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-rw-r--r--layout/generic/nsCanvasFrame.cpp861
1 files changed, 861 insertions, 0 deletions
diff --git a/layout/generic/nsCanvasFrame.cpp b/layout/generic/nsCanvasFrame.cpp
new file mode 100644
index 0000000000..5efda8d41d
--- /dev/null
+++ b/layout/generic/nsCanvasFrame.cpp
@@ -0,0 +1,861 @@
+/* -*- 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/. */
+
+/* rendering object that goes directly inside the document's scrollbars */
+
+#include "nsCanvasFrame.h"
+
+#include "gfxContext.h"
+#include "gfxUtils.h"
+#include "nsContainerFrame.h"
+#include "nsContentCreatorFunctions.h"
+#include "nsCSSRendering.h"
+#include "nsPresContext.h"
+#include "nsGkAtoms.h"
+#include "nsIFrameInlines.h"
+#include "nsDisplayList.h"
+#include "nsCSSFrameConstructor.h"
+#include "nsFrameManager.h"
+#include "gfxPlatform.h"
+#include "nsPrintfCString.h"
+#include "mozilla/AccessibleCaretEventHub.h"
+#include "mozilla/BasePrincipal.h"
+#include "mozilla/ComputedStyle.h"
+#include "mozilla/StaticPrefs_browser.h"
+#include "mozilla/StaticPrefs_layout.h"
+#include "mozilla/dom/AnonymousContent.h"
+#include "mozilla/layers/StackingContextHelper.h"
+#include "mozilla/layers/RenderRootStateManager.h"
+#include "mozilla/PresShell.h"
+// for focus
+#include "nsIScrollableFrame.h"
+#ifdef DEBUG_CANVAS_FOCUS
+# include "nsIDocShell.h"
+#endif
+
+// #define DEBUG_CANVAS_FOCUS
+
+using namespace mozilla;
+using namespace mozilla::dom;
+using namespace mozilla::layout;
+using namespace mozilla::gfx;
+using namespace mozilla::layers;
+
+nsCanvasFrame* NS_NewCanvasFrame(PresShell* aPresShell, ComputedStyle* aStyle) {
+ return new (aPresShell) nsCanvasFrame(aStyle, aPresShell->GetPresContext());
+}
+
+nsIPopupContainer* nsIPopupContainer::GetPopupContainer(PresShell* aPresShell) {
+ return aPresShell ? aPresShell->GetCanvasFrame() : nullptr;
+}
+
+NS_IMPL_FRAMEARENA_HELPERS(nsCanvasFrame)
+
+NS_QUERYFRAME_HEAD(nsCanvasFrame)
+ NS_QUERYFRAME_ENTRY(nsCanvasFrame)
+ NS_QUERYFRAME_ENTRY(nsIAnonymousContentCreator)
+ NS_QUERYFRAME_ENTRY(nsIPopupContainer)
+NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)
+
+void nsCanvasFrame::ShowCustomContentContainer() {
+ if (mCustomContentContainer) {
+ mCustomContentContainer->UnsetAttr(kNameSpaceID_None, nsGkAtoms::hidden,
+ true);
+ }
+}
+
+void nsCanvasFrame::HideCustomContentContainer() {
+ if (mCustomContentContainer) {
+ mCustomContentContainer->SetAttr(kNameSpaceID_None, nsGkAtoms::hidden,
+ u"true"_ns, true);
+ }
+}
+
+nsresult nsCanvasFrame::CreateAnonymousContent(
+ nsTArray<ContentInfo>& aElements) {
+ MOZ_ASSERT(!mCustomContentContainer);
+
+ if (!mContent) {
+ return NS_OK;
+ }
+
+ nsCOMPtr<Document> doc = mContent->OwnerDoc();
+
+ RefPtr<AccessibleCaretEventHub> eventHub =
+ PresShell()->GetAccessibleCaretEventHub();
+
+ // This will go through InsertAnonymousContent and such, and we don't really
+ // want it to end up inserting into our content container.
+ //
+ // FIXME(emilio): The fact that this enters into InsertAnonymousContent is a
+ // bit nasty, can we avoid it, maybe doing this off a scriptrunner?
+ if (eventHub) {
+ eventHub->Init();
+ }
+
+ // Create the custom content container.
+ mCustomContentContainer = doc->CreateHTMLElement(nsGkAtoms::div);
+#ifdef DEBUG
+ // We restyle our mCustomContentContainer, even though it's root anonymous
+ // content. Normally that's not OK because the frame constructor doesn't know
+ // how to order the frame tree in such cases, but we make this work for this
+ // particular case, so it's OK.
+ mCustomContentContainer->SetProperty(nsGkAtoms::restylableAnonymousNode,
+ reinterpret_cast<void*>(true));
+#endif // DEBUG
+
+ mCustomContentContainer->SetProperty(
+ nsGkAtoms::docLevelNativeAnonymousContent, reinterpret_cast<void*>(true));
+
+ // This will usually be done by the caller, but in this case we do it here,
+ // since we reuse the document's AnoymousContent list, and those survive
+ // across reframes and thus may already be flagged as being in an anonymous
+ // subtree. We don't really want to have this semi-broken state where
+ // anonymous nodes have a non-anonymous.
+ mCustomContentContainer->SetIsNativeAnonymousRoot();
+
+ aElements.AppendElement(mCustomContentContainer);
+
+ // Do not create an accessible object for the container.
+ mCustomContentContainer->SetAttr(kNameSpaceID_None, nsGkAtoms::role,
+ u"presentation"_ns, false);
+
+ mCustomContentContainer->SetAttr(kNameSpaceID_None, nsGkAtoms::_class,
+ u"moz-custom-content-container"_ns, false);
+
+ // Only create a frame for mCustomContentContainer if it has some children.
+ if (doc->GetAnonymousContents().IsEmpty()) {
+ HideCustomContentContainer();
+ }
+
+ for (RefPtr<AnonymousContent>& anonContent : doc->GetAnonymousContents()) {
+ if (nsCOMPtr<nsINode> parent = anonContent->ContentNode().GetParentNode()) {
+ // Parent had better be an old custom content container already removed
+ // from a reframe. Forget about it since we're about to get inserted in a
+ // new one.
+ //
+ // TODO(emilio): Maybe we should extend PostDestroyData and do this stuff
+ // there instead, or something...
+ MOZ_ASSERT(parent != mCustomContentContainer);
+ MOZ_ASSERT(parent->IsElement());
+ MOZ_ASSERT(parent->AsElement()->IsRootOfNativeAnonymousSubtree());
+ MOZ_ASSERT(!parent->IsInComposedDoc());
+ MOZ_ASSERT(!parent->GetParentNode());
+
+ parent->RemoveChildNode(&anonContent->ContentNode(), false);
+ }
+
+ mCustomContentContainer->AppendChildTo(&anonContent->ContentNode(), false,
+ IgnoreErrors());
+ }
+
+ // Create a popupgroup element for system privileged non-XUL documents to
+ // support context menus and tooltips.
+ if (XRE_IsParentProcess() && doc->NodePrincipal()->IsSystemPrincipal()) {
+ nsNodeInfoManager* nodeInfoManager = doc->NodeInfoManager();
+ RefPtr<NodeInfo> nodeInfo = nodeInfoManager->GetNodeInfo(
+ nsGkAtoms::tooltip, nullptr, kNameSpaceID_XUL, nsINode::ELEMENT_NODE);
+
+ nsresult rv = NS_NewXULElement(getter_AddRefs(mTooltipContent),
+ nodeInfo.forget(), dom::NOT_FROM_PARSER);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ mTooltipContent->SetAttr(kNameSpaceID_None, nsGkAtoms::_default, u"true"_ns,
+ false);
+ // Set the page attribute so XULTooltipElement::PostHandleEvent will find
+ // the text for the tooltip from the currently hovered element.
+ mTooltipContent->SetAttr(kNameSpaceID_None, nsGkAtoms::page, u"true"_ns,
+ false);
+
+ mTooltipContent->SetProperty(nsGkAtoms::docLevelNativeAnonymousContent,
+ reinterpret_cast<void*>(true));
+
+ aElements.AppendElement(mTooltipContent);
+ }
+
+#ifdef DEBUG
+ for (auto& element : aElements) {
+ MOZ_ASSERT(element.mContent->GetProperty(
+ nsGkAtoms::docLevelNativeAnonymousContent),
+ "NAC from the canvas frame needs to be document-level, otherwise"
+ " it (1) inherits from the document which is unexpected, and (2)"
+ " StyleChildrenIterator won't be able to find it properly");
+ }
+#endif
+ return NS_OK;
+}
+
+void nsCanvasFrame::AppendAnonymousContentTo(nsTArray<nsIContent*>& aElements,
+ uint32_t aFilter) {
+ if (mCustomContentContainer) {
+ aElements.AppendElement(mCustomContentContainer);
+ }
+ if (mTooltipContent) {
+ aElements.AppendElement(mTooltipContent);
+ }
+}
+
+void nsCanvasFrame::Destroy(DestroyContext& aContext) {
+ nsIScrollableFrame* sf =
+ PresContext()->GetPresShell()->GetRootScrollFrameAsScrollable();
+ if (sf) {
+ sf->RemoveScrollPositionListener(this);
+ }
+
+ aContext.AddAnonymousContent(mCustomContentContainer.forget());
+ if (mTooltipContent) {
+ aContext.AddAnonymousContent(mTooltipContent.forget());
+ }
+ nsContainerFrame::Destroy(aContext);
+}
+
+void nsCanvasFrame::ScrollPositionWillChange(nscoord aX, nscoord aY) {
+ if (mDoPaintFocus) {
+ mDoPaintFocus = false;
+ PresShell()->GetRootFrame()->InvalidateFrameSubtree();
+ }
+}
+
+NS_IMETHODIMP
+nsCanvasFrame::SetHasFocus(bool aHasFocus) {
+ if (mDoPaintFocus != aHasFocus) {
+ mDoPaintFocus = aHasFocus;
+ PresShell()->GetRootFrame()->InvalidateFrameSubtree();
+
+ if (!mAddedScrollPositionListener) {
+ nsIScrollableFrame* sf =
+ PresContext()->GetPresShell()->GetRootScrollFrameAsScrollable();
+ if (sf) {
+ sf->AddScrollPositionListener(this);
+ mAddedScrollPositionListener = true;
+ }
+ }
+ }
+ return NS_OK;
+}
+
+void nsCanvasFrame::SetInitialChildList(ChildListID aListID,
+ nsFrameList&& aChildList) {
+ NS_ASSERTION(aListID != FrameChildListID::Principal || aChildList.IsEmpty() ||
+ aChildList.OnlyChild(),
+ "Primary child list can have at most one frame in it");
+ nsContainerFrame::SetInitialChildList(aListID, std::move(aChildList));
+}
+
+void nsCanvasFrame::AppendFrames(ChildListID aListID,
+ nsFrameList&& aFrameList) {
+#ifdef DEBUG
+ MOZ_ASSERT(aListID == FrameChildListID::Principal, "unexpected child list");
+ if (!mFrames.IsEmpty()) {
+ for (nsIFrame* f : aFrameList) {
+ // We only allow native anonymous child frames to be in principal child
+ // list in canvas frame.
+ MOZ_ASSERT(f->GetContent()->IsInNativeAnonymousSubtree(),
+ "invalid child list");
+ }
+ }
+ nsIFrame::VerifyDirtyBitSet(aFrameList);
+#endif
+ nsContainerFrame::AppendFrames(aListID, std::move(aFrameList));
+}
+
+void nsCanvasFrame::InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame,
+ const nsLineList::iterator* aPrevFrameLine,
+ nsFrameList&& aFrameList) {
+ // Because we only support a single child frame inserting is the same
+ // as appending
+ MOZ_ASSERT(!aPrevFrame, "unexpected previous sibling frame");
+ AppendFrames(aListID, std::move(aFrameList));
+}
+
+#ifdef DEBUG
+void nsCanvasFrame::RemoveFrame(DestroyContext& aContext, ChildListID aListID,
+ nsIFrame* aOldFrame) {
+ MOZ_ASSERT(aListID == FrameChildListID::Principal, "unexpected child list");
+ nsContainerFrame::RemoveFrame(aContext, aListID, aOldFrame);
+}
+#endif
+
+nsRect nsCanvasFrame::CanvasArea() const {
+ // Not clear which overflow rect we want here, but it probably doesn't
+ // matter.
+ nsRect result(InkOverflowRect());
+
+ nsIScrollableFrame* scrollableFrame = do_QueryFrame(GetParent());
+ if (scrollableFrame) {
+ nsRect portRect = scrollableFrame->GetScrollPortRect();
+ result.UnionRect(result, nsRect(nsPoint(0, 0), portRect.Size()));
+ }
+ return result;
+}
+
+Element* nsCanvasFrame::GetDefaultTooltip() { return mTooltipContent; }
+
+void nsDisplayCanvasBackgroundColor::Paint(nsDisplayListBuilder* aBuilder,
+ gfxContext* aCtx) {
+ nsCanvasFrame* frame = static_cast<nsCanvasFrame*>(mFrame);
+ nsPoint offset = ToReferenceFrame();
+ nsRect bgClipRect = frame->CanvasArea() + offset;
+ if (NS_GET_A(mColor) > 0) {
+ DrawTarget* drawTarget = aCtx->GetDrawTarget();
+ int32_t appUnitsPerDevPixel = mFrame->PresContext()->AppUnitsPerDevPixel();
+ Rect devPxRect =
+ NSRectToSnappedRect(bgClipRect, appUnitsPerDevPixel, *drawTarget);
+ drawTarget->FillRect(devPxRect, ColorPattern(ToDeviceColor(mColor)));
+ }
+}
+
+bool nsDisplayCanvasBackgroundColor::CreateWebRenderCommands(
+ mozilla::wr::DisplayListBuilder& aBuilder,
+ mozilla::wr::IpcResourceUpdateQueue& aResources,
+ const StackingContextHelper& aSc, RenderRootStateManager* aManager,
+ nsDisplayListBuilder* aDisplayListBuilder) {
+ nsCanvasFrame* frame = static_cast<nsCanvasFrame*>(mFrame);
+ nsPoint offset = ToReferenceFrame();
+ nsRect bgClipRect = frame->CanvasArea() + offset;
+ int32_t appUnitsPerDevPixel = mFrame->PresContext()->AppUnitsPerDevPixel();
+
+ LayoutDeviceRect rect =
+ LayoutDeviceRect::FromAppUnits(bgClipRect, appUnitsPerDevPixel);
+
+ wr::LayoutRect r = wr::ToLayoutRect(rect);
+ aBuilder.PushRect(r, r, !BackfaceIsHidden(), false, false,
+ wr::ToColorF(ToDeviceColor(mColor)));
+ return true;
+}
+
+void nsDisplayCanvasBackgroundColor::WriteDebugInfo(
+ std::stringstream& aStream) {
+ aStream << " (rgba " << (int)NS_GET_R(mColor) << "," << (int)NS_GET_G(mColor)
+ << "," << (int)NS_GET_B(mColor) << "," << (int)NS_GET_A(mColor)
+ << ")";
+}
+
+void nsDisplayCanvasBackgroundImage::Paint(nsDisplayListBuilder* aBuilder,
+ gfxContext* aCtx) {
+ nsCanvasFrame* frame = static_cast<nsCanvasFrame*>(mFrame);
+ nsPoint offset = ToReferenceFrame();
+ nsRect bgClipRect = frame->CanvasArea() + offset;
+
+ PaintInternal(aBuilder, aCtx, GetPaintRect(aBuilder, aCtx), &bgClipRect);
+}
+
+bool nsDisplayCanvasBackgroundImage::IsSingleFixedPositionImage(
+ nsDisplayListBuilder* aBuilder, const nsRect& aClipRect,
+ gfxRect* aDestRect) {
+ if (!mBackgroundStyle) return false;
+
+ if (mBackgroundStyle->StyleBackground()->mImage.mLayers.Length() != 1)
+ return false;
+
+ nsPresContext* presContext = mFrame->PresContext();
+ uint32_t flags = aBuilder->GetBackgroundPaintFlags();
+ nsRect borderArea = nsRect(ToReferenceFrame(), mFrame->GetSize());
+ const nsStyleImageLayers::Layer& layer =
+ mBackgroundStyle->StyleBackground()->mImage.mLayers[mLayer];
+
+ if (layer.mAttachment != StyleImageLayerAttachment::Fixed) return false;
+
+ nsBackgroundLayerState state = nsCSSRendering::PrepareImageLayer(
+ presContext, mFrame, flags, borderArea, aClipRect, layer);
+
+ // We only care about images here, not gradients.
+ if (!mIsRasterImage) return false;
+
+ int32_t appUnitsPerDevPixel = presContext->AppUnitsPerDevPixel();
+ *aDestRect =
+ nsLayoutUtils::RectToGfxRect(state.mFillArea, appUnitsPerDevPixel);
+
+ return true;
+}
+
+void nsDisplayCanvasThemedBackground::Paint(nsDisplayListBuilder* aBuilder,
+ gfxContext* aCtx) {
+ nsCanvasFrame* frame = static_cast<nsCanvasFrame*>(mFrame);
+ nsPoint offset = ToReferenceFrame();
+ nsRect bgClipRect = frame->CanvasArea() + offset;
+
+ PaintInternal(aBuilder, aCtx, GetPaintRect(aBuilder, aCtx), &bgClipRect);
+}
+
+/**
+ * A display item to paint the focus ring for the document.
+ *
+ * The only reason this can't use nsDisplayGeneric is overriding GetBounds.
+ */
+class nsDisplayCanvasFocus : public nsPaintedDisplayItem {
+ public:
+ nsDisplayCanvasFocus(nsDisplayListBuilder* aBuilder, nsCanvasFrame* aFrame)
+ : nsPaintedDisplayItem(aBuilder, aFrame) {
+ MOZ_COUNT_CTOR(nsDisplayCanvasFocus);
+ }
+ MOZ_COUNTED_DTOR_OVERRIDE(nsDisplayCanvasFocus)
+
+ virtual nsRect GetBounds(nsDisplayListBuilder* aBuilder,
+ bool* aSnap) const override {
+ *aSnap = false;
+ // This is an overestimate, but that's not a problem.
+ nsCanvasFrame* frame = static_cast<nsCanvasFrame*>(mFrame);
+ return frame->CanvasArea() + ToReferenceFrame();
+ }
+
+ virtual void Paint(nsDisplayListBuilder* aBuilder,
+ gfxContext* aCtx) override {
+ nsCanvasFrame* frame = static_cast<nsCanvasFrame*>(mFrame);
+ frame->PaintFocus(aCtx->GetDrawTarget(), ToReferenceFrame());
+ }
+
+ NS_DISPLAY_DECL_NAME("CanvasFocus", TYPE_CANVAS_FOCUS)
+};
+
+void nsCanvasFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
+ const nsDisplayListSet& aLists) {
+ if (GetPrevInFlow()) {
+ DisplayOverflowContainers(aBuilder, aLists);
+ }
+
+ // Force a background to be shown. We may have a background propagated to us,
+ // in which case StyleBackground wouldn't have the right background
+ // and the code in nsIFrame::DisplayBorderBackgroundOutline might not give us
+ // a background.
+ // We don't have any border or outline, and our background draws over
+ // the overflow area, so just add nsDisplayCanvasBackground instead of
+ // calling DisplayBorderBackgroundOutline.
+ if (IsVisibleForPainting()) {
+ ComputedStyle* bg = nullptr;
+ nsIFrame* dependentFrame = nullptr;
+ bool isThemed = IsThemed();
+ if (!isThemed) {
+ dependentFrame = nsCSSRendering::FindBackgroundFrame(this);
+ if (dependentFrame) {
+ bg = dependentFrame->Style();
+ if (dependentFrame == this) {
+ dependentFrame = nullptr;
+ }
+ }
+ }
+
+ if (isThemed) {
+ aLists.BorderBackground()
+ ->AppendNewToTop<nsDisplayCanvasThemedBackground>(aBuilder, this);
+ return;
+ }
+
+ if (!bg) {
+ return;
+ }
+
+ const ActiveScrolledRoot* asr = aBuilder->CurrentActiveScrolledRoot();
+
+ bool needBlendContainer = false;
+ nsDisplayListBuilder::AutoContainerASRTracker contASRTracker(aBuilder);
+
+ const bool suppressBackgroundImage = [&] {
+ // Handle print settings.
+ if (!ComputeShouldPaintBackground().mImage) {
+ return true;
+ }
+ // In high-contrast-mode, we suppress background-image on the canvas frame
+ // (even when backplating), because users expect site backgrounds to
+ // conform to their HCM background color when a solid color is rendered,
+ // and some websites use solid-color images instead of an overwritable
+ // background color.
+ if (PresContext()->ForcingColors() &&
+ StaticPrefs::
+ browser_display_suppress_canvas_background_image_on_forced_colors()) {
+ return true;
+ }
+ return false;
+ }();
+
+ nsDisplayList layerItems(aBuilder);
+
+ // Create separate items for each background layer.
+ const nsStyleImageLayers& layers = bg->StyleBackground()->mImage;
+ NS_FOR_VISIBLE_IMAGE_LAYERS_BACK_TO_FRONT(i, layers) {
+ if (layers.mLayers[i].mImage.IsNone() || suppressBackgroundImage) {
+ continue;
+ }
+ if (layers.mLayers[i].mBlendMode != StyleBlend::Normal) {
+ needBlendContainer = true;
+ }
+
+ nsRect bgRect =
+ GetRectRelativeToSelf() + aBuilder->ToReferenceFrame(this);
+
+ const ActiveScrolledRoot* thisItemASR = asr;
+ nsDisplayList thisItemList(aBuilder);
+ nsDisplayBackgroundImage::InitData bgData =
+ nsDisplayBackgroundImage::GetInitData(aBuilder, this, i, bgRect, bg);
+
+ if (bgData.shouldFixToViewport) {
+ auto* displayData = aBuilder->GetCurrentFixedBackgroundDisplayData();
+ nsDisplayListBuilder::AutoBuildingDisplayList buildingDisplayList(
+ aBuilder, this, aBuilder->GetVisibleRect(),
+ aBuilder->GetDirtyRect());
+
+ DisplayListClipState::AutoSaveRestore clipState(aBuilder);
+ nsDisplayListBuilder::AutoCurrentActiveScrolledRootSetter asrSetter(
+ aBuilder);
+ if (displayData) {
+ nsPoint offset =
+ GetOffsetTo(PresContext()->GetPresShell()->GetRootFrame());
+ aBuilder->SetVisibleRect(displayData->mVisibleRect + offset);
+ aBuilder->SetDirtyRect(displayData->mDirtyRect + offset);
+
+ clipState.SetClipChainForContainingBlockDescendants(
+ displayData->mContainingBlockClipChain);
+ asrSetter.SetCurrentActiveScrolledRoot(
+ displayData->mContainingBlockActiveScrolledRoot);
+ asrSetter.SetCurrentScrollParentId(displayData->mScrollParentId);
+ thisItemASR = displayData->mContainingBlockActiveScrolledRoot;
+ }
+ nsDisplayCanvasBackgroundImage* bgItem = nullptr;
+ {
+ DisplayListClipState::AutoSaveRestore bgImageClip(aBuilder);
+ bgImageClip.Clear();
+ bgItem = MakeDisplayItemWithIndex<nsDisplayCanvasBackgroundImage>(
+ aBuilder, this, /* aIndex = */ i, bgData);
+ if (bgItem) {
+ bgItem->SetDependentFrame(aBuilder, dependentFrame);
+ }
+ }
+ if (bgItem) {
+ thisItemList.AppendToTop(
+ nsDisplayFixedPosition::CreateForFixedBackground(
+ aBuilder, this, nullptr, bgItem, i, asr));
+ }
+
+ } else {
+ nsDisplayCanvasBackgroundImage* bgItem =
+ MakeDisplayItemWithIndex<nsDisplayCanvasBackgroundImage>(
+ aBuilder, this, /* aIndex = */ i, bgData);
+ if (bgItem) {
+ bgItem->SetDependentFrame(aBuilder, dependentFrame);
+ thisItemList.AppendToTop(bgItem);
+ }
+ }
+
+ if (layers.mLayers[i].mBlendMode != StyleBlend::Normal) {
+ DisplayListClipState::AutoSaveRestore blendClip(aBuilder);
+ thisItemList.AppendNewToTopWithIndex<nsDisplayBlendMode>(
+ aBuilder, this, i + 1, &thisItemList, layers.mLayers[i].mBlendMode,
+ thisItemASR, true);
+ }
+ layerItems.AppendToTop(&thisItemList);
+ }
+
+ bool hasFixedBottomLayer =
+ layers.mImageCount > 0 &&
+ layers.mLayers[0].mAttachment == StyleImageLayerAttachment::Fixed;
+
+ if (!hasFixedBottomLayer || needBlendContainer) {
+ // Put a scrolled background color item in place, at the bottom of the
+ // list. The color of this item will be filled in during
+ // PresShell::AddCanvasBackgroundColorItem.
+ // Do not add this item if there's a fixed background image at the bottom
+ // (unless we have to, for correct blending); with a fixed background,
+ // it's better to allow the fixed background image to combine itself with
+ // a non-scrolled background color directly underneath, rather than
+ // interleaving the two with a scrolled background color.
+ // PresShell::AddCanvasBackgroundColorItem makes sure there always is a
+ // non-scrolled background color item at the bottom.
+ aLists.BorderBackground()->AppendNewToTop<nsDisplayCanvasBackgroundColor>(
+ aBuilder, this);
+ }
+
+ aLists.BorderBackground()->AppendToTop(&layerItems);
+
+ if (needBlendContainer) {
+ const ActiveScrolledRoot* containerASR = contASRTracker.GetContainerASR();
+ DisplayListClipState::AutoSaveRestore blendContainerClip(aBuilder);
+ aLists.BorderBackground()->AppendToTop(
+ nsDisplayBlendContainer::CreateForBackgroundBlendMode(
+ aBuilder, this, nullptr, aLists.BorderBackground(),
+ containerASR));
+ }
+ }
+
+ for (nsIFrame* kid : PrincipalChildList()) {
+ // Put our child into its own pseudo-stack.
+ BuildDisplayListForChild(aBuilder, kid, aLists);
+ }
+
+#ifdef DEBUG_CANVAS_FOCUS
+ nsCOMPtr<nsIContent> focusContent;
+ aPresContext->EventStateManager()->GetFocusedContent(
+ getter_AddRefs(focusContent));
+
+ bool hasFocus = false;
+ nsCOMPtr<nsISupports> container;
+ aPresContext->GetContainer(getter_AddRefs(container));
+ nsCOMPtr<nsIDocShell> docShell(do_QueryInterface(container));
+ if (docShell) {
+ docShell->GetHasFocus(&hasFocus);
+ nsRect dirty = aBuilder->GetDirtyRect();
+ printf("%p - nsCanvasFrame::Paint R:%d,%d,%d,%d DR: %d,%d,%d,%d\n", this,
+ mRect.x, mRect.y, mRect.width, mRect.height, dirty.x, dirty.y,
+ dirty.width, dirty.height);
+ }
+ printf("%p - Focus: %s c: %p DoPaint:%s\n", docShell.get(),
+ hasFocus ? "Y" : "N", focusContent.get(), mDoPaintFocus ? "Y" : "N");
+#endif
+
+ if (!mDoPaintFocus) return;
+ // Only paint the focus if we're visible
+ if (!StyleVisibility()->IsVisible()) return;
+
+ aLists.Outlines()->AppendNewToTop<nsDisplayCanvasFocus>(aBuilder, this);
+}
+
+void nsCanvasFrame::PaintFocus(DrawTarget* aDrawTarget, nsPoint aPt) {
+ nsRect focusRect(aPt, GetSize());
+
+ nsIScrollableFrame* scrollableFrame = do_QueryFrame(GetParent());
+ if (scrollableFrame) {
+ nsRect portRect = scrollableFrame->GetScrollPortRect();
+ focusRect.width = portRect.width;
+ focusRect.height = portRect.height;
+ focusRect.MoveBy(scrollableFrame->GetScrollPosition());
+ }
+
+ // XXX use the root frame foreground color, but should we find BODY frame
+ // for HTML documents?
+ nsIFrame* root = mFrames.FirstChild();
+ const auto* text = root ? root->StyleText() : StyleText();
+ nsCSSRendering::PaintFocus(PresContext(), aDrawTarget, focusRect,
+ text->mColor.ToColor());
+}
+
+/* virtual */
+nscoord nsCanvasFrame::GetMinISize(gfxContext* aRenderingContext) {
+ nscoord result;
+ DISPLAY_MIN_INLINE_SIZE(this, result);
+ if (mFrames.IsEmpty())
+ result = 0;
+ else
+ result = mFrames.FirstChild()->GetMinISize(aRenderingContext);
+ return result;
+}
+
+/* virtual */
+nscoord nsCanvasFrame::GetPrefISize(gfxContext* aRenderingContext) {
+ nscoord result;
+ DISPLAY_PREF_INLINE_SIZE(this, result);
+ if (mFrames.IsEmpty())
+ result = 0;
+ else
+ result = mFrames.FirstChild()->GetPrefISize(aRenderingContext);
+ return result;
+}
+
+void nsCanvasFrame::Reflow(nsPresContext* aPresContext,
+ ReflowOutput& aDesiredSize,
+ const ReflowInput& aReflowInput,
+ nsReflowStatus& aStatus) {
+ MarkInReflow();
+ DO_GLOBAL_REFLOW_COUNT("nsCanvasFrame");
+ DISPLAY_REFLOW(aPresContext, this, aReflowInput, aDesiredSize, aStatus);
+ MOZ_ASSERT(aStatus.IsEmpty(), "Caller should pass a fresh reflow status!");
+ NS_FRAME_TRACE_REFLOW_IN("nsCanvasFrame::Reflow");
+
+ nsCanvasFrame* prevCanvasFrame = static_cast<nsCanvasFrame*>(GetPrevInFlow());
+ if (prevCanvasFrame) {
+ AutoFrameListPtr overflow(aPresContext,
+ prevCanvasFrame->StealOverflowFrames());
+ if (overflow) {
+ NS_ASSERTION(overflow->OnlyChild(),
+ "must have doc root as canvas frame's only child");
+ nsContainerFrame::ReparentFrameViewList(*overflow, prevCanvasFrame, this);
+ // Prepend overflow to the our child list. There may already be
+ // children placeholders for fixed-pos elements, which don't get
+ // reflowed but must not be lost until the canvas frame is destroyed.
+ mFrames.InsertFrames(this, nullptr, std::move(*overflow));
+ }
+ }
+
+ // Set our size up front, since some parts of reflow depend on it
+ // being already set. Note that the computed height may be
+ // unconstrained; that's ok. Consumers should watch out for that.
+ SetSize(nsSize(aReflowInput.ComputedWidth(), aReflowInput.ComputedHeight()));
+
+ // Reflow our children. Typically, we only have one child - the root
+ // element's frame or a placeholder for that frame, if the root element
+ // is abs-pos or fixed-pos. Note that this child might be missing though
+ // if that frame was Complete in one of our earlier continuations. This
+ // happens when we create additional pages purely to make room for painting
+ // overflow (painted by BuildPreviousPageOverflow in nsPageFrame.cpp).
+ // We may have additional children which are placeholders for continuations
+ // of fixed-pos content, see nsCSSFrameConstructor::ReplicateFixedFrames.
+ const WritingMode wm = aReflowInput.GetWritingMode();
+ aDesiredSize.SetSize(wm, aReflowInput.ComputedSize());
+ if (aReflowInput.ComputedBSize() == NS_UNCONSTRAINEDSIZE) {
+ // Set the block-size to zero for now in case we don't have any non-
+ // placeholder children that would update the size in the loop below.
+ aDesiredSize.BSize(wm) = nscoord(0);
+ }
+ aDesiredSize.SetOverflowAreasToDesiredBounds();
+ nsIFrame* nextKid = nullptr;
+ for (auto* kidFrame = mFrames.FirstChild(); kidFrame; kidFrame = nextKid) {
+ nextKid = kidFrame->GetNextSibling();
+ ReflowOutput kidDesiredSize(aReflowInput);
+ bool kidDirty = kidFrame->HasAnyStateBits(NS_FRAME_IS_DIRTY);
+ WritingMode kidWM = kidFrame->GetWritingMode();
+ auto availableSize = aReflowInput.AvailableSize(kidWM);
+ nscoord bOffset = 0;
+ nscoord canvasBSizeSum = 0;
+ if (prevCanvasFrame && availableSize.BSize(kidWM) != NS_UNCONSTRAINEDSIZE &&
+ !kidFrame->IsPlaceholderFrame() &&
+ StaticPrefs::layout_display_list_improve_fragmentation()) {
+ for (auto* pif = prevCanvasFrame; pif;
+ pif = static_cast<nsCanvasFrame*>(pif->GetPrevInFlow())) {
+ canvasBSizeSum += pif->BSize(kidWM);
+ auto* pifChild = pif->PrincipalChildList().FirstChild();
+ if (pifChild) {
+ nscoord layoutOverflow = pifChild->BSize(kidWM) - canvasBSizeSum;
+ // A negative value means that the :root frame does not fill
+ // the canvas. In this case we can't determine the offset exactly
+ // so we use the end edge of the scrollable overflow as the offset
+ // instead. This will likely push down the content below where it
+ // should be placed, creating a gap. That's preferred over making
+ // content overlap which would otherwise occur.
+ // See layout/reftests/pagination/inline-block-slice-7.html for an
+ // example of this.
+ if (layoutOverflow < 0) {
+ LogicalRect so(kidWM, pifChild->ScrollableOverflowRect(),
+ pifChild->GetSize());
+ layoutOverflow = so.BEnd(kidWM) - canvasBSizeSum;
+ }
+ bOffset = std::max(bOffset, layoutOverflow);
+ }
+ }
+ availableSize.BSize(kidWM) -= bOffset;
+ }
+
+ if (MOZ_LIKELY(availableSize.BSize(kidWM) > 0)) {
+ ReflowInput kidReflowInput(aPresContext, aReflowInput, kidFrame,
+ availableSize);
+
+ if (aReflowInput.IsBResizeForWM(kidReflowInput.GetWritingMode()) &&
+ kidFrame->HasAnyStateBits(NS_FRAME_CONTAINS_RELATIVE_BSIZE)) {
+ // Tell our kid it's being block-dir resized too. Bit of a
+ // hack for framesets.
+ kidReflowInput.SetBResize(true);
+ }
+
+ nsSize containerSize = aReflowInput.ComputedPhysicalSize();
+ LogicalMargin margin = kidReflowInput.ComputedLogicalMargin(kidWM);
+ LogicalPoint kidPt(kidWM, margin.IStart(kidWM), margin.BStart(kidWM));
+ (kidWM.IsOrthogonalTo(wm) ? kidPt.I(kidWM) : kidPt.B(kidWM)) += bOffset;
+
+ nsReflowStatus kidStatus;
+ ReflowChild(kidFrame, aPresContext, kidDesiredSize, kidReflowInput, kidWM,
+ kidPt, containerSize, ReflowChildFlags::Default, kidStatus);
+
+ FinishReflowChild(kidFrame, aPresContext, kidDesiredSize, &kidReflowInput,
+ kidWM, kidPt, containerSize,
+ ReflowChildFlags::ApplyRelativePositioning);
+
+ if (!kidStatus.IsFullyComplete()) {
+ nsIFrame* nextFrame = kidFrame->GetNextInFlow();
+ NS_ASSERTION(nextFrame || kidStatus.NextInFlowNeedsReflow(),
+ "If it's incomplete and has no nif yet, it must flag a "
+ "nif reflow.");
+ if (!nextFrame) {
+ nextFrame = aPresContext->PresShell()
+ ->FrameConstructor()
+ ->CreateContinuingFrame(kidFrame, this);
+ SetOverflowFrames(nsFrameList(nextFrame, nextFrame));
+ // Root overflow containers will be normal children of
+ // the canvas frame, but that's ok because there
+ // aren't any other frames we need to isolate them from
+ // during reflow.
+ }
+ if (kidStatus.IsOverflowIncomplete()) {
+ nextFrame->AddStateBits(NS_FRAME_IS_OVERFLOW_CONTAINER);
+ }
+ }
+ aStatus.MergeCompletionStatusFrom(kidStatus);
+
+ // If the child frame was just inserted, then we're responsible for making
+ // sure it repaints
+ if (kidDirty) {
+ // But we have a new child, which will affect our background, so
+ // invalidate our whole rect.
+ // Note: Even though we request to be sized to our child's size, our
+ // scroll frame ensures that we are always the size of the viewport.
+ // Also note: GetPosition() on a CanvasFrame is always going to return
+ // (0, 0). We only want to invalidate GetRect() since Get*OverflowRect()
+ // could also include overflow to our top and left (out of the viewport)
+ // which doesn't need to be painted.
+ nsIFrame* viewport = PresContext()->GetPresShell()->GetRootFrame();
+ viewport->InvalidateFrame();
+ }
+
+ // Return our desired size. Normally it's what we're told, but sometimes
+ // we can be given an unconstrained block-size (when a window is
+ // sizing-to-content), and we should compute our desired block-size. This
+ // is done by PresShell::ResizeReflow, when given the BSizeLimit flag.
+ //
+ // We do this here rather than at the viewport frame, because the canvas
+ // is what draws the background, so it can extend a little bit more than
+ // the real content without visual glitches, realistically.
+ if (aReflowInput.ComputedBSize() == NS_UNCONSTRAINEDSIZE &&
+ !kidFrame->IsPlaceholderFrame()) {
+ LogicalSize finalSize = aReflowInput.ComputedSize();
+ finalSize.BSize(wm) = nsPresContext::RoundUpAppUnitsToCSSPixel(
+ kidFrame->GetLogicalSize(wm).BSize(wm) +
+ kidReflowInput.ComputedLogicalMargin(wm).BStartEnd(wm));
+ aDesiredSize.SetSize(wm, finalSize);
+ aDesiredSize.SetOverflowAreasToDesiredBounds();
+ }
+ aDesiredSize.mOverflowAreas.UnionWith(kidDesiredSize.mOverflowAreas +
+ kidFrame->GetPosition());
+ } else if (kidFrame->IsPlaceholderFrame()) {
+ // Placeholders always fit even if there's no available block-size left.
+ } else {
+ // This only occurs in paginated mode. There is no available space on
+ // this page due to reserving space for overflow from a previous page,
+ // so we push our child to the next page. Note that we can have some
+ // placeholders for fixed pos. frames in mFrames too, so we need to be
+ // careful to only push `kidFrame`.
+ mFrames.RemoveFrame(kidFrame);
+ SetOverflowFrames(nsFrameList(kidFrame, kidFrame));
+ aStatus.SetIncomplete();
+ }
+ }
+
+ if (prevCanvasFrame) {
+ ReflowOverflowContainerChildren(aPresContext, aReflowInput,
+ aDesiredSize.mOverflowAreas,
+ ReflowChildFlags::Default, aStatus);
+ }
+
+ FinishReflowWithAbsoluteFrames(aPresContext, aDesiredSize, aReflowInput,
+ aStatus);
+
+ NS_FRAME_TRACE_REFLOW_OUT("nsCanvasFrame::Reflow", aStatus);
+}
+
+nsresult nsCanvasFrame::GetContentForEvent(const WidgetEvent* aEvent,
+ nsIContent** aContent) {
+ NS_ENSURE_ARG_POINTER(aContent);
+ nsresult rv = nsIFrame::GetContentForEvent(aEvent, aContent);
+ if (NS_FAILED(rv) || !*aContent) {
+ nsIFrame* kid = mFrames.FirstChild();
+ if (kid) {
+ rv = kid->GetContentForEvent(aEvent, aContent);
+ }
+ }
+
+ return rv;
+}
+
+#ifdef DEBUG_FRAME_DUMP
+nsresult nsCanvasFrame::GetFrameName(nsAString& aResult) const {
+ return MakeFrameName(u"Canvas"_ns, aResult);
+}
+#endif