diff options
Diffstat (limited to 'gfx/layers/apz/util/APZCCallbackHelper.cpp')
| -rw-r--r-- | gfx/layers/apz/util/APZCCallbackHelper.cpp | 940 |
1 files changed, 940 insertions, 0 deletions
diff --git a/gfx/layers/apz/util/APZCCallbackHelper.cpp b/gfx/layers/apz/util/APZCCallbackHelper.cpp new file mode 100644 index 0000000000..8b67baf316 --- /dev/null +++ b/gfx/layers/apz/util/APZCCallbackHelper.cpp @@ -0,0 +1,940 @@ +/* -*- 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 "APZCCallbackHelper.h" + +#include "gfxPlatform.h" // For gfxPlatform::UseTiling + +#include "mozilla/AsyncEventDispatcher.h" +#include "mozilla/EventForwards.h" +#include "mozilla/dom/CustomEvent.h" +#include "mozilla/dom/Element.h" +#include "mozilla/dom/MouseEventBinding.h" +#include "mozilla/dom/BrowserParent.h" +#include "mozilla/dom/ScriptSettings.h" +#include "mozilla/IntegerPrintfMacros.h" +#include "mozilla/layers/RepaintRequest.h" +#include "mozilla/layers/WebRenderLayerManager.h" +#include "mozilla/layers/WebRenderBridgeChild.h" +#include "mozilla/DisplayPortUtils.h" +#include "mozilla/PresShell.h" +#include "mozilla/ToString.h" +#include "mozilla/ViewportUtils.h" +#include "nsContainerFrame.h" +#include "nsContentUtils.h" +#include "nsIContent.h" +#include "nsIDOMWindowUtils.h" +#include "mozilla/dom/Document.h" +#include "nsIInterfaceRequestorUtils.h" +#include "nsIScrollableFrame.h" +#include "nsLayoutUtils.h" +#include "nsPrintfCString.h" +#include "nsPIDOMWindow.h" +#include "nsRefreshDriver.h" +#include "nsString.h" +#include "nsView.h" + +static mozilla::LazyLogModule sApzHlpLog("apz.helper"); +#define APZCCH_LOG(...) MOZ_LOG(sApzHlpLog, LogLevel::Debug, (__VA_ARGS__)) +static mozilla::LazyLogModule sDisplayportLog("apz.displayport"); + +namespace mozilla { +namespace layers { + +using dom::BrowserParent; + +uint64_t APZCCallbackHelper::sLastTargetAPZCNotificationInputBlock = + uint64_t(-1); + +static ScreenMargin RecenterDisplayPort(const ScreenMargin& aDisplayPort) { + ScreenMargin margins = aDisplayPort; + margins.right = margins.left = margins.LeftRight() / 2; + margins.top = margins.bottom = margins.TopBottom() / 2; + return margins; +} + +static PresShell* GetPresShell(const nsIContent* aContent) { + if (dom::Document* doc = aContent->GetComposedDoc()) { + return doc->GetPresShell(); + } + return nullptr; +} + +static CSSPoint ScrollFrameTo(nsIScrollableFrame* aFrame, + const RepaintRequest& aRequest, + bool& aSuccessOut) { + aSuccessOut = false; + CSSPoint targetScrollPosition = aRequest.GetLayoutScrollOffset(); + + if (!aFrame) { + return targetScrollPosition; + } + + CSSPoint geckoScrollPosition = + CSSPoint::FromAppUnits(aFrame->GetScrollPosition()); + + // If the repaint request was triggered due to a previous main-thread scroll + // offset update sent to the APZ, then we don't need to do another scroll here + // and we can just return. + if (!aRequest.GetScrollOffsetUpdated()) { + return geckoScrollPosition; + } + + // If this frame is overflow:hidden, then the expectation is that it was + // sized in a way that respects its scrollable boundaries. For the root + // frame, this means that it cannot be scrolled in such a way that it moves + // the layout viewport. For a non-root frame, this means that it cannot be + // scrolled at all. + // + // In either case, |targetScrollPosition| should be the same as + // |geckoScrollPosition| here. + // + // However, this is slightly racy. We query the overflow property of the + // scroll frame at the time the repaint request arrives at the main thread + // (i.e., right now), but APZ made the decision of whether or not to allow + // scrolling based on the information it had at the time it processed the + // scroll event. The overflow property could have changed at some time + // between the two events and so APZ may have computed a scrollable region + // that is larger than what is actually allowed. + // + // Currently, we allow the scroll position to change even though the frame is + // overflow:hidden (that is, we take |targetScrollPosition|). If this turns + // out to be problematic, an alternative solution would be to ignore the + // scroll position change (that is, use |geckoScrollPosition|). + if (aFrame->GetScrollStyles().mVertical == StyleOverflow::Hidden && + targetScrollPosition.y != geckoScrollPosition.y) { + NS_WARNING( + nsPrintfCString( + "APZCCH: targetScrollPosition.y (%f) != geckoScrollPosition.y (%f)", + targetScrollPosition.y.value, geckoScrollPosition.y.value) + .get()); + } + if (aFrame->GetScrollStyles().mHorizontal == StyleOverflow::Hidden && + targetScrollPosition.x != geckoScrollPosition.x) { + NS_WARNING( + nsPrintfCString( + "APZCCH: targetScrollPosition.x (%f) != geckoScrollPosition.x (%f)", + targetScrollPosition.x.value, geckoScrollPosition.x.value) + .get()); + } + + // If the scrollable frame is currently in the middle of an async or smooth + // scroll then we don't want to interrupt it (see bug 961280). + // Also if the scrollable frame got a scroll request from a higher priority + // origin since the last layers update, then we don't want to push our scroll + // request because we'll clobber that one, which is bad. + bool scrollInProgress = APZCCallbackHelper::IsScrollInProgress(aFrame); + if (!scrollInProgress) { + ScrollSnapTargetIds snapTargetIds = aRequest.GetLastSnapTargetIds(); + aFrame->ScrollToCSSPixelsForApz(targetScrollPosition, + std::move(snapTargetIds)); + geckoScrollPosition = CSSPoint::FromAppUnits(aFrame->GetScrollPosition()); + aSuccessOut = true; + } + // Return the final scroll position after setting it so that anything that + // relies on it can have an accurate value. Note that even if we set it above + // re-querying it is a good idea because it may have gotten clamped or + // rounded. + return geckoScrollPosition; +} + +/** + * Scroll the scroll frame associated with |aContent| to the scroll position + * requested in |aRequest|. + * + * Any difference between the requested and actual scroll positions is used to + * update the callback-transform stored on the content, and return a new + * display port. + */ +static DisplayPortMargins ScrollFrame(nsIContent* aContent, + const RepaintRequest& aRequest) { + // Scroll the window to the desired spot + nsIScrollableFrame* sf = + nsLayoutUtils::FindScrollableFrameFor(aRequest.GetScrollId()); + if (sf) { + sf->ResetScrollInfoIfNeeded(aRequest.GetScrollGeneration(), + aRequest.GetScrollGenerationOnApz(), + aRequest.GetScrollAnimationType(), + nsIScrollableFrame::InScrollingGesture( + aRequest.IsInScrollingGesture())); + sf->SetScrollableByAPZ(!aRequest.IsScrollInfoLayer()); + if (sf->IsRootScrollFrameOfDocument()) { + if (!APZCCallbackHelper::IsScrollInProgress(sf)) { + APZCCH_LOG("Setting VV offset to %s\n", + ToString(aRequest.GetVisualScrollOffset()).c_str()); + if (sf->SetVisualViewportOffset( + CSSPoint::ToAppUnits(aRequest.GetVisualScrollOffset()), + /* aRepaint = */ false)) { + // sf can't be destroyed if SetVisualViewportOffset returned true. + sf->MarkEverScrolled(); + } + } + } + } + // sf might have been destroyed by the call to SetVisualViewportOffset, so + // re-get it. + sf = nsLayoutUtils::FindScrollableFrameFor(aRequest.GetScrollId()); + bool scrollUpdated = false; + auto displayPortMargins = + DisplayPortMargins::ForScrollFrame(sf, aRequest.GetDisplayPortMargins()); + CSSPoint apzScrollOffset = aRequest.GetVisualScrollOffset(); + CSSPoint actualScrollOffset = ScrollFrameTo(sf, aRequest, scrollUpdated); + CSSPoint scrollDelta = apzScrollOffset - actualScrollOffset; + + if (scrollUpdated) { + if (aRequest.IsScrollInfoLayer()) { + // In cases where the APZ scroll offset is different from the content + // scroll offset, we want to interpret the margins as relative to the APZ + // scroll offset except when the frame is not scrollable by APZ. + // Therefore, if the layer is a scroll info layer, we leave the margins + // as-is and they will be interpreted as relative to the content scroll + // offset. + if (nsIFrame* frame = aContent->GetPrimaryFrame()) { + frame->SchedulePaint(); + } + } else { + // Correct the display port due to the difference between the requested + // and actual scroll offsets. + displayPortMargins = + DisplayPortMargins::FromAPZ(aRequest.GetDisplayPortMargins(), + apzScrollOffset, actualScrollOffset); + } + } else if (aRequest.IsRootContent() && + apzScrollOffset != aRequest.GetLayoutScrollOffset()) { + // APZ uses the visual viewport's offset to calculate where to place the + // display port, so the display port is misplaced when a pinch zoom occurs. + // + // We need to force a display port adjustment in the following paint to + // account for a difference between the requested and actual scroll + // offsets in repaints requested by + // AsyncPanZoomController::NotifyLayersUpdated. + displayPortMargins = DisplayPortMargins::FromAPZ( + aRequest.GetDisplayPortMargins(), apzScrollOffset, actualScrollOffset); + } else { + // For whatever reason we couldn't update the scroll offset on the scroll + // frame, which means the data APZ used for its displayport calculation is + // stale. Fall back to a sane default behaviour. Note that we don't + // tile-align the recentered displayport because tile-alignment depends on + // the scroll position, and the scroll position here is out of our control. + // See bug 966507 comment 21 for a more detailed explanation. + displayPortMargins = DisplayPortMargins::ForScrollFrame( + sf, RecenterDisplayPort(aRequest.GetDisplayPortMargins())); + } + + // APZ transforms inputs assuming we applied the exact scroll offset it + // requested (|apzScrollOffset|). Since we may not have, record the difference + // between what APZ asked for and what we actually applied, and apply it to + // input events to compensate. + // Note that if the main-thread had a change in its scroll position, we don't + // want to record that difference here, because it can be large and throw off + // input events by a large amount. It is also going to be transient, because + // any main-thread scroll position change will be synced to APZ and we will + // get another repaint request when APZ confirms. In the interval while this + // is happening we can just leave the callback transform as it was. + bool mainThreadScrollChanged = + sf && sf->CurrentScrollGeneration() != aRequest.GetScrollGeneration() && + nsLayoutUtils::CanScrollOriginClobberApz(sf->LastScrollOrigin()); + if (aContent && !mainThreadScrollChanged) { + aContent->SetProperty(nsGkAtoms::apzCallbackTransform, + new CSSPoint(scrollDelta), + nsINode::DeleteProperty<CSSPoint>); + } + + return displayPortMargins; +} + +static void SetDisplayPortMargins(PresShell* aPresShell, nsIContent* aContent, + const DisplayPortMargins& aDisplayPortMargins, + CSSSize aDisplayPortBase) { + if (!aContent) { + return; + } + + bool hadDisplayPort = DisplayPortUtils::HasDisplayPort(aContent); + if (MOZ_LOG_TEST(sDisplayportLog, LogLevel::Debug)) { + if (!hadDisplayPort) { + mozilla::layers::ScrollableLayerGuid::ViewID viewID = + mozilla::layers::ScrollableLayerGuid::NULL_SCROLL_ID; + nsLayoutUtils::FindIDFor(aContent, &viewID); + MOZ_LOG( + sDisplayportLog, LogLevel::Debug, + ("APZCCH installing displayport margins %s on scrollId=%" PRIu64 "\n", + ToString(aDisplayPortMargins).c_str(), viewID)); + } + } + DisplayPortUtils::SetDisplayPortMargins( + aContent, aPresShell, aDisplayPortMargins, + hadDisplayPort ? DisplayPortUtils::ClearMinimalDisplayPortProperty::No + : DisplayPortUtils::ClearMinimalDisplayPortProperty::Yes, + 0); + if (!hadDisplayPort) { + DisplayPortUtils::SetZeroMarginDisplayPortOnAsyncScrollableAncestors( + aContent->GetPrimaryFrame()); + } + + nsRect base(0, 0, aDisplayPortBase.width * AppUnitsPerCSSPixel(), + aDisplayPortBase.height * AppUnitsPerCSSPixel()); + DisplayPortUtils::SetDisplayPortBaseIfNotSet(aContent, base); +} + +static void SetPaintRequestTime(nsIContent* aContent, + const TimeStamp& aPaintRequestTime) { + aContent->SetProperty(nsGkAtoms::paintRequestTime, + new TimeStamp(aPaintRequestTime), + nsINode::DeleteProperty<TimeStamp>); +} + +void APZCCallbackHelper::NotifyLayerTransforms( + const nsTArray<MatrixMessage>& aTransforms) { + MOZ_ASSERT(NS_IsMainThread()); + for (const MatrixMessage& msg : aTransforms) { + BrowserParent* parent = + BrowserParent::GetBrowserParentFromLayersId(msg.GetLayersId()); + if (parent) { + parent->SetChildToParentConversionMatrix( + ViewAs<LayoutDeviceToLayoutDeviceMatrix4x4>( + msg.GetMatrix(), + PixelCastJustification::ContentProcessIsLayerInUiProcess), + msg.GetTopLevelViewportVisibleRectInBrowserCoords()); + } + } +} + +void APZCCallbackHelper::UpdateRootFrame(const RepaintRequest& aRequest) { + if (aRequest.GetScrollId() == ScrollableLayerGuid::NULL_SCROLL_ID) { + return; + } + RefPtr<nsIContent> content = + nsLayoutUtils::FindContentFor(aRequest.GetScrollId()); + if (!content) { + return; + } + + RefPtr<PresShell> presShell = GetPresShell(content); + if (!presShell || aRequest.GetPresShellId() != presShell->GetPresShellId()) { + return; + } + + APZCCH_LOG("Handling request %s\n", ToString(aRequest).c_str()); + if (nsLayoutUtils::AllowZoomingForDocument(presShell->GetDocument()) && + aRequest.GetAsyncZoom().scale != 1.0) { + // If zooming is disabled then we don't really want to let APZ fiddle + // with these things. In theory setting the resolution here should be a + // no-op, but setting the visual viewport size is bad because it can cause a + // stale value to be returned by window.innerWidth/innerHeight (see bug + // 1187792). + + float presShellResolution = presShell->GetResolution(); + + // If the pres shell resolution has changed on the content side side + // the time this repaint request was fired, consider this request out of + // date and drop it; setting a zoom based on the out-of-date resolution can + // have the effect of getting us stuck with the stale resolution. + // One might think that if the last ResolutionChangeOrigin was apz then the + // pres shell resolutions should match but + // that is not the case. We can get multiple repaint requests that has the + // same pres shell resolution (because apz didn't receive a content layers + // update inbetween) if the first has async zoom we apply that and chance + // the content pres shell resolution and thus when handling the second + // repaint request the pres shell resolution won't match. So that's why we + // also check if the last resolution change origin was apz (aka 'us'). + if (!FuzzyEqualsMultiplicative(presShellResolution, + aRequest.GetPresShellResolution()) && + presShell->GetLastResolutionChangeOrigin() != + ResolutionChangeOrigin::Apz) { + return; + } + + // The pres shell resolution is updated by the the async zoom since the + // last paint. + // We want to calculate the new presshell resolution as + // |aRequest.GetPresShellResolution() * aRequest.GetAsyncZoom()| but that + // calculation can lead to small inaccuracies due to limited floating point + // precision. Specifically, + // clang-format off + // asyncZoom = zoom / layerPixelsPerCSSPixel + // = zoom / (devPixelsPerCSSPixel * cumulativeResolution) + // clang-format on + // Since this is a root frame we generally do not allow css transforms to + // scale it, so it is very likely that cumulativeResolution == + // presShellResoluion. So + // clang-format off + // newPresShellResoluion = presShellResoluion * asyncZoom + // = presShellResoluion * zoom / (devPixelsPerCSSPixel * presShellResoluion) + // = zoom / devPixelsPerCSSPixel + // clang-format on + // However, we want to keep the calculation general and so we do not assume + // presShellResoluion == cumulativeResolution, but rather factor those + // values out so they cancel and the floating point division has a very high + // probability of being exactly 1. + presShellResolution = + (aRequest.GetPresShellResolution() / + aRequest.GetCumulativeResolution().scale) * + (aRequest.GetZoom() / aRequest.GetDevPixelsPerCSSPixel()).scale; + presShell->SetResolutionAndScaleTo(presShellResolution, + ResolutionChangeOrigin::Apz); + + // Changing the resolution will trigger a reflow which will cause the + // main-thread scroll position to be realigned in layer pixels. This + // (subpixel) scroll mutation can trigger a scroll update to APZ which + // is undesirable. Instead of having that happen as part of the post-reflow + // code, we force it to happen here with ScrollOrigin::Apz so that it + // doesn't trigger a scroll update to APZ. + nsIScrollableFrame* sf = + nsLayoutUtils::FindScrollableFrameFor(aRequest.GetScrollId()); + CSSPoint currentScrollPosition = + CSSPoint::FromAppUnits(sf->GetScrollPosition()); + ScrollSnapTargetIds snapTargetIds = aRequest.GetLastSnapTargetIds(); + sf->ScrollToCSSPixelsForApz(currentScrollPosition, + std::move(snapTargetIds)); + } + + // Do this as late as possible since scrolling can flush layout. It also + // adjusts the display port margins, so do it before we set those. + DisplayPortMargins displayPortMargins = ScrollFrame(content, aRequest); + + SetDisplayPortMargins(presShell, content, displayPortMargins, + aRequest.CalculateCompositedSizeInCssPixels()); + SetPaintRequestTime(content, aRequest.GetPaintRequestTime()); +} + +void APZCCallbackHelper::UpdateSubFrame(const RepaintRequest& aRequest) { + if (aRequest.GetScrollId() == ScrollableLayerGuid::NULL_SCROLL_ID) { + return; + } + RefPtr<nsIContent> content = + nsLayoutUtils::FindContentFor(aRequest.GetScrollId()); + if (!content) { + return; + } + + // We don't currently support zooming for subframes, so nothing extra + // needs to be done beyond the tasks common to this and UpdateRootFrame. + DisplayPortMargins displayPortMargins = ScrollFrame(content, aRequest); + if (RefPtr<PresShell> presShell = GetPresShell(content)) { + SetDisplayPortMargins(presShell, content, displayPortMargins, + aRequest.CalculateCompositedSizeInCssPixels()); + } + SetPaintRequestTime(content, aRequest.GetPaintRequestTime()); +} + +bool APZCCallbackHelper::GetOrCreateScrollIdentifiers( + nsIContent* aContent, uint32_t* aPresShellIdOut, + ScrollableLayerGuid::ViewID* aViewIdOut) { + if (!aContent) { + return false; + } + *aViewIdOut = nsLayoutUtils::FindOrCreateIDFor(aContent); + if (PresShell* presShell = GetPresShell(aContent)) { + *aPresShellIdOut = presShell->GetPresShellId(); + return true; + } + return false; +} + +void APZCCallbackHelper::InitializeRootDisplayport(PresShell* aPresShell) { + // Create a view-id and set a zero-margin displayport for the root element + // of the root document in the chrome process. This ensures that the scroll + // frame for this element gets an APZC, which in turn ensures that all content + // in the chrome processes is covered by an APZC. + // The displayport is zero-margin because this element is generally not + // actually scrollable (if it is, APZC will set proper margins when it's + // scrolled). + if (!aPresShell) { + return; + } + + MOZ_ASSERT(aPresShell->GetDocument()); + nsIContent* content = aPresShell->GetDocument()->GetDocumentElement(); + if (!content) { + return; + } + + uint32_t presShellId; + ScrollableLayerGuid::ViewID viewId; + if (APZCCallbackHelper::GetOrCreateScrollIdentifiers(content, &presShellId, + &viewId)) { + MOZ_LOG( + sDisplayportLog, LogLevel::Debug, + ("Initializing root displayport on scrollId=%" PRIu64 "\n", viewId)); + Maybe<nsRect> baseRect = + DisplayPortUtils::GetRootDisplayportBase(aPresShell); + if (baseRect) { + DisplayPortUtils::SetDisplayPortBaseIfNotSet(content, *baseRect); + } + + DisplayPortUtils::SetDisplayPortMargins( + content, aPresShell, DisplayPortMargins::Empty(content), + DisplayPortUtils::ClearMinimalDisplayPortProperty::Yes, 0); + DisplayPortUtils::SetZeroMarginDisplayPortOnAsyncScrollableAncestors( + content->GetPrimaryFrame()); + } +} + +nsPresContext* APZCCallbackHelper::GetPresContextForContent( + nsIContent* aContent) { + dom::Document* doc = aContent->GetComposedDoc(); + if (!doc) { + return nullptr; + } + PresShell* presShell = doc->GetPresShell(); + if (!presShell) { + return nullptr; + } + return presShell->GetPresContext(); +} + +PresShell* APZCCallbackHelper::GetRootContentDocumentPresShellForContent( + nsIContent* aContent) { + nsPresContext* context = GetPresContextForContent(aContent); + if (!context) { + return nullptr; + } + context = context->GetInProcessRootContentDocumentPresContext(); + if (!context) { + return nullptr; + } + return context->PresShell(); +} + +nsEventStatus APZCCallbackHelper::DispatchWidgetEvent(WidgetGUIEvent& aEvent) { + nsEventStatus status = nsEventStatus_eConsumeNoDefault; + if (aEvent.mWidget) { + aEvent.mWidget->DispatchEvent(&aEvent, status); + } + return status; +} + +nsEventStatus APZCCallbackHelper::DispatchSynthesizedMouseEvent( + EventMessage aMsg, const LayoutDevicePoint& aRefPoint, Modifiers aModifiers, + int32_t aClickCount, nsIWidget* aWidget) { + MOZ_ASSERT(aMsg == eMouseMove || aMsg == eMouseDown || aMsg == eMouseUp || + aMsg == eMouseLongTap); + + WidgetMouseEvent event(true, aMsg, aWidget, WidgetMouseEvent::eReal, + WidgetMouseEvent::eNormal); + event.mRefPoint = LayoutDeviceIntPoint::Truncate(aRefPoint.x, aRefPoint.y); + event.mButton = MouseButton::ePrimary; + event.mButtons |= MouseButtonsFlag::ePrimaryFlag; + event.mInputSource = dom::MouseEvent_Binding::MOZ_SOURCE_TOUCH; + if (aMsg == eMouseLongTap) { + event.mFlags.mOnlyChromeDispatch = true; + } + if (aMsg != eMouseMove) { + event.mClickCount = aClickCount; + } + event.mModifiers = aModifiers; + // Real touch events will generate corresponding pointer events. We set + // convertToPointer to false to prevent the synthesized mouse events generate + // pointer events again. + event.convertToPointer = false; + return DispatchWidgetEvent(event); +} + +PreventDefaultResult APZCCallbackHelper::DispatchMouseEvent( + PresShell* aPresShell, const nsString& aType, const CSSPoint& aPoint, + int32_t aButton, int32_t aClickCount, int32_t aModifiers, + unsigned short aInputSourceArg, uint32_t aPointerId) { + NS_ENSURE_TRUE(aPresShell, PreventDefaultResult::ByContent); + + PreventDefaultResult preventDefaultResult; + nsContentUtils::SendMouseEvent( + aPresShell, aType, aPoint.x, aPoint.y, aButton, + nsIDOMWindowUtils::MOUSE_BUTTONS_NOT_SPECIFIED, aClickCount, aModifiers, + /* aIgnoreRootScrollFrame = */ false, 0, aInputSourceArg, aPointerId, + false, &preventDefaultResult, false, + /* aIsWidgetEventSynthesized = */ false); + return preventDefaultResult; +} + +void APZCCallbackHelper::FireSingleTapEvent(const LayoutDevicePoint& aPoint, + Modifiers aModifiers, + int32_t aClickCount, + nsIWidget* aWidget) { + if (aWidget->Destroyed()) { + return; + } + APZCCH_LOG("Dispatching single-tap component events to %s\n", + ToString(aPoint).c_str()); + DispatchSynthesizedMouseEvent(eMouseMove, aPoint, aModifiers, aClickCount, + aWidget); + DispatchSynthesizedMouseEvent(eMouseDown, aPoint, aModifiers, aClickCount, + aWidget); + DispatchSynthesizedMouseEvent(eMouseUp, aPoint, aModifiers, aClickCount, + aWidget); +} + +static dom::Element* GetDisplayportElementFor( + nsIScrollableFrame* aScrollableFrame) { + if (!aScrollableFrame) { + return nullptr; + } + nsIFrame* scrolledFrame = aScrollableFrame->GetScrolledFrame(); + if (!scrolledFrame) { + return nullptr; + } + // |scrolledFrame| should at this point be the root content frame of the + // nearest ancestor scrollable frame. The element corresponding to this + // frame should be the one with the displayport set on it, so find that + // element and return it. + nsIContent* content = scrolledFrame->GetContent(); + MOZ_ASSERT(content->IsElement()); // roc says this must be true + return content->AsElement(); +} + +static dom::Element* GetRootDocumentElementFor(nsIWidget* aWidget) { + // This returns the root element that ChromeProcessController sets the + // displayport on during initialization. + if (nsView* view = nsView::GetViewFor(aWidget)) { + if (PresShell* presShell = view->GetPresShell()) { + MOZ_ASSERT(presShell->GetDocument()); + return presShell->GetDocument()->GetDocumentElement(); + } + } + return nullptr; +} + +namespace { + +using FrameForPointOption = nsLayoutUtils::FrameForPointOption; + +// Determine the scrollable target frame for the given point and add it to +// the target list. If the frame doesn't have a displayport, set one. +// Return whether or not the frame had a displayport that has already been +// painted (in this case, the caller can send the SetTargetAPZC notification +// right away, rather than waiting for a transaction to propagate the +// displayport to APZ first). +static bool PrepareForSetTargetAPZCNotification( + nsIWidget* aWidget, const LayersId& aLayersId, nsIFrame* aRootFrame, + const LayoutDeviceIntPoint& aRefPoint, + nsTArray<ScrollableLayerGuid>* aTargets) { + ScrollableLayerGuid guid(aLayersId, 0, ScrollableLayerGuid::NULL_SCROLL_ID); + RelativeTo relativeTo{aRootFrame, ViewportType::Visual}; + nsPoint point = nsLayoutUtils::GetEventCoordinatesRelativeTo( + aWidget, aRefPoint, relativeTo); + nsIFrame* target = nsLayoutUtils::GetFrameForPoint(relativeTo, point); + nsIScrollableFrame* scrollAncestor = + target ? nsLayoutUtils::GetAsyncScrollableAncestorFrame(target) + : aRootFrame->PresShell()->GetRootScrollFrameAsScrollable(); + + // Assuming that if there's no scrollAncestor, there's already a displayPort. + nsCOMPtr<dom::Element> dpElement = + scrollAncestor ? GetDisplayportElementFor(scrollAncestor) + : GetRootDocumentElementFor(aWidget); + + if (MOZ_LOG_TEST(sApzHlpLog, LogLevel::Debug)) { + nsAutoString dpElementDesc; + if (dpElement) { + dpElement->Describe(dpElementDesc); + } + APZCCH_LOG("For event at %s found scrollable element %p (%s)\n", + ToString(aRefPoint).c_str(), dpElement.get(), + NS_LossyConvertUTF16toASCII(dpElementDesc).get()); + } + + bool guidIsValid = APZCCallbackHelper::GetOrCreateScrollIdentifiers( + dpElement, &(guid.mPresShellId), &(guid.mScrollId)); + aTargets->AppendElement(guid); + + if (!guidIsValid) { + return false; + } + if (DisplayPortUtils::HasNonMinimalNonZeroDisplayPort(dpElement)) { + // If the element has a displayport but it hasn't been painted yet, + // we want the caller to wait for the paint to happen, but we don't + // need to set the displayport here since it's already been set. + return !DisplayPortUtils::HasPaintedDisplayPort(dpElement); + } + + if (!scrollAncestor) { + // This can happen if the document element gets swapped out after + // ChromeProcessController runs InitializeRootDisplayport. In this case + // let's try to set a displayport again and bail out on this operation. + APZCCH_LOG("Widget %p's document element %p didn't have a displayport\n", + aWidget, dpElement.get()); + APZCCallbackHelper::InitializeRootDisplayport(aRootFrame->PresShell()); + return false; + } + + APZCCH_LOG("%p didn't have a displayport, so setting one...\n", + dpElement.get()); + MOZ_LOG(sDisplayportLog, LogLevel::Debug, + ("Activating displayport on scrollId=%" PRIu64 " for SetTargetAPZC\n", + guid.mScrollId)); + bool activated = DisplayPortUtils::CalculateAndSetDisplayPortMargins( + scrollAncestor, DisplayPortUtils::RepaintMode::Repaint); + if (!activated) { + return false; + } + + nsIFrame* frame = do_QueryFrame(scrollAncestor); + DisplayPortUtils::SetZeroMarginDisplayPortOnAsyncScrollableAncestors(frame); + + return !DisplayPortUtils::HasPaintedDisplayPort(dpElement); +} + +static void SendLayersDependentApzcTargetConfirmation( + nsIWidget* aWidget, uint64_t aInputBlockId, + nsTArray<ScrollableLayerGuid>&& aTargets) { + WindowRenderer* renderer = aWidget->GetWindowRenderer(); + if (!renderer) { + return; + } + + if (WebRenderLayerManager* wrlm = renderer->AsWebRender()) { + if (WebRenderBridgeChild* wrbc = wrlm->WrBridge()) { + wrbc->SendSetConfirmedTargetAPZC(aInputBlockId, aTargets); + } + return; + } +} + +} // namespace + +DisplayportSetListener::DisplayportSetListener( + nsIWidget* aWidget, nsPresContext* aPresContext, + const uint64_t& aInputBlockId, nsTArray<ScrollableLayerGuid>&& aTargets) + : ManagedPostRefreshObserver(aPresContext), + mWidget(aWidget), + mInputBlockId(aInputBlockId), + mTargets(std::move(aTargets)) { + MOZ_ASSERT(!mAction, "Setting Action twice"); + mAction = [instance = MOZ_KnownLive(this)](bool aWasCanceled) { + instance->OnPostRefresh(); + return Unregister::Yes; + }; +} + +DisplayportSetListener::~DisplayportSetListener() = default; + +void DisplayportSetListener::Register() { + APZCCH_LOG("DisplayportSetListener::Register\n"); + mPresContext->RegisterManagedPostRefreshObserver(this); +} + +void DisplayportSetListener::OnPostRefresh() { + APZCCH_LOG("Got refresh, sending target APZCs for input block %" PRIu64 "\n", + mInputBlockId); + SendLayersDependentApzcTargetConfirmation(mWidget, mInputBlockId, + std::move(mTargets)); +} + +already_AddRefed<DisplayportSetListener> +APZCCallbackHelper::SendSetTargetAPZCNotification(nsIWidget* aWidget, + dom::Document* aDocument, + const WidgetGUIEvent& aEvent, + const LayersId& aLayersId, + uint64_t aInputBlockId) { + if (!aWidget || !aDocument) { + return nullptr; + } + if (aInputBlockId == sLastTargetAPZCNotificationInputBlock) { + // We have already confirmed the target APZC for a previous event of this + // input block. If we activated a scroll frame for this input block, + // sending another target APZC confirmation would be harmful, as it might + // race the original confirmation (which needs to go through a layers + // transaction). + APZCCH_LOG("Not resending target APZC confirmation for input block %" PRIu64 + "\n", + aInputBlockId); + return nullptr; + } + sLastTargetAPZCNotificationInputBlock = aInputBlockId; + if (PresShell* presShell = aDocument->GetPresShell()) { + if (nsIFrame* rootFrame = presShell->GetRootFrame()) { + bool waitForRefresh = false; + nsTArray<ScrollableLayerGuid> targets; + + if (const WidgetTouchEvent* touchEvent = aEvent.AsTouchEvent()) { + for (size_t i = 0; i < touchEvent->mTouches.Length(); i++) { + waitForRefresh |= PrepareForSetTargetAPZCNotification( + aWidget, aLayersId, rootFrame, touchEvent->mTouches[i]->mRefPoint, + &targets); + } + } else if (const WidgetWheelEvent* wheelEvent = aEvent.AsWheelEvent()) { + waitForRefresh = PrepareForSetTargetAPZCNotification( + aWidget, aLayersId, rootFrame, wheelEvent->mRefPoint, &targets); + } else if (const WidgetMouseEvent* mouseEvent = aEvent.AsMouseEvent()) { + waitForRefresh = PrepareForSetTargetAPZCNotification( + aWidget, aLayersId, rootFrame, mouseEvent->mRefPoint, &targets); + } + // TODO: Do other types of events need to be handled? + + if (!targets.IsEmpty()) { + if (waitForRefresh) { + APZCCH_LOG( + "At least one target got a new displayport, need to wait for " + "refresh\n"); + return MakeAndAddRef<DisplayportSetListener>( + aWidget, presShell->GetPresContext(), aInputBlockId, + std::move(targets)); + } + APZCCH_LOG("Sending target APZCs for input block %" PRIu64 "\n", + aInputBlockId); + aWidget->SetConfirmedTargetAPZC(aInputBlockId, targets); + } + } + } + return nullptr; +} + +void APZCCallbackHelper::NotifyMozMouseScrollEvent( + const ScrollableLayerGuid::ViewID& aScrollId, const nsString& aEvent) { + nsCOMPtr<nsIContent> targetContent = nsLayoutUtils::FindContentFor(aScrollId); + if (!targetContent) { + return; + } + RefPtr<dom::Document> ownerDoc = targetContent->OwnerDoc(); + if (!ownerDoc) { + return; + } + + nsContentUtils::DispatchEventOnlyToChrome(ownerDoc, targetContent, aEvent, + CanBubble::eYes, Cancelable::eYes); +} + +void APZCCallbackHelper::NotifyFlushComplete(PresShell* aPresShell) { + MOZ_ASSERT(NS_IsMainThread()); + // In some cases, flushing the APZ state to the main thread doesn't actually + // trigger a flush and repaint (this is an intentional optimization - the + // stuff visible to the user is still correct). However, reftests update their + // snapshot based on invalidation events that are emitted during paints, + // so we ensure that we kick off a paint when an APZ flush is done. Note that + // only chrome/testing code can trigger this behaviour. + if (aPresShell && aPresShell->GetRootFrame()) { + aPresShell->GetRootFrame()->SchedulePaint(nsIFrame::PAINT_DEFAULT, false); + } + + nsCOMPtr<nsIObserverService> observerService = + mozilla::services::GetObserverService(); + MOZ_ASSERT(observerService); + observerService->NotifyObservers(nullptr, "apz-repaints-flushed", nullptr); +} + +/* static */ +bool APZCCallbackHelper::IsScrollInProgress(nsIScrollableFrame* aFrame) { + using AnimationState = nsIScrollableFrame::AnimationState; + + return aFrame->ScrollAnimationState().contains(AnimationState::MainThread) || + nsLayoutUtils::CanScrollOriginClobberApz(aFrame->LastScrollOrigin()); +} + +/* static */ +void APZCCallbackHelper::NotifyAsyncScrollbarDragInitiated( + uint64_t aDragBlockId, const ScrollableLayerGuid::ViewID& aScrollId, + ScrollDirection aDirection) { + MOZ_ASSERT(NS_IsMainThread()); + if (nsIScrollableFrame* scrollFrame = + nsLayoutUtils::FindScrollableFrameFor(aScrollId)) { + scrollFrame->AsyncScrollbarDragInitiated(aDragBlockId, aDirection); + } +} + +/* static */ +void APZCCallbackHelper::NotifyAsyncScrollbarDragRejected( + const ScrollableLayerGuid::ViewID& aScrollId) { + MOZ_ASSERT(NS_IsMainThread()); + if (nsIScrollableFrame* scrollFrame = + nsLayoutUtils::FindScrollableFrameFor(aScrollId)) { + scrollFrame->AsyncScrollbarDragRejected(); + } +} + +/* static */ +void APZCCallbackHelper::NotifyAsyncAutoscrollRejected( + const ScrollableLayerGuid::ViewID& aScrollId) { + MOZ_ASSERT(NS_IsMainThread()); + nsCOMPtr<nsIObserverService> observerService = + mozilla::services::GetObserverService(); + MOZ_ASSERT(observerService); + + nsAutoString data; + data.AppendInt(aScrollId); + observerService->NotifyObservers(nullptr, "autoscroll-rejected-by-apz", + data.get()); +} + +/* static */ +void APZCCallbackHelper::CancelAutoscroll( + const ScrollableLayerGuid::ViewID& aScrollId) { + MOZ_ASSERT(NS_IsMainThread()); + nsCOMPtr<nsIObserverService> observerService = + mozilla::services::GetObserverService(); + MOZ_ASSERT(observerService); + + nsAutoString data; + data.AppendInt(aScrollId); + observerService->NotifyObservers(nullptr, "apz:cancel-autoscroll", + data.get()); +} + +/* static */ +void APZCCallbackHelper::NotifyScaleGestureComplete( + const nsCOMPtr<nsIWidget>& aWidget, float aScale) { + MOZ_ASSERT(NS_IsMainThread()); + + if (nsView* view = nsView::GetViewFor(aWidget)) { + if (PresShell* presShell = view->GetPresShell()) { + dom::Document* doc = presShell->GetDocument(); + MOZ_ASSERT(doc); + if (nsPIDOMWindowInner* win = doc->GetInnerWindow()) { + dom::AutoJSAPI jsapi; + if (!jsapi.Init(win)) { + return; + } + + JSContext* cx = jsapi.cx(); + JS::Rooted<JS::Value> detail(cx, JS::Float32Value(aScale)); + RefPtr<dom::CustomEvent> event = + NS_NewDOMCustomEvent(doc, nullptr, nullptr); + event->InitCustomEvent(cx, u"MozScaleGestureComplete"_ns, + /* CanBubble */ true, + /* Cancelable */ false, detail); + event->SetTrusted(true); + AsyncEventDispatcher* dispatcher = new AsyncEventDispatcher(doc, event); + dispatcher->mOnlyChromeDispatch = ChromeOnlyDispatch::eYes; + + dispatcher->PostDOMEvent(); + } + } + } +} + +/* static */ +void APZCCallbackHelper::NotifyPinchGesture( + PinchGestureInput::PinchGestureType aType, + const LayoutDevicePoint& aFocusPoint, LayoutDeviceCoord aSpanChange, + Modifiers aModifiers, const nsCOMPtr<nsIWidget>& aWidget) { + APZCCH_LOG("APZCCallbackHelper dispatching pinch gesture\n"); + EventMessage msg; + switch (aType) { + case PinchGestureInput::PINCHGESTURE_START: + msg = eMagnifyGestureStart; + break; + case PinchGestureInput::PINCHGESTURE_SCALE: + msg = eMagnifyGestureUpdate; + break; + case PinchGestureInput::PINCHGESTURE_FINGERLIFTED: + case PinchGestureInput::PINCHGESTURE_END: + msg = eMagnifyGesture; + break; + } + + WidgetSimpleGestureEvent event(true, msg, aWidget.get()); + // XXX mDelta for the eMagnifyGesture event is supposed to be the + // cumulative magnification over the entire gesture (per docs in + // SimpleGestureEvent.webidl) but currently APZ just sends us a zero + // aSpanChange for that event, so the mDelta is wrong. Nothing relies + // on that currently, but we might want to fix it at some point. + event.mDelta = aSpanChange; + event.mModifiers = aModifiers; + event.mRefPoint = RoundedToInt(aFocusPoint); + + DispatchWidgetEvent(event); +} + +} // namespace layers +} // namespace mozilla |