling outside the desired bounds. + LayerIntRect clipRect = SnapRectForImage(itm, scaleFactors, aFillRect); + if (destRect.Contains(clipRect)) { + LayerIntRect restrictRect = destRect.Intersect(clipRect); + restrictRect.MoveBy(-destRect.TopLeft()); + + if (restrictRect.Width() < 1) { + restrictRect.SetWidth(1); + } + if (restrictRect.Height() < 1) { + restrictRect.SetHeight(1); + } + + if (restrictRect.X() != 0 || restrictRect.Y() != 0 || + restrictRect.Size() != destRect.Size()) { + IntRect sampleRect = restrictRect.ToUnknownRect(); + aRegion = Some(ImageIntRegion::CreateWithSamplingRestriction( + sampleRect, sampleRect, ExtendMode::CLAMP)); + } + } + } + + // VectorImage::OptimalImageSizeForDest will just round up, but we already + // have an integer size. + return destRect.Size().ToUnknownSize(); +} + +/* static */ +nsPoint nsLayoutUtils::GetBackgroundFirstTilePos(const nsPoint& aDest, + const nsPoint& aFill, + const nsSize& aRepeatSize) { + return nsPoint(NSToIntFloor(float(aFill.x - aDest.x) / aRepeatSize.width) * + aRepeatSize.width, + NSToIntFloor(float(aFill.y - aDest.y) / aRepeatSize.height) * + aRepeatSize.height) + + aDest; +} + +/* static */ +ImgDrawResult nsLayoutUtils::DrawBackgroundImage( + gfxContext& aContext, nsIFrame* aForFrame, nsPresContext* aPresContext, + imgIContainer* aImage, SamplingFilter aSamplingFilter, const nsRect& aDest, + const nsRect& aFill, const nsSize& aRepeatSize, const nsPoint& aAnchor, + const nsRect& aDirty, uint32_t aImageFlags, ExtendMode aExtendMode, + float aOpacity) { + AUTO_PROFILER_LABEL("nsLayoutUtils::DrawBackgroundImage", + GRAPHICS_Rasterization); + + CSSIntSize destCSSSize{nsPresContext::AppUnitsToIntCSSPixels(aDest.width), + nsPresContext::AppUnitsToIntCSSPixels(aDest.height)}; + + SVGImageContext svgContext(Some(destCSSSize)); + SVGImageContext::MaybeStoreContextPaint(svgContext, aForFrame, aImage); + + /* Fast path when there is no need for image spacing */ + if (aRepeatSize.width == aDest.width && aRepeatSize.height == aDest.height) { + return DrawImageInternal(aContext, aPresContext, aImage, aSamplingFilter, + aDest, aFill, aAnchor, aDirty, svgContext, + aImageFlags, aExtendMode, aOpacity); + } + + const nsPoint firstTilePos = + GetBackgroundFirstTilePos(aDest.TopLeft(), aFill.TopLeft(), aRepeatSize); + const nscoord xMost = aFill.XMost(); + const nscoord repeatWidth = aRepeatSize.width; + const nscoord yMost = aFill.YMost(); + const nscoord repeatHeight = aRepeatSize.height; + nsRect dest(0, 0, aDest.width, aDest.height); + nsPoint anchor = aAnchor; + for (nscoord x = firstTilePos.x; x < xMost; x += repeatWidth) { + for (nscoord y = firstTilePos.y; y < yMost; y += repeatHeight) { + dest.x = x; + dest.y = y; + ImgDrawResult result = DrawImageInternal( + aContext, aPresContext, aImage, aSamplingFilter, dest, dest, anchor, + aDirty, svgContext, aImageFlags, ExtendMode::CLAMP, aOpacity); + anchor.y += repeatHeight; + if (result != ImgDrawResult::SUCCESS) { + return result; + } + } + anchor.x += repeatWidth; + anchor.y = aAnchor.y; + } + + return ImgDrawResult::SUCCESS; +} + +/* static */ +ImgDrawResult nsLayoutUtils::DrawImage( + gfxContext& aContext, ComputedStyle* aComputedStyle, + nsPresContext* aPresContext, imgIContainer* aImage, + const SamplingFilter aSamplingFilter, const nsRect& aDest, + const nsRect& aFill, const nsPoint& aAnchor, const nsRect& aDirty, + uint32_t aImageFlags, float aOpacity) { + SVGImageContext svgContext; + SVGImageContext::MaybeStoreContextPaint(svgContext, *aPresContext, + *aComputedStyle, aImage); + + return DrawImageInternal(aContext, aPresContext, aImage, aSamplingFilter, + aDest, aFill, aAnchor, aDirty, svgContext, + aImageFlags, ExtendMode::CLAMP, aOpacity); +} + +/* static */ +nsRect nsLayoutUtils::GetWholeImageDestination(const nsSize& aWholeImageSize, + const nsRect& aImageSourceArea, + const nsRect& aDestArea) { + double scaleX = double(aDestArea.width) / aImageSourceArea.width; + double scaleY = double(aDestArea.height) / aImageSourceArea.height; + nscoord destOffsetX = NSToCoordRound(aImageSourceArea.x * scaleX); + nscoord destOffsetY = NSToCoordRound(aImageSourceArea.y * scaleY); + nscoord wholeSizeX = NSToCoordRound(aWholeImageSize.width * scaleX); + nscoord wholeSizeY = NSToCoordRound(aWholeImageSize.height * scaleY); + return nsRect(aDestArea.TopLeft() - nsPoint(destOffsetX, destOffsetY), + nsSize(wholeSizeX, wholeSizeY)); +} + +/* static */ +already_AddRefed<imgIContainer> nsLayoutUtils::OrientImage( + imgIContainer* aContainer, const StyleImageOrientation& aOrientation) { + MOZ_ASSERT(aContainer, "Should have an image container"); + nsCOMPtr<imgIContainer> img(aContainer); + + switch (aOrientation) { + case StyleImageOrientation::FromImage: + break; + case StyleImageOrientation::None: + img = ImageOps::Unorient(img); + break; + } + + return img.forget(); +} + +static bool NonZeroCorner(const LengthPercentage& aLength) { + // Since negative results are clamped to 0, check > 0. + return aLength.Resolve(nscoord_MAX) > 0 || aLength.Resolve(0) > 0; +} + +/* static */ +bool nsLayoutUtils::HasNonZeroCorner(const BorderRadius& aCorners) { + for (const auto corner : mozilla::AllPhysicalHalfCorners()) { + if (NonZeroCorner(aCorners.Get(corner))) return true; + } + return false; +} + +// aCorner is a "full corner" value, i.e. eCornerTopLeft etc. +static bool IsCornerAdjacentToSide(uint8_t aCorner, Side aSide) { + static_assert((int)eSideTop == eCornerTopLeft, "Check for Full Corner"); + static_assert((int)eSideRight == eCornerTopRight, "Check for Full Corner"); + static_assert((int)eSideBottom == eCornerBottomRight, + "Check for Full Corner"); + static_assert((int)eSideLeft == eCornerBottomLeft, "Check for Full Corner"); + static_assert((int)eSideTop == ((eCornerTopRight - 1) & 3), + "Check for Full Corner"); + static_assert((int)eSideRight == ((eCornerBottomRight - 1) & 3), + "Check for Full Corner"); + static_assert((int)eSideBottom == ((eCornerBottomLeft - 1) & 3), + "Check for Full Corner"); + static_assert((int)eSideLeft == ((eCornerTopLeft - 1) & 3), + "Check for Full Corner"); + + return aSide == aCorner || aSide == ((aCorner - 1) & 3); +} + +/* static */ +bool nsLayoutUtils::HasNonZeroCornerOnSide(const BorderRadius& aCorners, + Side aSide) { + static_assert(eCornerTopLeftX / 2 == eCornerTopLeft, + "Check for Non Zero on side"); + static_assert(eCornerTopLeftY / 2 == eCornerTopLeft, + "Check for Non Zero on side"); + static_assert(eCornerTopRightX / 2 == eCornerTopRight, + "Check for Non Zero on side"); + static_assert(eCornerTopRightY / 2 == eCornerTopRight, + "Check for Non Zero on side"); + static_assert(eCornerBottomRightX / 2 == eCornerBottomRight, + "Check for Non Zero on side"); + static_assert(eCornerBottomRightY / 2 == eCornerBottomRight, + "Check for Non Zero on side"); + static_assert(eCornerBottomLeftX / 2 == eCornerBottomLeft, + "Check for Non Zero on side"); + static_assert(eCornerBottomLeftY / 2 == eCornerBottomLeft, + "Check for Non Zero on side"); + + for (const auto corner : mozilla::AllPhysicalHalfCorners()) { + // corner is a "half corner" value, so dividing by two gives us a + // "full corner" value. + if (NonZeroCorner(aCorners.Get(corner)) && + IsCornerAdjacentToSide(corner / 2, aSide)) + return true; + } + return false; +} + +/* static */ +nsTransparencyMode nsLayoutUtils::GetFrameTransparency( + nsIFrame* aBackgroundFrame, nsIFrame* aCSSRootFrame) { + if (aCSSRootFrame->StyleEffects()->mOpacity < 1.0f) + return eTransparencyTransparent; + + if (HasNonZeroCorner(aCSSRootFrame->StyleBorder()->mBorderRadius)) + return eTransparencyTransparent; + + StyleAppearance appearance = + aCSSRootFrame->StyleDisplay()->EffectiveAppearance(); + + if (appearance == StyleAppearance::MozWinBorderlessGlass) { + return eTransparencyBorderlessGlass; + } + + nsITheme::Transparency transparency; + if (aCSSRootFrame->IsThemed(&transparency)) { + return transparency == nsITheme::eTransparent ? eTransparencyTransparent + : eTransparencyOpaque; + } + + // We need an uninitialized window to be treated as opaque because doing + // otherwise breaks window display effects on some platforms, specifically + // Vista. (bug 450322) + if (aBackgroundFrame->IsViewportFrame() && + !aBackgroundFrame->PrincipalChildList().FirstChild()) { + return eTransparencyOpaque; + } + + const ComputedStyle* bgSC = nsCSSRendering::FindBackground(aBackgroundFrame); + if (!bgSC) { + return eTransparencyTransparent; + } + const nsStyleBackground* bg = bgSC->StyleBackground(); + if (NS_GET_A(bg->BackgroundColor(bgSC)) < 255 || + // bottom layer's clip is used for the color + bg->BottomLayer().mClip != StyleGeometryBox::BorderBox) { + return eTransparencyTransparent; + } + return eTransparencyOpaque; +} + +/* static */ +bool nsLayoutUtils::IsPopup(const nsIFrame* aFrame) { + // Optimization: the frame can't possibly be a popup if it has no view. + if (!aFrame->HasView()) { + NS_ASSERTION(!aFrame->IsMenuPopupFrame(), "popup frame must have a view"); + return false; + } + return aFrame->IsMenuPopupFrame(); +} + +/* static */ +nsIFrame* nsLayoutUtils::GetDisplayRootFrame(nsIFrame* aFrame) { + return const_cast<nsIFrame*>( + nsLayoutUtils::GetDisplayRootFrame(const_cast<const nsIFrame*>(aFrame))); +} + +/* static */ +const nsIFrame* nsLayoutUtils::GetDisplayRootFrame(const nsIFrame* aFrame) { + // We could use GetRootPresContext() here if the + // NS_FRAME_IN_POPUP frame bit is set. + const nsIFrame* f = aFrame; + for (;;) { + if (!f->HasAnyStateBits(NS_FRAME_IN_POPUP)) { + f = f->PresShell()->GetRootFrame(); + if (!f) { + return aFrame; + } + } else if (IsPopup(f)) { + return f; + } + nsIFrame* parent = GetCrossDocParentFrameInProcess(f); + if (!parent) return f; + f = parent; + } +} + +/* static */ +nsIFrame* nsLayoutUtils::GetReferenceFrame(nsIFrame* aFrame) { + nsIFrame* f = aFrame; + for (;;) { + if (f->IsTransformed() || f->IsPreserve3DLeaf() || IsPopup(f)) { + return f; + } + nsIFrame* parent = GetCrossDocParentFrameInProcess(f); + if (!parent) { + return f; + } + f = parent; + } +} + +/* static */ gfx::ShapedTextFlags nsLayoutUtils::GetTextRunFlagsForStyle( + const ComputedStyle* aComputedStyle, nsPresContext* aPresContext, + const nsStyleFont* aStyleFont, const nsStyleText* aStyleText, + nscoord aLetterSpacing) { + gfx::ShapedTextFlags result = gfx::ShapedTextFlags(); + if (aLetterSpacing != 0 || + aStyleText->mTextJustify == StyleTextJustify::InterCharacter) { + result |= gfx::ShapedTextFlags::TEXT_DISABLE_OPTIONAL_LIGATURES; + } + if (aStyleText->mMozControlCharacterVisibility == + StyleMozControlCharacterVisibility::Hidden) { + result |= gfx::ShapedTextFlags::TEXT_HIDE_CONTROL_CHARACTERS; + } + switch (aComputedStyle->StyleText()->mTextRendering) { + case StyleTextRendering::Optimizespeed: + result |= gfx::ShapedTextFlags::TEXT_OPTIMIZE_SPEED; + break; + case StyleTextRendering::Auto: + if (aPresContext && aStyleFont->mFont.size.ToCSSPixels() < + aPresContext->GetAutoQualityMinFontSize()) { + result |= gfx::ShapedTextFlags::TEXT_OPTIMIZE_SPEED; + } + break; + default: + break; + } + return result | GetTextRunOrientFlagsForStyle(aComputedStyle); +} + +/* static */ gfx::ShapedTextFlags nsLayoutUtils::GetTextRunOrientFlagsForStyle( + const ComputedStyle* aComputedStyle) { + auto writingMode = aComputedStyle->StyleVisibility()->mWritingMode; + switch (writingMode) { + case StyleWritingModeProperty::HorizontalTb: + return gfx::ShapedTextFlags::TEXT_ORIENT_HORIZONTAL; + + case StyleWritingModeProperty::VerticalLr: + case StyleWritingModeProperty::VerticalRl: + switch (aComputedStyle->StyleVisibility()->mTextOrientation) { + case StyleTextOrientation::Mixed: + return gfx::ShapedTextFlags::TEXT_ORIENT_VERTICAL_MIXED; + case StyleTextOrientation::Upright: + return gfx::ShapedTextFlags::TEXT_ORIENT_VERTICAL_UPRIGHT; + case StyleTextOrientation::Sideways: + return gfx::ShapedTextFlags::TEXT_ORIENT_VERTICAL_SIDEWAYS_RIGHT; + default: + MOZ_ASSERT_UNREACHABLE("unknown text-orientation"); + return gfx::ShapedTextFlags(); + } + + case StyleWritingModeProperty::SidewaysLr: + return gfx::ShapedTextFlags::TEXT_ORIENT_VERTICAL_SIDEWAYS_LEFT; + + case StyleWritingModeProperty::SidewaysRl: + return gfx::ShapedTextFlags::TEXT_ORIENT_VERTICAL_SIDEWAYS_RIGHT; + + default: + MOZ_ASSERT_UNREACHABLE("unknown writing-mode"); + return gfx::ShapedTextFlags(); + } +} + +/* static */ +void nsLayoutUtils::GetRectDifferenceStrips(const nsRect& aR1, + const nsRect& aR2, nsRect* aHStrip, + nsRect* aVStrip) { + NS_ASSERTION(aR1.TopLeft() == aR2.TopLeft(), + "expected rects at the same position"); + nsRect unionRect(aR1.x, aR1.y, std::max(aR1.width, aR2.width), + std::max(aR1.height, aR2.height)); + nscoord VStripStart = std::min(aR1.width, aR2.width); + nscoord HStripStart = std::min(aR1.height, aR2.height); + *aVStrip = unionRect; + aVStrip->x += VStripStart; + aVStrip->width -= VStripStart; + *aHStrip = unionRect; + aHStrip->y += HStripStart; + aHStrip->height -= HStripStart; +} + +nsDeviceContext* nsLayoutUtils::GetDeviceContextForScreenInfo( + nsPIDOMWindowOuter* aWindow) { + if (!aWindow) { + return nullptr; + } + + nsCOMPtr<nsIDocShell> docShell = aWindow->GetDocShell(); + while (docShell) { + // Now make sure our size is up to date. That will mean that the device + // context does the right thing on multi-monitor systems when we return it + // to the caller. It will also make sure that our prescontext has been + // created, if we're supposed to have one. + nsCOMPtr<nsPIDOMWindowOuter> win = docShell->GetWindow(); + if (!win) { + // No reason to go on + return nullptr; + } + + win->EnsureSizeAndPositionUpToDate(); + + RefPtr<nsPresContext> presContext = docShell->GetPresContext(); + if (presContext) { + nsDeviceContext* context = presContext->DeviceContext(); + if (context) { + return context; + } + } + + nsCOMPtr<nsIDocShellTreeItem> parentItem; + docShell->GetInProcessParent(getter_AddRefs(parentItem)); + docShell = do_QueryInterface(parentItem); + } + + return nullptr; +} + +/* static */ +bool nsLayoutUtils::IsReallyFixedPos(const nsIFrame* aFrame) { + MOZ_ASSERT(aFrame->StyleDisplay()->mPosition == StylePositionProperty::Fixed, + "IsReallyFixedPos called on non-'position:fixed' frame"); + return MayBeReallyFixedPos(aFrame); +} + +/* static */ +bool nsLayoutUtils::MayBeReallyFixedPos(const nsIFrame* aFrame) { + MOZ_ASSERT(aFrame->GetParent(), + "MayBeReallyFixedPos called on frame not in tree"); + LayoutFrameType parentType = aFrame->GetParent()->Type(); + return parentType == LayoutFrameType::Viewport || + parentType == LayoutFrameType::PageContent; +} + +/* static */ +bool nsLayoutUtils::IsInPositionFixedSubtree(const nsIFrame* aFrame) { + for (const nsIFrame* f = aFrame; f; f = f->GetParent()) { + if (f->StyleDisplay()->mPosition == StylePositionProperty::Fixed && + nsLayoutUtils::IsReallyFixedPos(f)) { + return true; + } + } + return false; +} + +SurfaceFromElementResult nsLayoutUtils::SurfaceFromOffscreenCanvas( + OffscreenCanvas* aOffscreenCanvas, uint32_t aSurfaceFlags, + RefPtr<DrawTarget>& aTarget) { + SurfaceFromElementResult result; + + IntSize size = aOffscreenCanvas->GetWidthHeight(); + + result.mSourceSurface = + aOffscreenCanvas->GetSurfaceSnapshot(&result.mAlphaType); + if (!result.mSourceSurface) { + // If the element doesn't have a context then we won't get a snapshot. The + // canvas spec wants us to not error and just draw nothing, so return an + // empty surface. + result.mAlphaType = gfxAlphaType::Opaque; + RefPtr<DrawTarget> ref = + aTarget ? aTarget : gfxPlatform::ThreadLocalScreenReferenceDrawTarget(); + if (ref->CanCreateSimilarDrawTarget(size, SurfaceFormat::B8G8R8A8)) { + RefPtr<DrawTarget> dt = + ref->CreateSimilarDrawTarget(size, SurfaceFormat::B8G8R8A8); + if (dt) { + result.mSourceSurface = dt->Snapshot(); + } + } + } else if (aTarget) { + RefPtr<SourceSurface> opt = + aTarget->OptimizeSourceSurface(result.mSourceSurface); + if (opt) { + result.mSourceSurface = opt; + } + } + + result.mHasSize = true; + result.mSize = size; + result.mIntrinsicSize = size; + result.mIsWriteOnly = aOffscreenCanvas->IsWriteOnly(); + + nsIGlobalObject* global = aOffscreenCanvas->GetParentObject(); + if (global) { + result.mPrincipal = global->PrincipalOrNull(); + } + + return result; +} + +SurfaceFromElementResult nsLayoutUtils::SurfaceFromImageBitmap( + mozilla::dom::ImageBitmap* aImageBitmap, uint32_t aSurfaceFlags) { + SurfaceFromElementResult result; + RefPtr<DrawTarget> dt = Factory::CreateDrawTarget( + BackendType::SKIA, IntSize(1, 1), SurfaceFormat::B8G8R8A8); + + // An ImageBitmap, not being a DOM element, only has `origin-clean` + // (via our `IsWriteOnly`), and does not participate in CORS. + // Right now we mark this by setting mCORSUsed to true. + result.mCORSUsed = true; + result.mIsWriteOnly = aImageBitmap->IsWriteOnly(); + result.mSourceSurface = aImageBitmap->PrepareForDrawTarget(dt); + + if (result.mSourceSurface) { + result.mSize = result.mIntrinsicSize = result.mSourceSurface->GetSize(); + result.mHasSize = true; + result.mAlphaType = IsOpaque(result.mSourceSurface->GetFormat()) + ? gfxAlphaType::Opaque + : gfxAlphaType::Premult; + } + + nsCOMPtr<nsIGlobalObject> global = aImageBitmap->GetParentObject(); + if (global) { + result.mPrincipal = global->PrincipalOrNull(); + } + + return result; +} + +static RefPtr<SourceSurface> ScaleSourceSurface(SourceSurface& aSurface, + const IntSize& aTargetSize) { + const IntSize surfaceSize = aSurface.GetSize(); + + MOZ_ASSERT(surfaceSize != aTargetSize); + MOZ_ASSERT(!surfaceSize.IsEmpty()); + MOZ_ASSERT(!aTargetSize.IsEmpty()); + + RefPtr<DrawTarget> dt = Factory::CreateDrawTarget( + gfxVars::ContentBackend(), aTargetSize, aSurface.GetFormat()); + + if (!dt || !dt->IsValid()) { + return nullptr; + } + + RefPtr<gfxContext> context = gfxContext::CreateOrNull(dt); + MOZ_ASSERT(context); + + dt->DrawSurface(&aSurface, Rect(Point(), Size(aTargetSize)), + Rect(Point(), Size(surfaceSize))); + return dt->GetBackingSurface(); +} + +SurfaceFromElementResult nsLayoutUtils::SurfaceFromElement( + nsIImageLoadingContent* aElement, const Maybe<int32_t>& aResizeWidth, + const Maybe<int32_t>& aResizeHeight, uint32_t aSurfaceFlags, + RefPtr<DrawTarget>& aTarget) { + SurfaceFromElementResult result; + nsresult rv; + + nsCOMPtr<imgIRequest> imgRequest; + rv = aElement->GetRequest(nsIImageLoadingContent::CURRENT_REQUEST, + getter_AddRefs(imgRequest)); + if (NS_FAILED(rv)) { + return result; + } + + if (!imgRequest) { + // There's no image request. This is either because a request for + // a non-empty URI failed, or the URI is the empty string. + nsCOMPtr<nsIURI> currentURI; + aElement->GetCurrentURI(getter_AddRefs(currentURI)); + if (!currentURI) { + // Treat the empty URI as available instead of broken state. + result.mHasSize = true; + } + return result; + } + + uint32_t status; + imgRequest->GetImageStatus(&status); + result.mHasSize = status & imgIRequest::STATUS_SIZE_AVAILABLE; + if ((status & imgIRequest::STATUS_LOAD_COMPLETE) == 0) { + // Spec says to use GetComplete, but that only works on + // HTMLImageElement, and we support all sorts of other stuff + // here. Do this for now pending spec clarification. + result.mIsStillLoading = (status & imgIRequest::STATUS_ERROR) == 0; + return result; + } + + nsCOMPtr<nsIPrincipal> principal; + rv = imgRequest->GetImagePrincipal(getter_AddRefs(principal)); + if (NS_FAILED(rv)) { + return result; + } + + nsCOMPtr<imgIContainer> imgContainer; + rv = imgRequest->GetImage(getter_AddRefs(imgContainer)); + if (NS_FAILED(rv)) { + return result; + } + + nsCOMPtr<nsIContent> content = do_QueryInterface(aElement); + + // Ensure that the image is oriented the same way as it's displayed + // if the image request is of the same origin. + auto orientation = + content->GetPrimaryFrame() + ? content->GetPrimaryFrame()->StyleVisibility()->UsedImageOrientation( + imgRequest) + : nsStyleVisibility::UsedImageOrientation( + imgRequest, StyleImageOrientation::FromImage); + imgContainer = OrientImage(imgContainer, orientation); + + const bool noRasterize = aSurfaceFlags & SFE_NO_RASTERIZING_VECTORS; + + uint32_t whichFrame = aSurfaceFlags & SFE_WANT_FIRST_FRAME_IF_IMAGE + ? (uint32_t)imgIContainer::FRAME_FIRST + : (uint32_t)imgIContainer::FRAME_CURRENT; + const bool exactSize = aSurfaceFlags & SFE_EXACT_SIZE_SURFACE; + + uint32_t frameFlags = + imgIContainer::FLAG_SYNC_DECODE | imgIContainer::FLAG_ASYNC_NOTIFY; + if (aSurfaceFlags & SFE_NO_COLORSPACE_CONVERSION) + frameFlags |= imgIContainer::FLAG_DECODE_NO_COLORSPACE_CONVERSION; + if (aSurfaceFlags & SFE_ALLOW_NON_PREMULT) { + frameFlags |= imgIContainer::FLAG_DECODE_NO_PREMULTIPLY_ALPHA; + } + + int32_t imgWidth, imgHeight; + HTMLImageElement* element = HTMLImageElement::FromNodeOrNull(content); + if (aSurfaceFlags & SFE_USE_ELEMENT_SIZE_IF_VECTOR && element && + imgContainer->GetType() == imgIContainer::TYPE_VECTOR) { + // We're holding a strong ref to "element" via "content". + imgWidth = MOZ_KnownLive(element)->Width(); + imgHeight = MOZ_KnownLive(element)->Height(); + } else { + auto res = imgContainer->GetResolution(); + rv = imgContainer->GetWidth(&imgWidth); + if (NS_SUCCEEDED(rv)) { + res.ApplyXTo(imgWidth); + } else if (aResizeWidth.isSome()) { + imgWidth = *aResizeWidth; + rv = NS_OK; + } + nsresult rv2 = imgContainer->GetHeight(&imgHeight); + if (NS_SUCCEEDED(rv2)) { + res.ApplyYTo(imgHeight); + } else if (aResizeHeight.isSome()) { + imgHeight = *aResizeHeight; + rv2 = NS_OK; + } + if (NS_FAILED(rv) || NS_FAILED(rv2)) return result; + } + result.mSize = result.mIntrinsicSize = IntSize(imgWidth, imgHeight); + + if (!noRasterize || imgContainer->GetType() == imgIContainer::TYPE_RASTER) { + result.mSourceSurface = + imgContainer->GetFrameAtSize(result.mSize, whichFrame, frameFlags); + if (!result.mSourceSurface) { + return result; + } + if (exactSize && result.mSourceSurface->GetSize() != result.mSize) { + result.mSourceSurface = + ScaleSourceSurface(*result.mSourceSurface, result.mSize); + if (!result.mSourceSurface) { + return result; + } + } + // The surface we return is likely to be cached. We don't want to have to + // convert to a surface that's compatible with aTarget each time it's used + // (that would result in terrible performance), so we convert once here + // upfront if aTarget is specified. + if (aTarget) { + RefPtr<SourceSurface> optSurface = + aTarget->OptimizeSourceSurface(result.mSourceSurface); + if (optSurface) { + result.mSourceSurface = optSurface; + } + } + + const auto& format = result.mSourceSurface->GetFormat(); + if (IsOpaque(format)) { + result.mAlphaType = gfxAlphaType::Opaque; + } else if (frameFlags & imgIContainer::FLAG_DECODE_NO_PREMULTIPLY_ALPHA) { + result.mAlphaType = gfxAlphaType::NonPremult; + } else { + result.mAlphaType = gfxAlphaType::Premult; + } + } else { + result.mDrawInfo.mImgContainer = imgContainer; + result.mDrawInfo.mWhichFrame = whichFrame; + result.mDrawInfo.mDrawingFlags = frameFlags; + } + + int32_t corsmode; + if (NS_SUCCEEDED(imgRequest->GetCORSMode(&corsmode))) { + result.mCORSUsed = corsmode != CORS_NONE; + } + + bool hadCrossOriginRedirects = true; + imgRequest->GetHadCrossOriginRedirects(&hadCrossOriginRedirects); + + result.mPrincipal = std::move(principal); + result.mHadCrossOriginRedirects = hadCrossOriginRedirects; + result.mImageRequest = std::move(imgRequest); + result.mIsWriteOnly = CanvasUtils::CheckWriteOnlySecurity( + result.mCORSUsed, result.mPrincipal, result.mHadCrossOriginRedirects); + + return result; +} + +SurfaceFromElementResult nsLayoutUtils::SurfaceFromElement( + HTMLImageElement* aElement, uint32_t aSurfaceFlags, + RefPtr<DrawTarget>& aTarget) { + return SurfaceFromElement(static_cast<nsIImageLoadingContent*>(aElement), + Nothing(), Nothing(), aSurfaceFlags, aTarget); +} + +SurfaceFromElementResult nsLayoutUtils::SurfaceFromElement( + HTMLCanvasElement* aElement, uint32_t aSurfaceFlags, + RefPtr<DrawTarget>& aTarget) { + SurfaceFromElementResult result; + + IntSize size = aElement->GetSize(); + + auto pAlphaType = &result.mAlphaType; + if (!(aSurfaceFlags & SFE_ALLOW_NON_PREMULT)) { + pAlphaType = + nullptr; // Coersce GetSurfaceSnapshot to give us Opaque/Premult only. + } + result.mSourceSurface = aElement->GetSurfaceSnapshot(pAlphaType, aTarget); + if (!result.mSourceSurface) { + // If the element doesn't have a context then we won't get a snapshot. The + // canvas spec wants us to not error and just draw nothing, so return an + // empty surface. + result.mAlphaType = gfxAlphaType::Opaque; + RefPtr<DrawTarget> ref = + aTarget ? aTarget + : gfxPlatform::GetPlatform()->ScreenReferenceDrawTarget(); + if (ref->CanCreateSimilarDrawTarget(size, SurfaceFormat::B8G8R8A8)) { + RefPtr<DrawTarget> dt = + ref->CreateSimilarDrawTarget(size, SurfaceFormat::B8G8R8A8); + if (dt) { + result.mSourceSurface = dt->Snapshot(); + } + } + } else if (aTarget) { + RefPtr<SourceSurface> opt = + aTarget->OptimizeSourceSurface(result.mSourceSurface); + if (opt) { + result.mSourceSurface = opt; + } + } + + // Ensure that any future changes to the canvas trigger proper invalidation, + // in case this is being used by -moz-element() + aElement->MarkContextClean(); + + result.mHasSize = true; + result.mSize = size; + result.mIntrinsicSize = size; + result.mPrincipal = aElement->NodePrincipal(); + result.mHadCrossOriginRedirects = false; + result.mIsWriteOnly = aElement->IsWriteOnly(); + + return result; +} + +SurfaceFromElementResult nsLayoutUtils::SurfaceFromElement( + HTMLVideoElement* aElement, uint32_t aSurfaceFlags, + RefPtr<DrawTarget>& aTarget) { + SurfaceFromElementResult result; + result.mAlphaType = gfxAlphaType::Opaque; // Assume opaque. + + if (aElement->ContainsRestrictedContent()) { + return result; + } + + uint16_t readyState = aElement->ReadyState(); + if (readyState == HAVE_NOTHING || readyState == HAVE_METADATA) { + result.mIsStillLoading = true; + return result; + } + + // If it doesn't have a principal, just bail + nsCOMPtr<nsIPrincipal> principal = aElement->GetCurrentVideoPrincipal(); + if (!principal) { + return result; + } + + result.mLayersImage = aElement->GetCurrentImage(); + if (!result.mLayersImage) { + return result; + } + + result.mCORSUsed = aElement->GetCORSMode() != CORS_NONE; + result.mHasSize = true; + result.mSize = result.mLayersImage->GetSize(); + result.mIntrinsicSize = + gfx::IntSize(aElement->VideoWidth(), aElement->VideoHeight()); + result.mPrincipal = std::move(principal); + result.mHadCrossOriginRedirects = aElement->HadCrossOriginRedirects(); + result.mIsWriteOnly = CanvasUtils::CheckWriteOnlySecurity( + result.mCORSUsed, result.mPrincipal, result.mHadCrossOriginRedirects); + + if (aTarget) { + // They gave us a DrawTarget to optimize for, so even though we have a + // layers::Image, we should unconditionally try to grab a SourceSurface and + // try to optimize it. + if ((result.mSourceSurface = result.mLayersImage->GetAsSourceSurface())) { + RefPtr<SourceSurface> opt = + aTarget->OptimizeSourceSurface(result.mSourceSurface); + if (opt) { + result.mSourceSurface = opt; + } + } + } + + return result; +} + +SurfaceFromElementResult nsLayoutUtils::SurfaceFromElement( + dom::Element* aElement, const Maybe<int32_t>& aResizeWidth, + const Maybe<int32_t>& aResizeHeight, uint32_t aSurfaceFlags, + RefPtr<DrawTarget>& aTarget) { + // If it's a <canvas>, we may be able to just grab its internal surface + if (HTMLCanvasElement* canvas = HTMLCanvasElement::FromNodeOrNull(aElement)) { + return SurfaceFromElement(canvas, aSurfaceFlags, aTarget); + } + + // Maybe it's <video>? + if (HTMLVideoElement* video = HTMLVideoElement::FromNodeOrNull(aElement)) { + return SurfaceFromElement(video, aSurfaceFlags, aTarget); + } + + // Finally, check if it's a normal image + nsCOMPtr<nsIImageLoadingContent> imageLoader = do_QueryInterface(aElement); + + if (!imageLoader) { + return SurfaceFromElementResult(); + } + + return SurfaceFromElement(imageLoader, aResizeWidth, aResizeHeight, + aSurfaceFlags, aTarget); +} + +/* static */ +Element* nsLayoutUtils::GetEditableRootContentByContentEditable( + Document* aDocument) { + // If the document is in designMode we should return nullptr. + if (!aDocument || aDocument->IsInDesignMode()) { + return nullptr; + } + + // contenteditable only works with HTML document. + // XXXbz should this test IsHTMLOrXHTML(), or just IsHTML()? + if (!aDocument->IsHTMLOrXHTML()) { + return nullptr; + } + + Element* rootElement = aDocument->GetRootElement(); + if (rootElement && rootElement->IsEditable()) { + return rootElement; + } + + // If there is no editable root element, check its <body> element. + // Note that the body element could be <frameset> element. + Element* bodyElement = aDocument->GetBody(); + if (bodyElement && bodyElement->IsEditable()) { + return bodyElement; + } + return nullptr; +} + +#ifdef DEBUG +/* static */ +void nsLayoutUtils::AssertNoDuplicateContinuations( + nsIFrame* aContainer, const nsFrameList& aFrameList) { + for (nsIFrame* f : aFrameList) { + // Check only later continuations of f; we deal with checking the + // earlier continuations when we hit those earlier continuations in + // the frame list. + for (nsIFrame* c = f; (c = c->GetNextInFlow());) { + NS_ASSERTION(c->GetParent() != aContainer || !aFrameList.ContainsFrame(c), + "Two continuations of the same frame in the same " + "frame list"); + } + } +} + +// Is one of aFrame's ancestors a letter frame? +static bool IsInLetterFrame(nsIFrame* aFrame) { + for (nsIFrame* f = aFrame->GetParent(); f; f = f->GetParent()) { + if (f->IsLetterFrame()) { + return true; + } + } + return false; +} + +/* static */ +void nsLayoutUtils::AssertTreeOnlyEmptyNextInFlows(nsIFrame* aSubtreeRoot) { + NS_ASSERTION(aSubtreeRoot->GetPrevInFlow(), + "frame tree not empty, but caller reported complete status"); + + // Also assert that text frames map no text. + auto [start, end] = aSubtreeRoot->GetOffsets(); + // In some cases involving :first-letter, we'll partially unlink a + // continuation in the middle of a continuation chain from its + // previous and next continuations before destroying it, presumably so + // that we don't also destroy the later continuations. Once we've + // done this, GetOffsets returns incorrect values. + // For examples, see list of tests in + // https://bugzilla.mozilla.org/show_bug.cgi?id=619021#c29 + NS_ASSERTION(start == end || IsInLetterFrame(aSubtreeRoot), + "frame tree not empty, but caller reported complete status"); + + for (const auto& childList : aSubtreeRoot->ChildLists()) { + for (nsIFrame* child : childList.mList) { + nsLayoutUtils::AssertTreeOnlyEmptyNextInFlows(child); + } + } +} +#endif + +static void GetFontFacesForFramesInner( + nsIFrame* aFrame, nsLayoutUtils::UsedFontFaceList& aResult, + nsLayoutUtils::UsedFontFaceTable& aFontFaces, uint32_t aMaxRanges, + bool aSkipCollapsedWhitespace) { + MOZ_ASSERT(aFrame, "NULL frame pointer"); + + if (aFrame->IsTextFrame()) { + if (!aFrame->GetPrevContinuation()) { + nsLayoutUtils::GetFontFacesForText(aFrame, 0, INT32_MAX, true, aResult, + aFontFaces, aMaxRanges, + aSkipCollapsedWhitespace); + } + return; + } + + FrameChildListID childLists[] = {FrameChildListID::Principal, + FrameChildListID::Popup}; + for (size_t i = 0; i < ArrayLength(childLists); ++i) { + for (nsIFrame* child : aFrame->GetChildList(childLists[i])) { + child = nsPlaceholderFrame::GetRealFrameFor(child); + GetFontFacesForFramesInner(child, aResult, aFontFaces, aMaxRanges, + aSkipCollapsedWhitespace); + } + } +} + +/* static */ +nsresult nsLayoutUtils::GetFontFacesForFrames(nsIFrame* aFrame, + UsedFontFaceList& aResult, + UsedFontFaceTable& aFontFaces, + uint32_t aMaxRanges, + bool aSkipCollapsedWhitespace) { + MOZ_ASSERT(aFrame, "NULL frame pointer"); + + while (aFrame) { + GetFontFacesForFramesInner(aFrame, aResult, aFontFaces, aMaxRanges, + aSkipCollapsedWhitespace); + aFrame = GetNextContinuationOrIBSplitSibling(aFrame); + } + + return NS_OK; +} + +static void AddFontsFromTextRun(gfxTextRun* aTextRun, nsTextFrame* aFrame, + gfxSkipCharsIterator& aSkipIter, + const gfxTextRun::Range& aRange, + nsLayoutUtils::UsedFontFaceList& aResult, + nsLayoutUtils::UsedFontFaceTable& aFontFaces, + uint32_t aMaxRanges) { + gfxTextRun::GlyphRunIterator glyphRuns(aTextRun, aRange); + nsIContent* content = aFrame->GetContent(); + int32_t contentLimit = + aFrame->GetContentOffset() + aFrame->GetInFlowContentLength(); + while (glyphRuns.NextRun()) { + gfxFontEntry* fe = glyphRuns.GetGlyphRun()->mFont->GetFontEntry(); + // if we have already listed this face, just make sure the match type is + // recorded + InspectorFontFace* fontFace = aFontFaces.Get(fe); + if (fontFace) { + fontFace->AddMatchType(glyphRuns.GetGlyphRun()->mMatchType); + } else { + // A new font entry we haven't seen before + fontFace = new InspectorFontFace(fe, aTextRun->GetFontGroup(), + glyphRuns.GetGlyphRun()->mMatchType); + aFontFaces.InsertOrUpdate(fe, fontFace); + aResult.AppendElement(fontFace); + } + + // Add this glyph run to the fontFace's list of ranges, unless we have + // already collected as many as wanted. + if (fontFace->RangeCount() < aMaxRanges) { + int32_t start = + aSkipIter.ConvertSkippedToOriginal(glyphRuns.GetStringStart()); + int32_t end = + aSkipIter.ConvertSkippedToOriginal(glyphRuns.GetStringEnd()); + + // Mapping back from textrun offsets ("skipped" offsets that reflect the + // text after whitespace collapsing, etc) to DOM content offsets in the + // original text is ambiguous, because many original characters can + // map to a single skipped offset. aSkipIter.ConvertSkippedToOriginal() + // will return an "original" offset that corresponds to the *end* of + // a collapsed run of characters in this case; but that might extend + // beyond the current content node if the textrun mapped multiple nodes. + // So we clamp the end offset to keep it valid for the content node + // that corresponds to the current textframe. + end = std::min(end, contentLimit); + + if (end > start) { + RefPtr<nsRange> range = + nsRange::Create(content, start, content, end, IgnoreErrors()); + NS_WARNING_ASSERTION(range, + "nsRange::Create() failed to create valid range"); + if (range) { + fontFace->AddRange(range); + } + } + } + } +} + +/* static */ +void nsLayoutUtils::GetFontFacesForText(nsIFrame* aFrame, int32_t aStartOffset, + int32_t aEndOffset, + bool aFollowContinuations, + UsedFontFaceList& aResult, + UsedFontFaceTable& aFontFaces, + uint32_t aMaxRanges, + bool aSkipCollapsedWhitespace) { + MOZ_ASSERT(aFrame, "NULL frame pointer"); + + if (!aFrame->IsTextFrame()) { + return; + } + + if (!aFrame->StyleVisibility()->IsVisible()) { + return; + } + + nsTextFrame* curr = static_cast<nsTextFrame*>(aFrame); + do { + int32_t fstart = std::max(curr->GetContentOffset(), aStartOffset); + int32_t fend = std::min(curr->GetContentEnd(), aEndOffset); + if (fstart >= fend) { + curr = static_cast<nsTextFrame*>(curr->GetNextContinuation()); + continue; + } + + // curr is overlapping with the offset we want + gfxSkipCharsIterator iter = curr->EnsureTextRun(nsTextFrame::eInflated); + gfxTextRun* textRun = curr->GetTextRun(nsTextFrame::eInflated); + if (!textRun) { + NS_WARNING("failed to get textRun, low memory?"); + return; + } + + // include continuations in the range that share the same textrun + nsTextFrame* next = nullptr; + if (aFollowContinuations && fend < aEndOffset) { + next = static_cast<nsTextFrame*>(curr->GetNextContinuation()); + while (next && next->GetTextRun(nsTextFrame::eInflated) == textRun) { + fend = std::min(next->GetContentEnd(), aEndOffset); + next = fend < aEndOffset + ? static_cast<nsTextFrame*>(next->GetNextContinuation()) + : nullptr; + } + } + + if (!aSkipCollapsedWhitespace || (curr->HasAnyNoncollapsedCharacters() && + curr->HasNonSuppressedText())) { + gfxTextRun::Range range(iter.ConvertOriginalToSkipped(fstart), + iter.ConvertOriginalToSkipped(fend)); + AddFontsFromTextRun(textRun, curr, iter, range, aResult, aFontFaces, + aMaxRanges); + } + + curr = next; + } while (aFollowContinuations && curr); +} + +/* static */ +size_t nsLayoutUtils::SizeOfTextRunsForFrames(nsIFrame* aFrame, + MallocSizeOf aMallocSizeOf, + bool clear) { + MOZ_ASSERT(aFrame, "NULL frame pointer"); + + size_t total = 0; + + if (aFrame->IsTextFrame()) { + nsTextFrame* textFrame = static_cast<nsTextFrame*>(aFrame); + for (uint32_t i = 0; i < 2; ++i) { + gfxTextRun* run = textFrame->GetTextRun( + (i != 0) ? nsTextFrame::eInflated : nsTextFrame::eNotInflated); + if (run) { + if (clear) { + run->ResetSizeOfAccountingFlags(); + } else { + total += run->MaybeSizeOfIncludingThis(aMallocSizeOf); + } + } + } + return total; + } + + for (const auto& childList : aFrame->ChildLists()) { + for (nsIFrame* f : childList.mList) { + total += SizeOfTextRunsForFrames(f, aMallocSizeOf, clear); + } + } + return total; +} + +/* static */ +void nsLayoutUtils::Initialize() { + nsComputedDOMStyle::RegisterPrefChangeCallbacks(); +} + +/* static */ +void nsLayoutUtils::Shutdown() { + if (sContentMap) { + sContentMap = nullptr; + } + + nsComputedDOMStyle::UnregisterPrefChangeCallbacks(); +} + +/* static */ +void nsLayoutUtils::RegisterImageRequest(nsPresContext* aPresContext, + imgIRequest* aRequest, + bool* aRequestRegistered) { + if (!aPresContext) { + return; + } + + if (aRequestRegistered && *aRequestRegistered) { + // Our request is already registered with the refresh driver, so + // no need to register it again. + return; + } + + if (aRequest) { + aPresContext->RefreshDriver()->AddImageRequest(aRequest); + if (aRequestRegistered) { + *aRequestRegistered = true; + } + } +} + +/* static */ +void nsLayoutUtils::RegisterImageRequestIfAnimated(nsPresContext* aPresContext, + imgIRequest* aRequest, + bool* aRequestRegistered) { + if (!aPresContext) { + return; + } + + if (aRequestRegistered && *aRequestRegistered) { + // Our request is already registered with the refresh driver, so + // no need to register it again. + return; + } + + if (aRequest) { + nsCOMPtr<imgIContainer> image; + if (NS_SUCCEEDED(aRequest->GetImage(getter_AddRefs(image)))) { + // Check to verify that the image is animated. If so, then add it to the + // list of images tracked by the refresh driver. + bool isAnimated = false; + nsresult rv = image->GetAnimated(&isAnimated); + if (NS_SUCCEEDED(rv) && isAnimated) { + aPresContext->RefreshDriver()->AddImageRequest(aRequest); + if (aRequestRegistered) { + *aRequestRegistered = true; + } + } + } + } +} + +/* static */ +void nsLayoutUtils::DeregisterImageRequest(nsPresContext* aPresContext, + imgIRequest* aRequest, + bool* aRequestRegistered) { + if (!aPresContext) { + return; + } + + // Deregister our imgIRequest with the refresh driver to + // complete tear-down, but only if it has been registered + if (aRequestRegistered && !*aRequestRegistered) { + return; + } + + if (aRequest) { + nsCOMPtr<imgIContainer> image; + if (NS_SUCCEEDED(aRequest->GetImage(getter_AddRefs(image)))) { + aPresContext->RefreshDriver()->RemoveImageRequest(aRequest); + + if (aRequestRegistered) { + *aRequestRegistered = false; + } + } + } +} + +/* static */ +void nsLayoutUtils::PostRestyleEvent(Element* aElement, + RestyleHint aRestyleHint, + nsChangeHint aMinChangeHint) { + if (Document* doc = aElement->GetComposedDoc()) { + if (nsPresContext* presContext = doc->GetPresContext()) { + presContext->RestyleManager()->PostRestyleEvent(aElement, aRestyleHint, + aMinChangeHint); + } + } +} + +nsSetAttrRunnable::nsSetAttrRunnable(Element* aElement, nsAtom* aAttrName, + const nsAString& aValue) + : mozilla::Runnable("nsSetAttrRunnable"), + mElement(aElement), + mAttrName(aAttrName), + mValue(aValue) { + NS_ASSERTION(aElement && aAttrName, "Missing stuff, prepare to crash"); +} + +nsSetAttrRunnable::nsSetAttrRunnable(Element* aElement, nsAtom* aAttrName, + int32_t aValue) + : mozilla::Runnable("nsSetAttrRunnable"), + mElement(aElement), + mAttrName(aAttrName) { + NS_ASSERTION(aElement && aAttrName, "Missing stuff, prepare to crash"); + mValue.AppendInt(aValue); +} + +NS_IMETHODIMP +nsSetAttrRunnable::Run() { + return mElement->SetAttr(kNameSpaceID_None, mAttrName, mValue, true); +} + +nsUnsetAttrRunnable::nsUnsetAttrRunnable(Element* aElement, nsAtom* aAttrName) + : mozilla::Runnable("nsUnsetAttrRunnable"), + mElement(aElement), + mAttrName(aAttrName) { + NS_ASSERTION(aElement && aAttrName, "Missing stuff, prepare to crash"); +} + +NS_IMETHODIMP +nsUnsetAttrRunnable::Run() { + return mElement->UnsetAttr(kNameSpaceID_None, mAttrName, true); +} + +/** + * Compute the minimum font size inside of a container with the given + * width, such that **when the user zooms the container to fill the full + * width of the device**, the fonts satisfy our minima. + */ +static nscoord MinimumFontSizeFor(nsPresContext* aPresContext, + WritingMode aWritingMode, + nscoord aContainerISize) { + PresShell* presShell = aPresContext->PresShell(); + + uint32_t emPerLine = presShell->FontSizeInflationEmPerLine(); + uint32_t minTwips = presShell->FontSizeInflationMinTwips(); + if (emPerLine == 0 && minTwips == 0) { + return 0; + } + + nscoord byLine = 0, byInch = 0; + if (emPerLine != 0) { + byLine = aContainerISize / emPerLine; + } + if (minTwips != 0) { + // REVIEW: Is this giving us app units and sizes *not* counting + // viewport scaling? + gfxSize screenSize = aPresContext->ScreenSizeInchesForFontInflation(); + float deviceISizeInches = + aWritingMode.IsVertical() ? screenSize.height : screenSize.width; + byInch = + NSToCoordRound(aContainerISize / (deviceISizeInches * 1440 / minTwips)); + } + return std::max(byLine, byInch); +} + +/* static */ +float nsLayoutUtils::FontSizeInflationInner(const nsIFrame* aFrame, + nscoord aMinFontSize) { + // Note that line heights should be inflated by the same ratio as the + // font size of the same text; thus we operate only on the font size + // even when we're scaling a line height. + nscoord styleFontSize = aFrame->StyleFont()->mFont.size.ToAppUnits(); + if (styleFontSize <= 0) { + // Never scale zero font size. + return 1.0; + } + + if (aMinFontSize <= 0) { + // No need to scale. + return 1.0; + } + + // If between this current frame and its font inflation container there is a + // non-inline element with fixed width or height, then we should not inflate + // fonts for this frame. + for (const nsIFrame* f = aFrame; f && !f->IsContainerForFontSizeInflation(); + f = f->GetParent()) { + nsIContent* content = f->GetContent(); + LayoutFrameType fType = f->Type(); + nsIFrame* parent = f->GetParent(); + // Also, if there is more than one frame corresponding to a single + // content node, we want the outermost one. + if (!(parent && parent->GetContent() == content) && + // ignore width/height on inlines since they don't apply + fType != LayoutFrameType::Inline && + // ignore width on radios and checkboxes since we enlarge them and + // they have width/height in ua.css + fType != LayoutFrameType::CheckboxRadio) { + // ruby annotations should have the same inflation as its + // grandparent, which is the ruby frame contains the annotation. + if (fType == LayoutFrameType::RubyText) { + MOZ_ASSERT(parent && parent->IsRubyTextContainerFrame()); + nsIFrame* grandparent = parent->GetParent(); + MOZ_ASSERT(grandparent && grandparent->IsRubyFrame()); + return FontSizeInflationFor(grandparent); + } + WritingMode wm = f->GetWritingMode(); + const auto& stylePosISize = f->StylePosition()->ISize(wm); + const auto& stylePosBSize = f->StylePosition()->BSize(wm); + if (!stylePosISize.IsAuto() || + !stylePosBSize.BehavesLikeInitialValueOnBlockAxis()) { + return 1.0; + } + } + } + + int32_t interceptParam = StaticPrefs::font_size_inflation_mappingIntercept(); + float maxRatio = (float)StaticPrefs::font_size_inflation_maxRatio() / 100.0f; + + float ratio = float(styleFontSize) / float(aMinFontSize); + float inflationRatio; + + // Given a minimum inflated font size m, a specified font size s, we want to + // find the inflated font size i and then return the ratio of i to s (i/s). + if (interceptParam >= 0) { + // Since the mapping intercept parameter P is greater than zero, we use it + // to determine the point where our mapping function intersects the i=s + // line. This means that we have an equation of the form: + // + // i = m + s*(P/2)/(1 + P/2), if s <= (1 + P/2)*m + // i = s, if s >= (1 + P/2)*m + + float intercept = 1 + float(interceptParam) / 2.0f; + if (ratio >= intercept) { + // If we're already at 1+P/2 or more times the minimum, don't scale. + return 1.0; + } + + // The point (intercept, intercept) is where the part of the i vs. s graph + // that's not slope 1 meets the i=s line. (This part of the + // graph is a line from (0, m), to that point). We calculate the + // intersection point to be ((1+P/2)m, (1+P/2)m), where P is the + // intercept parameter above. We then need to return i/s. + inflationRatio = (1.0f + (ratio * (intercept - 1) / intercept)) / ratio; + } else { + // This is the case where P is negative. We essentially want to implement + // the case for P=infinity here, so we make i = s + m, which means that + // i/s = s/s + m/s = 1 + 1/ratio + inflationRatio = 1 + 1.0f / ratio; + } + + if (maxRatio > 1.0 && inflationRatio > maxRatio) { + return maxRatio; + } else { + return inflationRatio; + } +} + +static bool ShouldInflateFontsForContainer(const nsIFrame* aFrame) { + // We only want to inflate fonts for text that is in a place + // with room to expand. The question is what the best heuristic for + // that is... + // For now, we're going to use NS_FRAME_IN_CONSTRAINED_BSIZE, which + // indicates whether the frame is inside something with a constrained + // block-size (propagating down the tree), but the propagation stops when + // we hit overflow-y [or -x, for vertical mode]: scroll or auto. + const nsStyleText* styleText = aFrame->StyleText(); + + return styleText->mTextSizeAdjust != StyleTextSizeAdjust::None && + !aFrame->HasAnyStateBits(NS_FRAME_IN_CONSTRAINED_BSIZE) && + // We also want to disable font inflation for containers that have + // preformatted text. + // MathML cells need special treatment. See bug 1002526 comment 56. + (styleText->WhiteSpaceCanWrap(aFrame) || + aFrame->IsFrameOfType(nsIFrame::eMathML)); +} + +nscoord nsLayoutUtils::InflationMinFontSizeFor(const nsIFrame* aFrame) { + nsPresContext* presContext = aFrame->PresContext(); + if (!FontSizeInflationEnabled(presContext) || + presContext->mInflationDisabledForShrinkWrap) { + return 0; + } + + for (const nsIFrame* f = aFrame; f; f = f->GetParent()) { + if (f->IsContainerForFontSizeInflation()) { + if (!ShouldInflateFontsForContainer(f)) { + return 0; + } + + nsFontInflationData* data = + nsFontInflationData::FindFontInflationDataFor(aFrame); + // FIXME: The need to null-check here is sort of a bug, and might + // lead to incorrect results. + if (!data || !data->InflationEnabled()) { + return 0; + } + + return MinimumFontSizeFor(aFrame->PresContext(), aFrame->GetWritingMode(), + data->UsableISize()); + } + } + + MOZ_ASSERT(false, "root should always be container"); + + return 0; +} + +float nsLayoutUtils::FontSizeInflationFor(const nsIFrame* aFrame) { + if (SVGUtils::IsInSVGTextSubtree(aFrame)) { + const nsIFrame* container = aFrame; + while (!container->IsSVGTextFrame()) { + container = container->GetParent(); + } + NS_ASSERTION(container, "expected to find an ancestor SVGTextFrame"); + return static_cast<const SVGTextFrame*>(container) + ->GetFontSizeScaleFactor(); + } + + if (!FontSizeInflationEnabled(aFrame->PresContext())) { + return 1.0f; + } + + return FontSizeInflationInner(aFrame, InflationMinFontSizeFor(aFrame)); +} + +/* static */ +bool nsLayoutUtils::FontSizeInflationEnabled(nsPresContext* aPresContext) { + PresShell* presShell = aPresContext->GetPresShell(); + if (!presShell) { + return false; + } + return presShell->FontSizeInflationEnabled(); +} + +/* static */ +nsRect nsLayoutUtils::GetBoxShadowRectForFrame(nsIFrame* aFrame, + const nsSize& aFrameSize) { + auto boxShadows = aFrame->StyleEffects()->mBoxShadow.AsSpan(); + if (boxShadows.IsEmpty()) { + return nsRect(); + } + + nsRect inputRect(nsPoint(0, 0), aFrameSize); + + // According to the CSS spec, box-shadow should be based on the border box. + // However, that looks broken when the background extends outside the border + // box, as can be the case with native theming. To fix that we expand the + // area that we shadow to include the bounds of any native theme drawing. + const nsStyleDisplay* styleDisplay = aFrame->StyleDisplay(); + nsITheme::Transparency transparency; + if (aFrame->IsThemed(styleDisplay, &transparency)) { + // For opaque (rectangular) theme widgets we can take the generic + // border-box path with border-radius disabled. + if (transparency != nsITheme::eOpaque) { + nsPresContext* presContext = aFrame->PresContext(); + presContext->Theme()->GetWidgetOverflow( + presContext->DeviceContext(), aFrame, + styleDisplay->EffectiveAppearance(), &inputRect); + } + } + + nsRect shadows; + int32_t A2D = aFrame->PresContext()->AppUnitsPerDevPixel(); + for (auto& shadow : boxShadows) { + nsRect tmpRect = inputRect; + + // inset shadows are never painted outside the frame + if (shadow.inset) { + continue; + } + + tmpRect.MoveBy(nsPoint(shadow.base.horizontal.ToAppUnits(), + shadow.base.vertical.ToAppUnits())); + tmpRect.Inflate(shadow.spread.ToAppUnits()); + tmpRect.Inflate(nsContextBoxBlur::GetBlurRadiusMargin( + shadow.base.blur.ToAppUnits(), A2D)); + shadows.UnionRect(shadows, tmpRect); + } + return shadows; +} + +/* static */ +bool nsLayoutUtils::GetContentViewerSize( + const nsPresContext* aPresContext, LayoutDeviceIntSize& aOutSize, + SubtractDynamicToolbar aSubtractDynamicToolbar) { + nsCOMPtr<nsIDocShell> docShell = aPresContext->GetDocShell(); + if (!docShell) { + return false; + } + + nsCOMPtr<nsIContentViewer> cv; + docShell->GetContentViewer(getter_AddRefs(cv)); + if (!cv) { + return false; + } + + nsIntRect bounds; + cv->GetBounds(bounds); + + if (aPresContext->IsRootContentDocumentCrossProcess() && + aSubtractDynamicToolbar == SubtractDynamicToolbar::Yes && + aPresContext->HasDynamicToolbar() && !bounds.IsEmpty()) { + MOZ_ASSERT(aPresContext->IsRootContentDocumentCrossProcess()); + bounds.height -= aPresContext->GetDynamicToolbarMaxHeight(); + // Collapse the size in the case the dynamic toolbar max height is greater + // than the content bound height so that hopefully embedders of GeckoView + // may notice they set wrong dynamic toolbar max height. + if (bounds.height < 0) { + bounds.height = 0; + } + } + + aOutSize = LayoutDeviceIntRect::FromUnknownRect(bounds).Size(); + return true; +} + +bool nsLayoutUtils::UpdateCompositionBoundsForRCDRSF( + ParentLayerRect& aCompBounds, const nsPresContext* aPresContext) { + SubtractDynamicToolbar shouldSubtractDynamicToolbar = + aPresContext->IsRootContentDocumentCrossProcess() && + aPresContext->HasDynamicToolbar() + ? SubtractDynamicToolbar::Yes + : SubtractDynamicToolbar::No; + + if (shouldSubtractDynamicToolbar == SubtractDynamicToolbar::Yes) { + if (RefPtr<MobileViewportManager> MVM = + aPresContext->PresShell()->GetMobileViewportManager()) { + CSSSize intrinsicCompositionSize = MVM->GetIntrinsicCompositionSize(); + + if (nsIScrollableFrame* rootScrollableFrame = + aPresContext->PresShell()->GetRootScrollFrameAsScrollable()) { + // Expand the composition size to include the area initially covered by + // the dynamic toolbar only if the content is taller than the intrinsic + // composition size (i.e. the dynamic toolbar should be able to move + // only if the content is vertically scrollable). + if (intrinsicCompositionSize.height < + CSSPixel::FromAppUnits( + CalculateScrollableRectForFrame(rootScrollableFrame, nullptr) + .Height())) { + shouldSubtractDynamicToolbar = SubtractDynamicToolbar::No; + } + } + } + } + + LayoutDeviceIntSize contentSize; + if (!GetContentViewerSize(aPresContext, contentSize, + shouldSubtractDynamicToolbar)) { + return false; + } + aCompBounds.SizeTo(ViewAs<ParentLayerPixel>( + LayoutDeviceSize(contentSize), + PixelCastJustification::LayoutDeviceIsParentLayerForRCDRSF)); + return true; +} + +/* static */ +nsMargin nsLayoutUtils::ScrollbarAreaToExcludeFromCompositionBoundsFor( + const nsIFrame* aScrollFrame) { + if (!aScrollFrame || !aScrollFrame->GetScrollTargetFrame()) { + return nsMargin(); + } + nsPresContext* presContext = aScrollFrame->PresContext(); + PresShell* presShell = presContext->GetPresShell(); + if (!presShell) { + return nsMargin(); + } + bool isRootScrollFrame = aScrollFrame == presShell->GetRootScrollFrame(); + bool isRootContentDocRootScrollFrame = + isRootScrollFrame && presContext->IsRootContentDocumentCrossProcess(); + if (!isRootContentDocRootScrollFrame) { + return nsMargin(); + } + if (presContext->UseOverlayScrollbars()) { + return nsMargin(); + } + nsIScrollableFrame* scrollableFrame = aScrollFrame->GetScrollTargetFrame(); + if (!scrollableFrame) { + return nsMargin(); + } + return scrollableFrame->GetActualScrollbarSizes( + nsIScrollableFrame::ScrollbarSizesOptions:: + INCLUDE_VISUAL_VIEWPORT_SCROLLBARS); +} + +/* static */ +nsSize nsLayoutUtils::CalculateCompositionSizeForFrame( + nsIFrame* aFrame, bool aSubtractScrollbars, + const nsSize* aOverrideScrollPortSize) { + // If we have a scrollable frame, restrict the composition bounds to its + // scroll port. The scroll port excludes the frame borders and the scroll + // bars, which we don't want to be part of the composition bounds. + nsIScrollableFrame* scrollableFrame = aFrame->GetScrollTargetFrame(); + nsRect rect = scrollableFrame ? scrollableFrame->GetScrollPortRect() + : aFrame->GetRect(); + nsSize size = + aOverrideScrollPortSize ? *aOverrideScrollPortSize : rect.Size(); + + nsPresContext* presContext = aFrame->PresContext(); + PresShell* presShell = presContext->PresShell(); + + bool isRootContentDocRootScrollFrame = + presContext->IsRootContentDocumentCrossProcess() && + aFrame == presShell->GetRootScrollFrame(); + if (isRootContentDocRootScrollFrame) { + ParentLayerRect compBounds; + if (UpdateCompositionBoundsForRCDRSF(compBounds, presContext)) { + int32_t auPerDevPixel = presContext->AppUnitsPerDevPixel(); + size = nsSize(compBounds.width * auPerDevPixel, + compBounds.height * auPerDevPixel); + } + } + + if (aSubtractScrollbars) { + nsMargin margins = ScrollbarAreaToExcludeFromCompositionBoundsFor(aFrame); + size.width -= margins.LeftRight(); + size.height -= margins.TopBottom(); + } + + return size; +} + +/* static */ +CSSSize nsLayoutUtils::CalculateBoundingCompositionSize( + const nsIFrame* aFrame, bool aIsRootContentDocRootScrollFrame, + const FrameMetrics& aMetrics) { + if (aIsRootContentDocRootScrollFrame) { + return ViewAs<LayerPixel>( + aMetrics.GetCompositionBounds().Size(), + PixelCastJustification::ParentLayerToLayerForRootComposition) * + LayerToScreenScale(1.0f) / aMetrics.DisplayportPixelsPerCSSPixel(); + } + nsPresContext* presContext = aFrame->PresContext(); + ScreenSize rootCompositionSize; + nsPresContext* rootPresContext = + presContext->GetInProcessRootContentDocumentPresContext(); + if (!rootPresContext) { + rootPresContext = presContext->GetRootPresContext(); + } + PresShell* rootPresShell = nullptr; + if (rootPresContext) { + rootPresShell = rootPresContext->PresShell(); + if (nsIFrame* rootFrame = rootPresShell->GetRootFrame()) { + ParentLayerRect compBounds; + if (UpdateCompositionBoundsForRCDRSF(compBounds, rootPresContext)) { + rootCompositionSize = ViewAs<ScreenPixel>( + compBounds.Size(), + PixelCastJustification::ScreenIsParentLayerForRoot); + } else { + // LayoutDeviceToScreenScale2D = + // LayoutDeviceToParentLayerScale * + // ParentLayerToScreenScale2D + LayoutDeviceToScreenScale2D cumulativeResolution = + LayoutDeviceToParentLayerScale( + rootPresShell->GetCumulativeResolution()) * + GetTransformToAncestorScaleCrossProcessForFrameMetrics(rootFrame); + + int32_t rootAUPerDevPixel = rootPresContext->AppUnitsPerDevPixel(); + rootCompositionSize = (LayoutDeviceRect::FromAppUnits( + rootFrame->GetRect(), rootAUPerDevPixel) * + cumulativeResolution) + .Size(); + } + } + } else { + nsIWidget* widget = aFrame->GetNearestWidget(); + LayoutDeviceIntRect widgetBounds = widget->GetBounds(); + rootCompositionSize = ScreenSize(ViewAs<ScreenPixel>( + widgetBounds.Size(), + PixelCastJustification::LayoutDeviceIsScreenForBounds)); + } + + // Adjust composition size for the size of scroll bars. + nsIFrame* rootRootScrollFrame = + rootPresShell ? rootPresShell->GetRootScrollFrame() : nullptr; + nsMargin scrollbarMargins = + ScrollbarAreaToExcludeFromCompositionBoundsFor(rootRootScrollFrame); + LayoutDeviceMargin margins = LayoutDeviceMargin::FromAppUnits( + scrollbarMargins, rootPresContext->AppUnitsPerDevPixel()); + // Scrollbars are not subject to resolution scaling, so LD pixels = layer + // pixels for them. + rootCompositionSize.width -= margins.LeftRight(); + rootCompositionSize.height -= margins.TopBottom(); + + CSSSize result = + rootCompositionSize / aMetrics.DisplayportPixelsPerCSSPixel(); + + // If this is a nested content process, the in-process root content document's + // composition size may still be arbitrarily large, so bound it further by + // how much of the in-process RCD is visible in the top-level (cross-process + // RCD) viewport. + if (rootPresShell) { + if (BrowserChild* bc = BrowserChild::GetFrom(rootPresShell)) { + if (const auto& visibleRect = + bc->GetTopLevelViewportVisibleRectInSelfCoords()) { + CSSSize cssVisibleRect = + visibleRect->Size() / rootPresContext->CSSToDevPixelScale(); + result = Min(result, cssVisibleRect); + } + } + } + + return result; +} + +/* static */ +nsRect nsLayoutUtils::CalculateScrollableRectForFrame( + const nsIScrollableFrame* aScrollableFrame, const nsIFrame* aRootFrame) { + nsRect contentBounds; + if (aScrollableFrame) { + contentBounds = aScrollableFrame->GetScrollRange(); + + nsPoint scrollPosition = aScrollableFrame->GetScrollPosition(); + if (aScrollableFrame->GetScrollStyles().mVertical == + StyleOverflow::Hidden) { + contentBounds.y = scrollPosition.y; + contentBounds.height = 0; + } + if (aScrollableFrame->GetScrollStyles().mHorizontal == + StyleOverflow::Hidden) { + contentBounds.x = scrollPosition.x; + contentBounds.width = 0; + } + + contentBounds.width += aScrollableFrame->GetScrollPortRect().width; + contentBounds.height += aScrollableFrame->GetScrollPortRect().height; + } else { + contentBounds = aRootFrame->GetRect(); + // Clamp to (0, 0) if there is no corresponding scrollable frame for the + // given |aRootFrame|. + contentBounds.MoveTo(0, 0); + } + return contentBounds; +} + +/* static */ +nsRect nsLayoutUtils::CalculateExpandedScrollableRect(nsIFrame* aFrame) { + nsRect scrollableRect = CalculateScrollableRectForFrame( + aFrame->GetScrollTargetFrame(), aFrame->PresShell()->GetRootFrame()); + nsSize compSize = CalculateCompositionSizeForFrame(aFrame); + + if (aFrame == aFrame->PresShell()->GetRootScrollFrame()) { + // the composition size for the root scroll frame does not include the + // local resolution, so we adjust. + float res = aFrame->PresShell()->GetResolution(); + compSize.width = NSToCoordRound(compSize.width / res); + compSize.height = NSToCoordRound(compSize.height / res); + } + + if (scrollableRect.width < compSize.width) { + scrollableRect.x = + std::max(0, scrollableRect.x - (compSize.width - scrollableRect.width)); + scrollableRect.width = compSize.width; + } + + if (scrollableRect.height < compSize.height) { + scrollableRect.y = std::max( + 0, scrollableRect.y - (compSize.height - scrollableRect.height)); + scrollableRect.height = compSize.height; + } + return scrollableRect; +} + +/* static */ +void nsLayoutUtils::DoLogTestDataForPaint(WebRenderLayerManager* aManager, + ViewID aScrollId, + const std::string& aKey, + const std::string& aValue) { + MOZ_ASSERT(nsLayoutUtils::IsAPZTestLoggingEnabled(), "don't call me"); + aManager->LogTestDataForCurrentPaint(aScrollId, aKey, aValue); +} + +void nsLayoutUtils::LogAdditionalTestData(nsDisplayListBuilder* aBuilder, + const std::string& aKey, + const std::string& aValue) { + WebRenderLayerManager* manager = aBuilder->GetWidgetLayerManager(nullptr); + if (!manager) { + return; + } + manager->LogAdditionalTestData(aKey, aValue); +} + +/* static */ +bool nsLayoutUtils::IsAPZTestLoggingEnabled() { + return StaticPrefs::apz_test_logging_enabled(); +} + +//////////////////////////////////////// +// SurfaceFromElementResult + +SurfaceFromElementResult::SurfaceFromElementResult() + // Use safe default values here + : mHadCrossOriginRedirects(false), + mIsWriteOnly(true), + mIsStillLoading(false), + mHasSize(false), + mCORSUsed(false), + mAlphaType(gfxAlphaType::Opaque) {} + +const RefPtr<mozilla::gfx::SourceSurface>& +SurfaceFromElementResult::GetSourceSurface() { + if (!mSourceSurface && mLayersImage) { + mSourceSurface = mLayersImage->GetAsSourceSurface(); + } + + return mSourceSurface; +} + +//////////////////////////////////////// + +bool nsLayoutUtils::IsNonWrapperBlock(nsIFrame* aFrame) { + MOZ_ASSERT(aFrame); + return aFrame->IsBlockFrameOrSubclass() && !aFrame->IsBlockWrapper(); +} + +bool nsLayoutUtils::NeedsPrintPreviewBackground(nsPresContext* aPresContext) { + return aPresContext->IsRootPaginatedDocument() && + (aPresContext->Type() == nsPresContext::eContext_PrintPreview || + aPresContext->Type() == nsPresContext::eContext_PageLayout); +} + +AutoMaybeDisableFontInflation::AutoMaybeDisableFontInflation(nsIFrame* aFrame) { + // FIXME: Now that inflation calculations are based on the flow + // root's NCA's (nearest common ancestor of its inflatable + // descendants) width, we could probably disable inflation in + // fewer cases than we currently do. + // MathML cells need special treatment. See bug 1002526 comment 56. + if (aFrame->IsContainerForFontSizeInflation() && + !aFrame->IsFrameOfType(nsIFrame::eMathML)) { + mPresContext = aFrame->PresContext(); + mOldValue = mPresContext->mInflationDisabledForShrinkWrap; + mPresContext->mInflationDisabledForShrinkWrap = true; + } else { + // indicate we have nothing to restore + mPresContext = nullptr; + mOldValue = false; + } +} + +AutoMaybeDisableFontInflation::~AutoMaybeDisableFontInflation() { + if (mPresContext) { + mPresContext->mInflationDisabledForShrinkWrap = mOldValue; + } +} + +namespace mozilla { + +Rect NSRectToRect(const nsRect& aRect, double aAppUnitsPerPixel) { + // Note that by making aAppUnitsPerPixel a double we're doing floating-point + // division using a larger type and avoiding rounding error. + return Rect(Float(aRect.x / aAppUnitsPerPixel), + Float(aRect.y / aAppUnitsPerPixel), + Float(aRect.width / aAppUnitsPerPixel), + Float(aRect.height / aAppUnitsPerPixel)); +} + +Rect NSRectToSnappedRect(const nsRect& aRect, double aAppUnitsPerPixel, + const gfx::DrawTarget& aSnapDT) { + // Note that by making aAppUnitsPerPixel a double we're doing floating-point + // division using a larger type and avoiding rounding error. + Rect rect(Float(aRect.x / aAppUnitsPerPixel), + Float(aRect.y / aAppUnitsPerPixel), + Float(aRect.width / aAppUnitsPerPixel), + Float(aRect.height / aAppUnitsPerPixel)); + MaybeSnapToDevicePixels(rect, aSnapDT, true); + return rect; +} +// Similar to a snapped rect, except an axis is left unsnapped if the snapping +// process results in a length of 0. +Rect NSRectToNonEmptySnappedRect(const nsRect& aRect, double aAppUnitsPerPixel, + const gfx::DrawTarget& aSnapDT) { + // Note that by making aAppUnitsPerPixel a double we're doing floating-point + // division using a larger type and avoiding rounding error. + Rect rect(Float(aRect.x / aAppUnitsPerPixel), + Float(aRect.y / aAppUnitsPerPixel), + Float(aRect.width / aAppUnitsPerPixel), + Float(aRect.height / aAppUnitsPerPixel)); + MaybeSnapToDevicePixels(rect, aSnapDT, true, false); + return rect; +} + +void StrokeLineWithSnapping(const nsPoint& aP1, const nsPoint& aP2, + int32_t aAppUnitsPerDevPixel, + DrawTarget& aDrawTarget, const Pattern& aPattern, + const StrokeOptions& aStrokeOptions, + const DrawOptions& aDrawOptions) { + Point p1 = NSPointToPoint(aP1, aAppUnitsPerDevPixel); + Point p2 = NSPointToPoint(aP2, aAppUnitsPerDevPixel); + SnapLineToDevicePixelsForStroking(p1, p2, aDrawTarget, + aStrokeOptions.mLineWidth); + aDrawTarget.StrokeLine(p1, p2, aPattern, aStrokeOptions, aDrawOptions); +} + +} // namespace mozilla + +/* static */ +void nsLayoutUtils::SetBSizeFromFontMetrics(const nsIFrame* aFrame, + ReflowOutput& aMetrics, + const LogicalMargin& aFramePadding, + WritingMode aLineWM, + WritingMode aFrameWM) { + RefPtr<nsFontMetrics> fm = + nsLayoutUtils::GetInflatedFontMetricsForFrame(aFrame); + + if (fm) { + // Compute final height of the frame. + // + // Do things the standard css2 way -- though it's hard to find it + // in the css2 spec! It's actually found in the css1 spec section + // 4.4 (you will have to read between the lines to really see + // it). + // + // The height of our box is the sum of our font size plus the top + // and bottom border and padding. The height of children do not + // affect our height. + aMetrics.SetBlockStartAscent(aLineWM.IsLineInverted() ? fm->MaxDescent() + : fm->MaxAscent()); + aMetrics.BSize(aLineWM) = fm->MaxHeight(); + } else { + NS_WARNING("Cannot get font metrics - defaulting sizes to 0"); + aMetrics.SetBlockStartAscent(aMetrics.BSize(aLineWM) = 0); + } + aMetrics.SetBlockStartAscent(aMetrics.BlockStartAscent() + + aFramePadding.BStart(aFrameWM)); + aMetrics.BSize(aLineWM) += aFramePadding.BStartEnd(aFrameWM); +} + +/* static */ +// _BOUNDARY because Dispatch() with `targets` must not handle the event. +MOZ_CAN_RUN_SCRIPT_BOUNDARY bool +nsLayoutUtils::HasDocumentLevelListenersForApzAwareEvents( + PresShell* aPresShell) { + if (Document* doc = aPresShell->GetDocument()) { + WidgetEvent event(true, eVoidEvent); + nsTArray<EventTarget*> targets; + // TODO: Bug 1506441 + nsresult rv = + EventDispatcher::Dispatch(MOZ_KnownLive(ToSupports(doc)), nullptr, + &event, nullptr, nullptr, nullptr, &targets); + NS_ENSURE_SUCCESS(rv, false); + for (size_t i = 0; i < targets.Length(); i++) { + if (targets[i]->IsApzAware()) { + return true; + } + } + } + return false; +} + +/* static */ +bool nsLayoutUtils::CanScrollOriginClobberApz(ScrollOrigin aScrollOrigin) { + switch (aScrollOrigin) { + case ScrollOrigin::None: + case ScrollOrigin::NotSpecified: + case ScrollOrigin::Apz: + case ScrollOrigin::Restore: + return false; + default: + return true; + } +} + +/* static */ +ScrollMetadata nsLayoutUtils::ComputeScrollMetadata( + const nsIFrame* aForFrame, const nsIFrame* aScrollFrame, + nsIContent* aContent, const nsIFrame* aItemFrame, + const nsPoint& aOffsetToReferenceFrame, + WebRenderLayerManager* aLayerManager, ViewID aScrollParentId, + const nsSize& aScrollPortSize, bool aIsRootContent) { + const nsPresContext* presContext = aForFrame->PresContext(); + int32_t auPerDevPixel = presContext->AppUnitsPerDevPixel(); + + PresShell* presShell = presContext->GetPresShell(); + ScrollMetadata metadata; + FrameMetrics& metrics = metadata.GetMetrics(); + metrics.SetLayoutViewport( + CSSRect(CSSPoint(), CSSSize::FromAppUnits(aScrollPortSize))); + + nsIDocShell* docShell = presContext->GetDocShell(); + const BrowsingContext* bc = + docShell ? docShell->GetBrowsingContext() : nullptr; + bool isTouchEventsEnabled = + bc && + bc->TouchEventsOverride() == mozilla::dom::TouchEventsOverride::Enabled; + + if (bc && bc->InRDMPane() && isTouchEventsEnabled) { + metadata.SetIsRDMTouchSimulationActive(true); + } + + ViewID scrollId = ScrollableLayerGuid::NULL_SCROLL_ID; + if (aContent) { + if (void* paintRequestTime = + aContent->GetProperty(nsGkAtoms::paintRequestTime)) { + metrics.SetPaintRequestTime(*static_cast<TimeStamp*>(paintRequestTime)); + aContent->RemoveProperty(nsGkAtoms::paintRequestTime); + } + scrollId = nsLayoutUtils::FindOrCreateIDFor(aContent); + nsRect dp; + if (DisplayPortUtils::GetDisplayPort(aContent, &dp)) { + metrics.SetDisplayPort(CSSRect::FromAppUnits(dp)); + DisplayPortUtils::MarkDisplayPortAsPainted(aContent); + } + + metrics.SetHasNonZeroDisplayPortMargins(false); + if (DisplayPortMarginsPropertyData* currentData = + static_cast<DisplayPortMarginsPropertyData*>( + aContent->GetProperty(nsGkAtoms::DisplayPortMargins))) { + if (currentData->mMargins.mMargins != ScreenMargin()) { + metrics.SetHasNonZeroDisplayPortMargins(true); + } + } + + // Note: GetProperty() will return nullptr both in the case where + // the property hasn't been set, and in the case where the property + // has been set to false (in which case the property value is + // `reinterpret_cast<void*>(false)` which is nullptr. + if (aContent->GetProperty(nsGkAtoms::forceMousewheelAutodir)) { + metadata.SetForceMousewheelAutodir(true); + } + + if (aContent->GetProperty(nsGkAtoms::forceMousewheelAutodirHonourRoot)) { + metadata.SetForceMousewheelAutodirHonourRoot(true); + } + + if (IsAPZTestLoggingEnabled()) { + LogTestDataForPaint(aLayerManager, scrollId, "displayport", + metrics.GetDisplayPort()); + } + + metrics.SetMinimalDisplayPort( + aContent->GetProperty(nsGkAtoms::MinimalDisplayPort)); + } + + nsIScrollableFrame* scrollableFrame = nullptr; + if (aScrollFrame) scrollableFrame = aScrollFrame->GetScrollTargetFrame(); + + metrics.SetScrollableRect( + CSSRect::FromAppUnits(nsLayoutUtils::CalculateScrollableRectForFrame( + scrollableFrame, aForFrame))); + + if (scrollableFrame) { + CSSPoint layoutScrollOffset = + CSSPoint::FromAppUnits(scrollableFrame->GetScrollPosition()); + CSSPoint visualScrollOffset = + aIsRootContent + ? CSSPoint::FromAppUnits(presShell->GetVisualViewportOffset()) + : layoutScrollOffset; + metrics.SetVisualScrollOffset(visualScrollOffset); + // APZ sometimes reads this even if we haven't set a visual scroll + // update type (specifically, in the isFirstPaint case), so always + // set it. + metrics.SetVisualDestination(visualScrollOffset); + + if (aIsRootContent) { + if (aLayerManager->GetIsFirstPaint() && + presShell->IsVisualViewportOffsetSet()) { + // Restore the visual viewport offset to the copy stored on the + // main thread. + presShell->ScrollToVisual(presShell->GetVisualViewportOffset(), + FrameMetrics::eRestore, ScrollMode::Instant); + } + } + + if (scrollableFrame->IsRootScrollFrameOfDocument()) { + if (const Maybe<PresShell::VisualScrollUpdate>& visualUpdate = + presShell->GetPendingVisualScrollUpdate()) { + metrics.SetVisualDestination( + CSSPoint::FromAppUnits(visualUpdate->mVisualScrollOffset)); + metrics.SetVisualScrollUpdateType(visualUpdate->mUpdateType); + presShell->AcknowledgePendingVisualScrollUpdate(); + } + } + + if (aIsRootContent) { + // Expand the layout viewport to the size including the area covered by + // the dynamic toolbar in the case where the dynamic toolbar is being + // used, otherwise when the dynamic toolbar transitions on the compositor, + // the layout viewport will be smaller than the visual viewport on the + // compositor, thus the layout viewport offset will be forced to be moved + // in FrameMetrics::KeepLayoutViewportEnclosingVisualViewport. + if (presContext->HasDynamicToolbar()) { + CSSRect viewport = metrics.GetLayoutViewport(); + viewport.SizeTo(nsLayoutUtils::ExpandHeightForDynamicToolbar( + presContext, viewport.Size())); + metrics.SetLayoutViewport(viewport); + + // We need to set 'fixed margins' to adjust 'fixed margins' value on the + // composiutor in the case where the dynamic toolbar is completely + // hidden because the margin value on the compositor is offset from the + // position where the dynamic toolbar is completely VISIBLE but now the + // toolbar is completely HIDDEN we need to adjust the difference on the + // compositor. + if (presContext->GetDynamicToolbarState() == + DynamicToolbarState::Collapsed) { + metrics.SetFixedLayerMargins( + ScreenMargin(0, 0, + presContext->GetDynamicToolbarHeight() - + presContext->GetDynamicToolbarMaxHeight(), + 0)); + } + } + } + + metrics.SetScrollGeneration(scrollableFrame->CurrentScrollGeneration()); + + CSSRect viewport = metrics.GetLayoutViewport(); + viewport.MoveTo(layoutScrollOffset); + metrics.SetLayoutViewport(viewport); + + nsSize lineScrollAmount = scrollableFrame->GetLineScrollAmount(); + LayoutDeviceIntSize lineScrollAmountInDevPixels = + LayoutDeviceIntSize::FromAppUnitsRounded( + lineScrollAmount, presContext->AppUnitsPerDevPixel()); + metadata.SetLineScrollAmount(lineScrollAmountInDevPixels); + + nsSize pageScrollAmount = scrollableFrame->GetPageScrollAmount(); + LayoutDeviceIntSize pageScrollAmountInDevPixels = + LayoutDeviceIntSize::FromAppUnitsRounded( + pageScrollAmount, presContext->AppUnitsPerDevPixel()); + metadata.SetPageScrollAmount(pageScrollAmountInDevPixels); + + if (aScrollFrame->GetParent()) { + metadata.SetDisregardedDirection( + WheelHandlingUtils::GetDisregardedWheelScrollDirection( + aScrollFrame->GetParent())); + } + + metadata.SetSnapInfo(scrollableFrame->GetScrollSnapInfo()); + metadata.SetOverscrollBehavior( + scrollableFrame->GetOverscrollBehaviorInfo()); + metadata.SetScrollUpdates(scrollableFrame->GetScrollUpdates()); + } + + // If we have the scrollparent being the same as the scroll id, the + // compositor-side code could get into an infinite loop while building the + // overscroll handoff chain. + MOZ_ASSERT(aScrollParentId == ScrollableLayerGuid::NULL_SCROLL_ID || + scrollId != aScrollParentId); + metrics.SetScrollId(scrollId); + metrics.SetIsRootContent(aIsRootContent); + metadata.SetScrollParentId(aScrollParentId); + + const nsIFrame* rootScrollFrame = presShell->GetRootScrollFrame(); + bool isRootScrollFrame = aScrollFrame == rootScrollFrame; + Document* document = presShell->GetDocument(); + + if (scrollId != ScrollableLayerGuid::NULL_SCROLL_ID && + !presContext->GetParentPresContext()) { + if ((aScrollFrame && isRootScrollFrame)) { + metadata.SetIsLayersIdRoot(true); + } else { + MOZ_ASSERT(document, "A non-root-scroll frame must be in a document"); + if (aContent == document->GetDocumentElement()) { + metadata.SetIsLayersIdRoot(true); + } + } + } + + // Get whether the root content is RTL(E.g. it's true either if + // "writing-mode: vertical-rl", or if + // "writing-mode: horizontal-tb; direction: rtl;" in CSS). + // For the concept of this and the reason why we need to get this kind of + // information, see the definition of |mIsAutoDirRootContentRTL| in struct + // |ScrollMetadata|. + const Element* bodyElement = document ? document->GetBodyElement() : nullptr; + const nsIFrame* primaryFrame = + bodyElement ? bodyElement->GetPrimaryFrame() : rootScrollFrame; + if (!primaryFrame) { + primaryFrame = rootScrollFrame; + } + if (primaryFrame) { + WritingMode writingModeOfRootScrollFrame = primaryFrame->GetWritingMode(); + WritingMode::BlockDir blockDirOfRootScrollFrame = + writingModeOfRootScrollFrame.GetBlockDir(); + WritingMode::InlineDir inlineDirOfRootScrollFrame = + writingModeOfRootScrollFrame.GetInlineDir(); + if (blockDirOfRootScrollFrame == WritingMode::BlockDir::eBlockRL || + (blockDirOfRootScrollFrame == WritingMode::BlockDir::eBlockTB && + inlineDirOfRootScrollFrame == WritingMode::InlineDir::eInlineRTL)) { + metadata.SetIsAutoDirRootContentRTL(true); + } + } + + // Only the root scrollable frame for a given presShell should pick up + // the presShell's resolution. All the other frames are 1.0. + if (isRootScrollFrame) { + metrics.SetPresShellResolution(presShell->GetResolution()); + } else { + metrics.SetPresShellResolution(1.0f); + } + + if (presShell->IsResolutionUpdated()) { + metadata.SetResolutionUpdated(true); + } + + // The cumulative resolution is the resolution at which the scroll frame's + // content is actually rendered. It includes the pres shell resolutions of + // all the pres shells from here up to the root, as well as any css-driven + // resolution. We don't need to compute it as it's already stored in the + // container parameters... except if we're in WebRender in which case we + // don't have a aContainerParameters. In that case we're also not rasterizing + // in Gecko anyway, so the only resolution we care about here is the presShell + // resolution which we need to propagate to WebRender. + metrics.SetCumulativeResolution( + LayoutDeviceToLayerScale(presShell->GetCumulativeResolution())); + + metrics.SetTransformToAncestorScale( + GetTransformToAncestorScaleCrossProcessForFrameMetrics( + aScrollFrame ? aScrollFrame : aForFrame)); + metrics.SetDevPixelsPerCSSPixel(presContext->CSSToDevPixelScale()); + + // Initially, AsyncPanZoomController should render the content to the screen + // at the painted resolution. + const LayerToParentLayerScale layerToParentLayerScale(1.0f); + metrics.SetZoom(metrics.GetCumulativeResolution() * + metrics.GetDevPixelsPerCSSPixel() * layerToParentLayerScale); + + // Calculate the composition bounds as the size of the scroll frame and + // its origin relative to the reference frame. + // If aScrollFrame is null, we are in a document without a root scroll frame, + // so it's a xul document. In this case, use the size of the viewport frame. + const nsIFrame* frameForCompositionBoundsCalculation = + aScrollFrame ? aScrollFrame : aForFrame; + nsRect compositionBounds( + frameForCompositionBoundsCalculation->GetOffsetToCrossDoc(aItemFrame) + + aOffsetToReferenceFrame, + frameForCompositionBoundsCalculation->GetSize()); + if (scrollableFrame) { + // If we have a scrollable frame, restrict the composition bounds to its + // scroll port. The scroll port excludes the frame borders and the scroll + // bars, which we don't want to be part of the composition bounds. + nsRect scrollPort = scrollableFrame->GetScrollPortRect(); + compositionBounds = nsRect( + compositionBounds.TopLeft() + scrollPort.TopLeft(), scrollPort.Size()); + } + ParentLayerRect frameBounds = + LayoutDeviceRect::FromAppUnits(compositionBounds, auPerDevPixel) * + metrics.GetCumulativeResolution() * layerToParentLayerScale; + + // For the root scroll frame of the root content document (RCD-RSF), the above + // calculation will yield the size of the viewport frame as the composition + // bounds, which doesn't actually correspond to what is visible when + // nsIDOMWindowUtils::setCSSViewport has been called to modify the visible + // area of the prescontext that the viewport frame is reflowed into. In that + // case if our document has a widget then the widget's bounds will correspond + // to what is visible. If we don't have a widget the root view's bounds + // correspond to what would be visible because they don't get modified by + // setCSSViewport. + bool isRootContentDocRootScrollFrame = + isRootScrollFrame && presContext->IsRootContentDocumentCrossProcess(); + if (isRootContentDocRootScrollFrame) { + UpdateCompositionBoundsForRCDRSF(frameBounds, presContext); + if (RefPtr<MobileViewportManager> MVM = + presContext->PresShell()->GetMobileViewportManager()) { + metrics.SetCompositionSizeWithoutDynamicToolbar( + MVM->GetCompositionSizeWithoutDynamicToolbar()); + } + } + + metrics.SetCompositionBoundsWidthIgnoringScrollbars(frameBounds.width); + + nsMargin sizes = ScrollbarAreaToExcludeFromCompositionBoundsFor(aScrollFrame); + // Scrollbars are not subject to resolution scaling, so LD pixels = layer + // pixels for them. + ParentLayerMargin boundMargins = + LayoutDeviceMargin::FromAppUnits(sizes, auPerDevPixel) * + LayoutDeviceToParentLayerScale(1.0f); + frameBounds.Deflate(boundMargins); + + metrics.SetCompositionBounds(frameBounds); + + metrics.SetBoundingCompositionSize( + nsLayoutUtils::CalculateBoundingCompositionSize( + aScrollFrame ? aScrollFrame : aForFrame, + isRootContentDocRootScrollFrame, metrics)); + + if (StaticPrefs::apz_printtree() || StaticPrefs::apz_test_logging_enabled()) { + if (const nsIContent* content = + frameForCompositionBoundsCalculation->GetContent()) { + nsAutoString contentDescription; + if (content->IsElement()) { + content->AsElement()->Describe(contentDescription); + } else { + contentDescription.AssignLiteral("(not an element)"); + } + metadata.SetContentDescription( + NS_LossyConvertUTF16toASCII(contentDescription)); + if (IsAPZTestLoggingEnabled()) { + LogTestDataForPaint(aLayerManager, scrollId, "contentDescription", + metadata.GetContentDescription().get()); + } + } + } + + metrics.SetPresShellId(presShell->GetPresShellId()); + + // If the scroll frame's content is marked 'scrollgrab', record this + // in the FrameMetrics so APZ knows to provide the scroll grabbing + // behaviour. + if (aScrollFrame && + nsContentUtils::HasScrollgrab(aScrollFrame->GetContent())) { + metadata.SetHasScrollgrab(true); + } + + // Also compute and set the background color. + // This is needed for APZ overscrolling support. + if (aScrollFrame) { + if (isRootScrollFrame) { + metadata.SetBackgroundColor( + sRGBColor::FromABGR(presShell->GetCanvasBackground())); + } else if (const auto* backgroundStyle = + nsCSSRendering::FindBackground(aScrollFrame)) { + nscolor backgroundColor = + backgroundStyle->StyleBackground()->BackgroundColor(backgroundStyle); + metadata.SetBackgroundColor(sRGBColor::FromABGR(backgroundColor)); + } + } + + if (ShouldDisableApzForElement(aContent)) { + metadata.SetForceDisableApz(true); + } + + metadata.SetIsPaginatedPresentation(presContext->Type() != + nsPresContext::eContext_Galley); + + return metadata; +} + +/*static*/ +Maybe<ScrollMetadata> nsLayoutUtils::GetRootMetadata( + nsDisplayListBuilder* aBuilder, WebRenderLayerManager* aLayerManager, + const std::function<bool(ViewID& aScrollId)>& aCallback) { + nsIFrame* frame = aBuilder->RootReferenceFrame(); + nsPresContext* presContext = frame->PresContext(); + PresShell* presShell = presContext->PresShell(); + Document* document = presShell->GetDocument(); + + // There is one case where we want the root container layer to have metrics. + // If the parent process is using XUL windows, there is no root scrollframe, + // and without explicitly creating metrics there will be no guaranteed + // top-level APZC. + bool addMetrics = XRE_IsParentProcess() && !presShell->GetRootScrollFrame(); + + // Add metrics if there are none in the layer tree with the id (create an id + // if there isn't one already) of the root scroll frame/root content. + bool ensureMetricsForRootId = nsLayoutUtils::AsyncPanZoomEnabled(frame) && + aBuilder->IsPaintingToWindow() && + !presContext->GetParentPresContext(); + + nsIContent* content = nullptr; + nsIFrame* rootScrollFrame = presShell->GetRootScrollFrame(); + if (rootScrollFrame) { + content = rootScrollFrame->GetContent(); + } else { + // If there is no root scroll frame, pick the document element instead. + // The only case we don't want to do this is in non-APZ fennec, where + // we want the root xul document to get a null scroll id so that the root + // content document gets the first non-null scroll id. + content = document->GetDocumentElement(); + } + + if (ensureMetricsForRootId && content) { + ViewID scrollId = nsLayoutUtils::FindOrCreateIDFor(content); + if (aCallback(scrollId)) { + ensureMetricsForRootId = false; + } + } + + if (addMetrics || ensureMetricsForRootId) { + bool isRootContent = presContext->IsRootContentDocumentCrossProcess(); + + nsSize scrollPortSize = frame->GetSize(); + if (isRootContent && rootScrollFrame) { + nsIScrollableFrame* scrollableFrame = + rootScrollFrame->GetScrollTargetFrame(); + scrollPortSize = scrollableFrame->GetScrollPortRect().Size(); + } + return Some(nsLayoutUtils::ComputeScrollMetadata( + frame, rootScrollFrame, content, frame, + aBuilder->ToReferenceFrame(frame), aLayerManager, + ScrollableLayerGuid::NULL_SCROLL_ID, scrollPortSize, isRootContent)); + } + + return Nothing(); +} + +/* static */ +void nsLayoutUtils::TransformToAncestorAndCombineRegions( + const nsRegion& aRegion, nsIFrame* aFrame, const nsIFrame* aAncestorFrame, + nsRegion* aPreciseTargetDest, nsRegion* aImpreciseTargetDest, + Maybe<Matrix4x4Flagged>* aMatrixCache, const DisplayItemClip* aClip) { + if (aRegion.IsEmpty()) { + return; + } + bool isPrecise; + RegionBuilder<nsRegion> transformedRegion; + for (nsRegion::RectIterator it = aRegion.RectIter(); !it.Done(); it.Next()) { + nsRect transformed = TransformFrameRectToAncestor( + aFrame, it.Get(), aAncestorFrame, &isPrecise, aMatrixCache); + if (aClip) { + transformed = aClip->ApplyNonRoundedIntersection(transformed); + if (aClip->GetRoundedRectCount() > 0) { + isPrecise = false; + } + } + transformedRegion.OrWith(transformed); + } + nsRegion* dest = isPrecise ? aPreciseTargetDest : aImpreciseTargetDest; + dest->OrWith(transformedRegion.ToRegion()); + // If the region becomes too complex this has a large performance impact. + // We limit its complexity here. + if (dest->GetNumRects() > 12) { + dest->SimplifyOutward(6); + if (isPrecise) { + aPreciseTargetDest->OrWith(*aImpreciseTargetDest); + *aImpreciseTargetDest = std::move(*aPreciseTargetDest); + aImpreciseTargetDest->SimplifyOutward(6); + *aPreciseTargetDest = nsRegion(); + } + } +} + +/* static */ +bool nsLayoutUtils::ShouldUseNoScriptSheet(Document* aDocument) { + // also handle the case where print is done from print preview + // see bug #342439 for more details + if (aDocument->IsStaticDocument()) { + aDocument = aDocument->GetOriginalDocument(); + } + return aDocument->IsScriptEnabled(); +} + +/* static */ +bool nsLayoutUtils::ShouldUseNoFramesSheet(Document* aDocument) { + bool allowSubframes = true; + nsIDocShell* docShell = aDocument->GetDocShell(); + if (docShell) { + docShell->GetAllowSubframes(&allowSubframes); + } + return !allowSubframes; +} + +/* static */ +void nsLayoutUtils::GetFrameTextContent(nsIFrame* aFrame, nsAString& aResult) { + aResult.Truncate(); + AppendFrameTextContent(aFrame, aResult); +} + +/* static */ +void nsLayoutUtils::AppendFrameTextContent(nsIFrame* aFrame, + nsAString& aResult) { + if (aFrame->IsTextFrame()) { + auto* const textFrame = static_cast<nsTextFrame*>(aFrame); + const auto offset = AssertedCast<uint32_t>(textFrame->GetContentOffset()); + const auto length = AssertedCast<uint32_t>(textFrame->GetContentLength()); + textFrame->TextFragment()->AppendTo(aResult, offset, length); + } else { + for (nsIFrame* child : aFrame->PrincipalChildList()) { + AppendFrameTextContent(child, aResult); + } + } +} + +/* static */ +nsRect nsLayoutUtils::GetSelectionBoundingRect(const Selection* aSel) { + nsRect res; + // Bounding client rect may be empty after calling GetBoundingClientRect + // when range is collapsed. So we get caret's rect when range is + // collapsed. + if (aSel->IsCollapsed()) { + nsIFrame* frame = nsCaret::GetGeometry(aSel, &res); + if (frame) { + nsIFrame* relativeTo = GetContainingBlockForClientRect(frame); + res = TransformFrameRectToAncestor(frame, res, relativeTo); + } + } else { + RectAccumulator accumulator; + const uint32_t rangeCount = aSel->RangeCount(); + for (const uint32_t idx : IntegerRange(rangeCount)) { + MOZ_ASSERT(aSel->RangeCount() == rangeCount); + nsRange* range = aSel->GetRangeAt(idx); + nsRange::CollectClientRectsAndText( + &accumulator, nullptr, range, range->GetStartContainer(), + range->StartOffset(), range->GetEndContainer(), range->EndOffset(), + true, false); + } + res = accumulator.mResultRect.IsEmpty() ? accumulator.mFirstRect + : accumulator.mResultRect; + } + + return res; +} + +/* static */ +nsBlockFrame* nsLayoutUtils::GetFloatContainingBlock(nsIFrame* aFrame) { + nsIFrame* ancestor = aFrame->GetParent(); + while (ancestor && !ancestor->IsFloatContainingBlock()) { + ancestor = ancestor->GetParent(); + } + MOZ_ASSERT(!ancestor || ancestor->IsBlockFrameOrSubclass(), + "Float containing block can only be block frame"); + return static_cast<nsBlockFrame*>(ancestor); +} + +// The implementations of this calculation are adapted from +// Element::GetBoundingClientRect(). +/* static */ +CSSRect nsLayoutUtils::GetBoundingContentRect( + const nsIContent* aContent, const nsIScrollableFrame* aRootScrollFrame, + Maybe<CSSRect>* aOutNearestScrollClip) { + if (nsIFrame* frame = aContent->GetPrimaryFrame()) { + return GetBoundingFrameRect(frame, aRootScrollFrame, aOutNearestScrollClip); + } + return CSSRect(); +} + +/* static */ +CSSRect nsLayoutUtils::GetBoundingFrameRect( + nsIFrame* aFrame, const nsIScrollableFrame* aRootScrollFrame, + Maybe<CSSRect>* aOutNearestScrollClip) { + CSSRect result; + nsIFrame* relativeTo = aRootScrollFrame->GetScrolledFrame(); + result = CSSRect::FromAppUnits(nsLayoutUtils::GetAllInFlowRectsUnion( + aFrame, relativeTo, nsLayoutUtils::RECTS_ACCOUNT_FOR_TRANSFORMS)); + + // If the element is contained in a scrollable frame that is not + // the root scroll frame, make sure to clip the result so that it is + // not larger than the containing scrollable frame's bounds. + nsIScrollableFrame* scrollFrame = nsLayoutUtils::GetNearestScrollableFrame( + aFrame, SCROLLABLE_INCLUDE_HIDDEN | SCROLLABLE_FIXEDPOS_FINDS_ROOT); + if (scrollFrame && scrollFrame != aRootScrollFrame) { + nsIFrame* subFrame = do_QueryFrame(scrollFrame); + MOZ_ASSERT(subFrame); + // Get the bounds of the scroll frame in the same coordinate space + // as |result|. + nsRect subFrameRect = subFrame->GetRectRelativeToSelf(); + TransformResult res = + nsLayoutUtils::TransformRect(subFrame, relativeTo, subFrameRect); + MOZ_ASSERT(res == TRANSFORM_SUCCEEDED || res == NONINVERTIBLE_TRANSFORM); + if (res == TRANSFORM_SUCCEEDED) { + CSSRect subFrameRectCSS = CSSRect::FromAppUnits(subFrameRect); + if (aOutNearestScrollClip) { + *aOutNearestScrollClip = Some(subFrameRectCSS); + } + + result = subFrameRectCSS.Intersect(result); + } + } + return result; +} + +/* static */ +bool nsLayoutUtils::IsTransformed(nsIFrame* aForFrame, nsIFrame* aTopFrame) { + for (nsIFrame* f = aForFrame; f != aTopFrame; f = f->GetParent()) { + if (f->IsTransformed()) { + return true; + } + } + return false; +} + +/*static*/ +CSSPoint nsLayoutUtils::GetCumulativeApzCallbackTransform(nsIFrame* aFrame) { + CSSPoint delta; + if (!aFrame) { + return delta; + } + nsIFrame* frame = aFrame; + nsCOMPtr<nsIContent> lastContent; + bool seenRcdRsf = false; + + // Helper lambda to apply the callback transform for a single frame. + auto applyCallbackTransformForFrame = [&](nsIFrame* frame) { + if (frame) { + nsCOMPtr<nsIContent> content = frame->GetContent(); + if (content && (content != lastContent)) { + void* property = content->GetProperty(nsGkAtoms::apzCallbackTransform); + if (property) { + delta += *static_cast<CSSPoint*>(property); + } + } + lastContent = content; + } + }; + + while (frame) { + // Apply the callback transform for the current frame. + applyCallbackTransformForFrame(frame); + + // Keep track of whether we've encountered the RCD-RSF's content element. + nsPresContext* pc = frame->PresContext(); + if (pc->IsRootContentDocumentCrossProcess()) { + if (PresShell* shell = pc->GetPresShell()) { + if (nsIFrame* rsf = shell->GetRootScrollFrame()) { + if (frame->GetContent() == rsf->GetContent()) { + seenRcdRsf = true; + } + } + } + } + + // If we reach the RCD's viewport frame, but have not encountered + // the RCD-RSF, we were inside fixed content in the RCD. + // We still want to apply the RCD-RSF's callback transform because + // it contains the offset between the visual and layout viewports + // which applies to fixed content as well. + ViewportFrame* viewportFrame = do_QueryFrame(frame); + if (viewportFrame) { + if (pc->IsRootContentDocumentCrossProcess() && !seenRcdRsf) { + applyCallbackTransformForFrame(pc->PresShell()->GetRootScrollFrame()); + } + } + + // Proceed to the parent frame. + frame = GetCrossDocParentFrameInProcess(frame); + } + return delta; +} + +static nsSize ComputeMaxSizeForPartialPrerender(nsIFrame* aFrame, + nsSize aMaxSize) { + Matrix4x4Flagged transform = nsLayoutUtils::GetTransformToAncestor( + RelativeTo{aFrame}, + RelativeTo{nsLayoutUtils::GetDisplayRootFrame(aFrame)}); + + Matrix transform2D; + if (!transform.Is2D(&transform2D)) { + return aMaxSize; + } + + gfx::Rect result(0, 0, aMaxSize.width, aMaxSize.height); + auto scale = transform2D.ScaleFactors(); + if (scale.xScale != 0 && scale.yScale != 0) { + result.width /= scale.xScale; + result.height /= scale.yScale; + } + + // Don't apply translate. + transform2D._31 = 0.0f; + transform2D._32 = 0.0f; + + // Don't apply scale. + if (scale.xScale != 0 && scale.yScale != 0) { + transform2D._11 /= scale.xScale; + transform2D._12 /= scale.xScale; + transform2D._21 /= scale.yScale; + transform2D._22 /= scale.yScale; + } + + // Theoretically we should use transform2D.Inverse() here but in this case + // |transform2D| is a pure rotation matrix, no scaling, no translate at all, + // so that the result bound's width and height would be pretty much same + // as the one rotated by the inverse matrix. + result = transform2D.TransformBounds(result); + return nsSize( + result.width < (float)nscoord_MAX ? result.width : nscoord_MAX, + result.height < (float)nscoord_MAX ? result.height : nscoord_MAX); +} + +/* static */ +nsRect nsLayoutUtils::ComputePartialPrerenderArea( + nsIFrame* aFrame, const nsRect& aDirtyRect, const nsRect& aOverflow, + const nsSize& aPrerenderSize) { + nsSize maxSizeForPartialPrerender = + ComputeMaxSizeForPartialPrerender(aFrame, aPrerenderSize); + // Simple calculation for now: center the pre-render area on the dirty rect, + // and clamp to the overflow area. Later we can do more advanced things like + // redistributing from one axis to another, or from one side to another. + nscoord xExcess = + std::max(maxSizeForPartialPrerender.width - aDirtyRect.width, 0); + nscoord yExcess = + std::max(maxSizeForPartialPrerender.height - aDirtyRect.height, 0); + nsRect result = aDirtyRect; + result.Inflate(xExcess / 2, yExcess / 2); + return result.MoveInsideAndClamp(aOverflow); +} + +static bool LineHasNonEmptyContentWorker(nsIFrame* aFrame) { + // Look for non-empty frames, but ignore inline and br frames. + // For inline frames, descend into the children, if any. + if (aFrame->IsInlineFrame()) { + for (nsIFrame* child : aFrame->PrincipalChildList()) { + if (LineHasNonEmptyContentWorker(child)) { + return true; + } + } + } else { + if (!aFrame->IsBrFrame() && !aFrame->IsEmpty()) { + return true; + } + } + return false; +} + +static bool LineHasNonEmptyContent(nsLineBox* aLine) { + int32_t count = aLine->GetChildCount(); + for (nsIFrame* frame = aLine->mFirstChild; count > 0; + --count, frame = frame->GetNextSibling()) { + if (LineHasNonEmptyContentWorker(frame)) { + return true; + } + } + return false; +} + +/* static */ +bool nsLayoutUtils::IsInvisibleBreak(nsINode* aNode, + nsIFrame** aNextLineFrame) { + if (aNextLineFrame) { + *aNextLineFrame = nullptr; + } + + if (!aNode->IsElement() || !aNode->IsEditable()) { + return false; + } + nsIFrame* frame = aNode->AsElement()->GetPrimaryFrame(); + if (!frame || !frame->IsBrFrame()) { + return false; + } + + nsContainerFrame* f = frame->GetParent(); + while (f && f->IsFrameOfType(nsIFrame::eLineParticipant)) { + f = f->GetParent(); + } + nsBlockFrame* blockAncestor = do_QueryFrame(f); + if (!blockAncestor) { + // The container frame doesn't support line breaking. + return false; + } + + bool valid = false; + nsBlockInFlowLineIterator iter(blockAncestor, frame, &valid); + if (!valid) { + return false; + } + + bool lineNonEmpty = LineHasNonEmptyContent(iter.GetLine()); + if (!lineNonEmpty) { + return false; + } + + while (iter.Next()) { + auto currentLine = iter.GetLine(); + // Completely skip empty lines. + if (!currentLine->IsEmpty()) { + // If we come across an inline line, the BR has caused a visible line + // break. + if (currentLine->IsInline()) { + if (aNextLineFrame) { + *aNextLineFrame = currentLine->mFirstChild; + } + return false; + } + break; + } + } + + return lineNonEmpty; +} + +static nsRect ComputeSVGReferenceRect(nsIFrame* aFrame, + StyleGeometryBox aGeometryBox) { + MOZ_ASSERT(aFrame->GetContent()->IsSVGElement()); + nsRect r; + + // For SVG elements without associated CSS layout box, the used value for + // content-box, padding-box, border-box and margin-box is fill-box. + switch (aGeometryBox) { + case StyleGeometryBox::StrokeBox: { + // XXX Bug 1299876 + // The size of stroke-box is not correct if this graphic element has + // specific stroke-linejoin or stroke-linecap. + gfxRect bbox = + SVGUtils::GetBBox(aFrame, SVGUtils::eBBoxIncludeFillGeometry | + SVGUtils::eBBoxIncludeStroke); + r = nsLayoutUtils::RoundGfxRectToAppRect(bbox, AppUnitsPerCSSPixel()); + break; + } + case StyleGeometryBox::ViewBox: { + SVGViewportElement* viewportElement = + SVGElement::FromNode(aFrame->GetContent())->GetCtx(); + if (!viewportElement) { + // We should not render without a viewport so return an empty rect. + break; + } + + if (viewportElement->HasViewBox()) { + // If a `viewBox` attribute is specified for the SVG viewport creating + // element: + // 1. The reference box is positioned at the origin of the coordinate + // system established by the `viewBox` attribute. + // 2. The dimension of the reference box is set to the width and height + // values of the `viewBox` attribute. + const SVGViewBox& value = + viewportElement->GetAnimatedViewBox()->GetAnimValue(); + r = nsRect(nsPresContext::CSSPixelsToAppUnits(value.x), + nsPresContext::CSSPixelsToAppUnits(value.y), + nsPresContext::CSSPixelsToAppUnits(value.width), + nsPresContext::CSSPixelsToAppUnits(value.height)); + } else { + // No viewBox is specified, uses the nearest SVG viewport as reference + // box. + svgFloatSize viewportSize = viewportElement->GetViewportSize(); + r = nsRect(0, 0, nsPresContext::CSSPixelsToAppUnits(viewportSize.width), + nsPresContext::CSSPixelsToAppUnits(viewportSize.height)); + } + + break; + } + case StyleGeometryBox::NoBox: + case StyleGeometryBox::BorderBox: + case StyleGeometryBox::ContentBox: + case StyleGeometryBox::PaddingBox: + case StyleGeometryBox::MarginBox: + case StyleGeometryBox::FillBox: { + gfxRect bbox = + SVGUtils::GetBBox(aFrame, SVGUtils::eBBoxIncludeFillGeometry); + r = nsLayoutUtils::RoundGfxRectToAppRect(bbox, AppUnitsPerCSSPixel()); + break; + } + default: { + MOZ_ASSERT_UNREACHABLE("unknown StyleGeometryBox type"); + gfxRect bbox = + SVGUtils::GetBBox(aFrame, SVGUtils::eBBoxIncludeFillGeometry); + r = nsLayoutUtils::RoundGfxRectToAppRect(bbox, AppUnitsPerCSSPixel()); + break; + } + } + + return r; +} + +static nsRect ComputeHTMLReferenceRect(nsIFrame* aFrame, + StyleGeometryBox aGeometryBox) { + nsRect r; + + // For elements with associated CSS layout box, the used value for fill-box, + // stroke-box and view-box is border-box. + switch (aGeometryBox) { + case StyleGeometryBox::ContentBox: + r = aFrame->GetContentRectRelativeToSelf(); + break; + case StyleGeometryBox::PaddingBox: + r = aFrame->GetPaddingRectRelativeToSelf(); + break; + case StyleGeometryBox::MarginBox: + r = aFrame->GetMarginRectRelativeToSelf(); + break; + case StyleGeometryBox::NoBox: + case StyleGeometryBox::BorderBox: + case StyleGeometryBox::FillBox: + case StyleGeometryBox::StrokeBox: + case StyleGeometryBox::ViewBox: + r = aFrame->GetRectRelativeToSelf(); + break; + default: + MOZ_ASSERT_UNREACHABLE("unknown StyleGeometryBox type"); + r = aFrame->GetRectRelativeToSelf(); + break; + } + + return r; +} + +static StyleGeometryBox ShapeBoxToGeometryBox(const StyleShapeBox& aBox) { + switch (aBox) { + case StyleShapeBox::BorderBox: + return StyleGeometryBox::BorderBox; + case StyleShapeBox::ContentBox: + return StyleGeometryBox::ContentBox; + case StyleShapeBox::MarginBox: + return StyleGeometryBox::MarginBox; + case StyleShapeBox::PaddingBox: + return StyleGeometryBox::PaddingBox; + } + MOZ_ASSERT_UNREACHABLE("Unknown shape box type"); + return StyleGeometryBox::MarginBox; +} + +static StyleGeometryBox ClipPathBoxToGeometryBox( + const StyleShapeGeometryBox& aBox) { + using Tag = StyleShapeGeometryBox::Tag; + switch (aBox.tag) { + case Tag::ShapeBox: + return ShapeBoxToGeometryBox(aBox.AsShapeBox()); + case Tag::ElementDependent: + return StyleGeometryBox::NoBox; + case Tag::FillBox: + return StyleGeometryBox::FillBox; + case Tag::StrokeBox: + return StyleGeometryBox::StrokeBox; + case Tag::ViewBox: + return StyleGeometryBox::ViewBox; + } + MOZ_ASSERT_UNREACHABLE("Unknown shape box type"); + return StyleGeometryBox::NoBox; +} + +/* static */ +nsRect nsLayoutUtils::ComputeGeometryBox(nsIFrame* aFrame, + StyleGeometryBox aGeometryBox) { + // We use ComputeSVGReferenceRect for all SVG elements, except <svg> + // element, which does have an associated CSS layout box. In this case we + // should still use ComputeHTMLReferenceRect for region computing. + return aFrame->HasAnyStateBits(NS_FRAME_SVG_LAYOUT) + ? ComputeSVGReferenceRect(aFrame, aGeometryBox) + : ComputeHTMLReferenceRect(aFrame, aGeometryBox); +} + +nsRect nsLayoutUtils::ComputeGeometryBox(nsIFrame* aFrame, + const StyleShapeBox& aBox) { + return ComputeGeometryBox(aFrame, ShapeBoxToGeometryBox(aBox)); +} + +nsRect nsLayoutUtils::ComputeGeometryBox(nsIFrame* aFrame, + const StyleShapeGeometryBox& aBox) { + return ComputeGeometryBox(aFrame, ClipPathBoxToGeometryBox(aBox)); +} + +/* static */ +nsPoint nsLayoutUtils::ComputeOffsetToUserSpace(nsDisplayListBuilder* aBuilder, + nsIFrame* aFrame) { + nsPoint offsetToBoundingBox = + aBuilder->ToReferenceFrame(aFrame) - + SVGIntegrationUtils::GetOffsetToBoundingBox(aFrame); + if (!aFrame->IsFrameOfType(nsIFrame::eSVG)) { + // Snap the offset if the reference frame is not a SVG frame, since other + // frames will be snapped to pixel when rendering. + offsetToBoundingBox = + nsPoint(aFrame->PresContext()->RoundAppUnitsToNearestDevPixels( + offsetToBoundingBox.x), + aFrame->PresContext()->RoundAppUnitsToNearestDevPixels( + offsetToBoundingBox.y)); + } + + // During SVG painting, the offset computed here is applied to the gfxContext + // "ctx" used to paint the mask. After applying only "offsetToBoundingBox", + // "ctx" would have its origin at the top left corner of frame's bounding box + // (over all continuations). + // However, SVG painting needs the origin to be located at the origin of the + // SVG frame's "user space", i.e. the space in which, for example, the + // frame's BBox lives. + // SVG geometry frames and foreignObject frames apply their own offsets, so + // their position is relative to their user space. So for these frame types, + // if we want "ctx" to be in user space, we first need to subtract the + // frame's position so that SVG painting can later add it again and the + // frame is painted in the right place. + gfxPoint toUserSpaceGfx = + SVGUtils::FrameSpaceInCSSPxToUserSpaceOffset(aFrame); + nsPoint toUserSpace = + nsPoint(nsPresContext::CSSPixelsToAppUnits(float(toUserSpaceGfx.x)), + nsPresContext::CSSPixelsToAppUnits(float(toUserSpaceGfx.y))); + + return (offsetToBoundingBox - toUserSpace); +} + +/* static */ +already_AddRefed<nsFontMetrics> nsLayoutUtils::GetMetricsFor( + nsPresContext* aPresContext, bool aIsVertical, + const nsStyleFont* aStyleFont, Length aFontSize, bool aUseUserFontSet) { + nsFont font = aStyleFont->mFont; + font.size = aFontSize; + gfxFont::Orientation orientation = + aIsVertical ? nsFontMetrics::eVertical : nsFontMetrics::eHorizontal; + nsFontMetrics::Params params; + params.language = aStyleFont->mLanguage; + params.explicitLanguage = aStyleFont->mExplicitLanguage; + params.orientation = orientation; + params.userFontSet = + aUseUserFontSet ? aPresContext->GetUserFontSet() : nullptr; + params.textPerf = aPresContext->GetTextPerfMetrics(); + params.featureValueLookup = aPresContext->GetFontFeatureValuesLookup(); + return aPresContext->GetMetricsFor(font, params); +} + +/* static */ +void nsLayoutUtils::ComputeSystemFont(nsFont* aSystemFont, + LookAndFeel::FontID aFontID, + const nsFont& aDefaultVariableFont, + const Document* aDocument) { + gfxFontStyle fontStyle; + nsAutoString systemFontName; + if (!LookAndFeel::GetFont(aFontID, systemFontName, fontStyle)) { + return; + } + systemFontName.Trim("\"'"); + NS_ConvertUTF16toUTF8 nameu8(systemFontName); + Servo_FontFamily_ForSystemFont(&nameu8, &aSystemFont->family); + aSystemFont->style = fontStyle.style; + aSystemFont->family.is_system_font = fontStyle.systemFont; + aSystemFont->weight = fontStyle.weight; + aSystemFont->stretch = fontStyle.stretch; + aSystemFont->size = Length::FromPixels(fontStyle.size); + + // aSystemFont->langGroup = fontStyle.langGroup; + switch (StyleFontSizeAdjust::Tag(fontStyle.sizeAdjustBasis)) { + case StyleFontSizeAdjust::Tag::None: + aSystemFont->sizeAdjust = StyleFontSizeAdjust::None(); + break; + case StyleFontSizeAdjust::Tag::ExHeight: + aSystemFont->sizeAdjust = + StyleFontSizeAdjust::ExHeight(fontStyle.sizeAdjust); + break; + case StyleFontSizeAdjust::Tag::CapHeight: + aSystemFont->sizeAdjust = + StyleFontSizeAdjust::CapHeight(fontStyle.sizeAdjust); + break; + case StyleFontSizeAdjust::Tag::ChWidth: + aSystemFont->sizeAdjust = + StyleFontSizeAdjust::ChWidth(fontStyle.sizeAdjust); + break; + case StyleFontSizeAdjust::Tag::IcWidth: + aSystemFont->sizeAdjust = + StyleFontSizeAdjust::IcWidth(fontStyle.sizeAdjust); + break; + case StyleFontSizeAdjust::Tag::IcHeight: + aSystemFont->sizeAdjust = + StyleFontSizeAdjust::IcHeight(fontStyle.sizeAdjust); + break; + } + + if (aFontID == LookAndFeel::FontID::MozField || + aFontID == LookAndFeel::FontID::MozButton || + aFontID == LookAndFeel::FontID::MozList) { + // For textfields, buttons and selects, we use whatever font is defined by + // the system. Which it appears (and the assumption is) it is always a + // proportional font. Then we always use 2 points smaller than what the + // browser has defined as the default proportional font. + // + // This matches historical Windows behavior and other browsers. + auto newSize = + aDefaultVariableFont.size.ToCSSPixels() - CSSPixel::FromPoints(2.0f); + aSystemFont->size = Length::FromPixels(std::max(float(newSize), 0.0f)); + } +} + +/* static */ +bool nsLayoutUtils::ShouldHandleMetaViewport(const Document* aDocument) { + auto metaViewportOverride = nsIDocShell::META_VIEWPORT_OVERRIDE_NONE; + if (aDocument) { + if (nsIDocShell* docShell = aDocument->GetDocShell()) { + metaViewportOverride = docShell->GetMetaViewportOverride(); + } + } + switch (metaViewportOverride) { + case nsIDocShell::META_VIEWPORT_OVERRIDE_ENABLED: + return true; + case nsIDocShell::META_VIEWPORT_OVERRIDE_DISABLED: + return false; + default: + MOZ_ASSERT(metaViewportOverride == + nsIDocShell::META_VIEWPORT_OVERRIDE_NONE); + // The META_VIEWPORT_OVERRIDE_NONE case means that there is no override + // and we rely solely on the StaticPrefs. + return StaticPrefs::dom_meta_viewport_enabled(); + } +} + +/* static */ +ComputedStyle* nsLayoutUtils::StyleForScrollbar(nsIFrame* aScrollbarPart) { + // Get the closest content node which is not an anonymous scrollbar + // part. It should be the originating element of the scrollbar part. + nsIContent* content = aScrollbarPart->GetContent(); + // Note that the content may be a normal element with scrollbar part + // value specified for its -moz-appearance, so don't rely on it being + // a native anonymous. Also note that we have to check the node name + // because anonymous element like generated content may originate a + // scrollbar. + MOZ_ASSERT(content, "No content for the scrollbar part?"); + while (content && content->IsInNativeAnonymousSubtree() && + content->IsAnyOfXULElements( + nsGkAtoms::scrollbar, nsGkAtoms::scrollbarbutton, + nsGkAtoms::scrollcorner, nsGkAtoms::slider, nsGkAtoms::thumb)) { + content = content->GetParent(); + } + MOZ_ASSERT(content, "Native anonymous element with no originating node?"); + // Use the style from the primary frame of the content. + // Note: it is important to use the primary frame rather than an + // ancestor frame of the scrollbar part for the correct handling of + // viewport scrollbar. The content of the scroll frame of the viewport + // is the root element, but its style inherits from the viewport. + // Since we need to use the style of root element for the viewport + // scrollbar, we have to get the style from the primary frame. + if (nsIFrame* primaryFrame = content->GetPrimaryFrame()) { + return primaryFrame->Style(); + } + // If the element doesn't have primary frame, get the computed style + // from the element directly. This can happen on viewport, because + // the scrollbar of viewport may be shown when the root element has + // > display: none; overflow: scroll; + MOZ_ASSERT( + content == aScrollbarPart->PresContext()->Document()->GetRootElement(), + "Root element is the only case for this fallback " + "path to be triggered"); + RefPtr<ComputedStyle> style = + ServoStyleSet::ResolveServoStyle(*content->AsElement()); + // Dropping the strong reference is fine because the style should be + // held strongly by the element. + return style.get(); +} + +enum class FramePosition : uint8_t { + Unknown, + InView, + OutOfView, +}; + +// NOTE: Returns a pair of Nothing() and `FramePosition::Unknown` if |aFrame| +// is not in out-of-process or if we haven't received enough information from +// APZ. +static std::pair<Maybe<ScreenRect>, FramePosition> GetFrameVisibleRectOnScreen( + const nsIFrame* aFrame) { + // We actually want the in-process top prescontext here. + nsPresContext* topContextInProcess = + aFrame->PresContext()->GetInProcessRootContentDocumentPresContext(); + if (!topContextInProcess) { + // We are in chrome process. + return std::make_pair(Nothing(), FramePosition::Unknown); + } + + if (topContextInProcess->Document()->IsTopLevelContentDocument()) { + // We are in the top of content document. + return std::make_pair(Nothing(), FramePosition::Unknown); + } + + nsIDocShell* docShell = topContextInProcess->GetDocShell(); + BrowserChild* browserChild = BrowserChild::GetFrom(docShell); + if (!browserChild) { + // We are not in out-of-process iframe. + return std::make_pair(Nothing(), FramePosition::Unknown); + } + + if (!browserChild->GetEffectsInfo().IsVisible()) { + // There is no visible rect on this iframe at all. + return std::make_pair(Some(ScreenRect()), FramePosition::Unknown); + } + + Maybe<ScreenRect> visibleRect = + browserChild->GetTopLevelViewportVisibleRectInBrowserCoords(); + if (!visibleRect) { + // We are unsure if we haven't received the transformed rectangle of the + // iframe's visible area. + return std::make_pair(Nothing(), FramePosition::Unknown); + } + + nsIFrame* rootFrame = topContextInProcess->PresShell()->GetRootFrame(); + nsRect transformedToIFrame = nsLayoutUtils::TransformFrameRectToAncestor( + aFrame, aFrame->InkOverflowRectRelativeToSelf(), rootFrame); + + LayoutDeviceRect rectInLayoutDevicePixel = LayoutDeviceRect::FromAppUnits( + transformedToIFrame, topContextInProcess->AppUnitsPerDevPixel()); + + ScreenRect transformedToRoot = ViewAs<ScreenPixel>( + browserChild->GetChildToParentConversionMatrix().TransformBounds( + rectInLayoutDevicePixel), + PixelCastJustification::ContentProcessIsLayerInUiProcess); + + FramePosition position = FramePosition::Unknown; + // we need to check whether the transformed rect is outside the iframe + // visible rect or not because in some cases the rect size is (0x0), thus + // the intersection between the transformed rect and the iframe visible rect + // would also be (0x0), then we can't tell whether the given nsIFrame is + // inside the iframe visible rect or not by calling BaseRect::IsEmpty for the + // intersection. + if (transformedToRoot.x > visibleRect->XMost() || + transformedToRoot.y > visibleRect->YMost() || + visibleRect->x > transformedToRoot.XMost() || + visibleRect->y > transformedToRoot.YMost()) { + position = FramePosition::OutOfView; + } else { + position = FramePosition::InView; + } + + return std::make_pair(Some(visibleRect->Intersect(transformedToRoot)), + position); +} + +// static +bool nsLayoutUtils::FrameIsScrolledOutOfViewInCrossProcess( + const nsIFrame* aFrame) { + auto [visibleRect, framePosition] = GetFrameVisibleRectOnScreen(aFrame); + if (visibleRect.isNothing()) { + return false; + } + + return visibleRect->IsEmpty() && framePosition != FramePosition::InView; +} + +// static +bool nsLayoutUtils::FrameIsMostlyScrolledOutOfViewInCrossProcess( + const nsIFrame* aFrame, nscoord aMargin) { + auto [visibleRect, framePosition] = GetFrameVisibleRectOnScreen(aFrame); + (void)framePosition; + if (visibleRect.isNothing()) { + return false; + } + + nsPresContext* topContextInProcess = + aFrame->PresContext()->GetInProcessRootContentDocumentPresContext(); + MOZ_ASSERT(topContextInProcess); + + nsIDocShell* docShell = topContextInProcess->GetDocShell(); + BrowserChild* browserChild = BrowserChild::GetFrom(docShell); + MOZ_ASSERT(browserChild); + + auto scale = + browserChild->GetChildToParentConversionMatrix().As2D().ScaleFactors(); + ScreenSize margin(scale.xScale * CSSPixel::FromAppUnits(aMargin), + scale.yScale * CSSPixel::FromAppUnits(aMargin)); + + return visibleRect->width < margin.width || + visibleRect->height < margin.height; +} + +// static +nsSize nsLayoutUtils::ExpandHeightForViewportUnits(nsPresContext* aPresContext, + const nsSize& aSize) { + nsSize sizeForViewportUnits = aPresContext->GetSizeForViewportUnits(); + + // |aSize| might be the size expanded to the minimum-scale size whereas the + // size for viewport units is not scaled so that we need to expand the |aSize| + // height by multiplying by the ratio of the viewport units height to the + // visible area height. + float vhExpansionRatio = (float)sizeForViewportUnits.height / + aPresContext->GetVisibleArea().height; + + MOZ_ASSERT(aSize.height <= NSCoordSaturatingNonnegativeMultiply( + aSize.height, vhExpansionRatio)); + return nsSize(aSize.width, NSCoordSaturatingNonnegativeMultiply( + aSize.height, vhExpansionRatio)); +} + +template <typename SizeType> +/* static */ SizeType ExpandHeightForDynamicToolbarImpl( + const nsPresContext* aPresContext, const SizeType& aSize) { + MOZ_ASSERT(aPresContext); + + LayoutDeviceIntSize displaySize; + if (RefPtr<MobileViewportManager> MVM = + aPresContext->PresShell()->GetMobileViewportManager()) { + displaySize = MVM->DisplaySize(); + } else if (!nsLayoutUtils::GetContentViewerSize(aPresContext, displaySize)) { + return aSize; + } + + float toolbarHeightRatio = + mozilla::ScreenCoord(aPresContext->GetDynamicToolbarMaxHeight()) / + mozilla::ViewAs<mozilla::ScreenPixel>( + displaySize, + mozilla::PixelCastJustification::LayoutDeviceIsScreenForBounds) + .height; + + SizeType expandedSize = aSize; + static_assert(std::is_same_v<nsSize, SizeType> || + std::is_same_v<CSSSize, SizeType>); + if constexpr (std::is_same_v<nsSize, SizeType>) { + expandedSize.height = + NSCoordSaturatingAdd(aSize.height, aSize.height * toolbarHeightRatio); + } else if (std::is_same_v<CSSSize, SizeType>) { + expandedSize.height = aSize.height + aSize.height * toolbarHeightRatio; + } + return expandedSize; +} + +CSSSize nsLayoutUtils::ExpandHeightForDynamicToolbar( + const nsPresContext* aPresContext, const CSSSize& aSize) { + return ExpandHeightForDynamicToolbarImpl(aPresContext, aSize); +} +nsSize nsLayoutUtils::ExpandHeightForDynamicToolbar( + const nsPresContext* aPresContext, const nsSize& aSize) { + return ExpandHeightForDynamicToolbarImpl(aPresContext, aSize); +} |