Commit ec29ea95 authored by Connor Brewster's avatar Connor Brewster
Browse files

Bug 1178765 - Part 4: Force a display list rebuild when backdrop-filter pref is toggled r=mstange 

Differential Revision: https://phabricator.services.mozilla.com/D40665

--HG--
extra : moz-landing-system : lando
parent 04d4ece0

layout/base/nsLayoutUtils.cpp

+4 −9
Original line number Diff line number Diff line
@@ -3963,16 +3963,11 @@ nsresult nsLayoutUtils::PaintFrame(gfxContext* aRenderingContext, 
      DisplayListChecker toBeMergedChecker;

      DisplayListChecker afterMergeChecker;



      // If we transition between wrapping the RCD-RSF contents into an async

      // zoom container vs. not, we need to rebuild the display list. This only

      // happens when the zooming or container scrolling prefs are toggled

      // (manually by the user, or during test setup).

      // 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.

      bool shouldAttemptPartialUpdate = useRetainedBuilder;

      bool didBuildAsyncZoomContainer =

          builder->ShouldBuildAsyncZoomContainer();

      builder->UpdateShouldBuildAsyncZoomContainer();

      if (builder->ShouldBuildAsyncZoomContainer() !=

          didBuildAsyncZoomContainer) {

      if (builder->ShouldRebuildDisplayListDueToPrefChange()) {

        shouldAttemptPartialUpdate = false;

      }

layout/painting/nsDisplayList.cpp

+34 −1
Original line number Diff line number Diff line
@@ -1273,13 +1273,14 @@ nsDisplayListBuilder::nsDisplayListBuilder(nsIFrame* aReferenceFrame, 
      mPartialBuildFailed(false),

      mIsInActiveDocShell(false),

      mBuildAsyncZoomContainer(false),

      mBuildBackdropRootContainer(false),

      mHitTestArea(),

      mHitTestInfo(CompositorHitTestInvisibleToHit) {

  MOZ_COUNT_CTOR(nsDisplayListBuilder);



  mBuildCompositorHitTestInfo = mAsyncPanZoomEnabled && IsForPainting();



  UpdateShouldBuildAsyncZoomContainer();

  ShouldRebuildDisplayListDueToPrefChange();



  static_assert(

      static_cast<uint32_t>(DisplayItemType::TYPE_MAX) < (1 << TYPE_BITS),
@@ -1509,6 +1510,38 @@ void nsDisplayListBuilder::UpdateShouldBuildAsyncZoomContainer() { 
      !StaticPrefs::layout_scroll_root_frame_containers();

}



void nsDisplayListBuilder::UpdateShouldBuildBackdropRootContainer() {

  mBuildBackdropRootContainer =

      StaticPrefs::layout_css_backdrop_filter_enabled();

}



// Certain prefs may cause display list items to be added or removed when they

// are toggled. In those cases, we need to fully rebuild the display list.

bool nsDisplayListBuilder::ShouldRebuildDisplayListDueToPrefChange() {

  bool shouldRebuild = false;



  // If we transition between wrapping the RCD-RSF contents into an async

  // zoom container vs. not, we need to rebuild the display list. This only

  // happens when the zooming or container scrolling prefs are toggled

  // (manually by the user, or during test setup).

  bool didBuildAsyncZoomContainer = mBuildAsyncZoomContainer;

  UpdateShouldBuildAsyncZoomContainer();

  if (didBuildAsyncZoomContainer != mBuildAsyncZoomContainer) {

    shouldRebuild = true;

  }



  // If backdrop-filter is enabled, backdrop root containers are added to the

  // display list. When the pref is toggled these containers may be added or

  // removed, so the display list should be rebuilt.

  bool didBuildBackdropRootContainer = mBuildBackdropRootContainer;

  UpdateShouldBuildBackdropRootContainer();

  if (didBuildBackdropRootContainer != mBuildBackdropRootContainer) {

    shouldRebuild = true;

  }



  return shouldRebuild;

}



bool nsDisplayListBuilder::MarkOutOfFlowFrameForDisplay(nsIFrame* aDirtyFrame,

                                                        nsIFrame* aFrame) {

  MOZ_ASSERT(aFrame->GetParent() == aDirtyFrame);

layout/painting/nsDisplayList.h

+5 −0
Original line number Diff line number Diff line
@@ -1743,6 +1743,10 @@ class nsDisplayListBuilder { 
  }

  void UpdateShouldBuildAsyncZoomContainer();



  void UpdateShouldBuildBackdropRootContainer();



  bool ShouldRebuildDisplayListDueToPrefChange();



  /**

   * Represents a region composed of frame/rect pairs.

   * WeakFrames are used to track whether a rect still belongs to the region.
@@ -2020,6 +2024,7 @@ class nsDisplayListBuilder { 
  bool mPartialBuildFailed;

  bool mIsInActiveDocShell;

  bool mBuildAsyncZoomContainer;

  bool mBuildBackdropRootContainer;



  nsRect mHitTestArea;

  CompositorHitTestInfo mHitTestInfo;