Commit efa40c64 authored by Jeff Muizelaar's avatar Jeff Muizelaar
Browse files

Bug 1728246. Calculate opaqueness on demand instead of in ComputeVisibility. r=mattwoodrow 

This lets us remove ComputeVisibility()

Differential Revision: https://phabricator.services.mozilla.com/D124106
parent 3401c03f

layout/painting/nsDisplayList.cpp

+1 −14
Original line number Diff line number Diff line
@@ -2304,7 +2304,6 @@ bool nsDisplayList::ComputeVisibilityForSublist( 
    AppendToBottom(item);

  }



  mIsOpaque = !aVisibleRegion->Intersects(aListVisibleBounds);

  return anyVisible;

}
@@ -3076,21 +3075,9 @@ nsRect nsDisplayContainer::GetComponentAlphaBounds( 
static nsRegion GetOpaqueRegion(nsDisplayListBuilder* aBuilder,

                                nsDisplayList* aList,

                                const nsRect& aListBounds) {

  if (aList->IsOpaque()) {

    // Everything within list bounds that's visible is opaque. This is an

    // optimization to avoid calculating the opaque region.

    return aListBounds;

  }



  if (aBuilder->HitTestIsForVisibility()) {

    // If we care about an accurate opaque region, iterate the display list

    // and build up a region of opaque bounds.

  return aList->GetOpaqueRegion(aBuilder);

}



  return nsRegion();

}



nsRegion nsDisplayContainer::GetOpaqueRegion(nsDisplayListBuilder* aBuilder,

                                             bool* aSnap) const {

  return ::mozilla::GetOpaqueRegion(aBuilder, GetChildren(),

layout/painting/nsDisplayList.h

+1 −18
Original line number Diff line number Diff line
@@ -3246,7 +3246,7 @@ class nsDisplayList { 
   * Create an empty list.

   */

  nsDisplayList()

      : mLength(0), mIsOpaque(false), mForceTransparentSurface(false) {

      : mLength(0), mForceTransparentSurface(false) {

    mTop = &mSentinel;

    mSentinel.mAbove = nullptr;

  }
@@ -3256,7 +3256,6 @@ class nsDisplayList { 
  }



  nsDisplayList(nsDisplayList&& aOther) {

    mIsOpaque = aOther.mIsOpaque;

    mForceTransparentSurface = aOther.mForceTransparentSurface;



    if (aOther.mSentinel.mAbove) {
@@ -3278,7 +3277,6 @@ class nsDisplayList { 
        mTop = &mSentinel;

        mLength = 0;

      }

      mIsOpaque = aOther.mIsOpaque;

      mForceTransparentSurface = aOther.mForceTransparentSurface;

    }

    return *this;
@@ -3465,8 +3463,6 @@ class nsDisplayList { 
   * This is also a good place to put ComputeVisibility-related logic

   * that must be applied to every display item. In particular, this

   * sets mVisibleRect on each display item.

   * This sets mIsOpaque if the entire visible area of this list has

   * been removed from aVisibleRegion when we return.

   * This does not remove any items from the list, so we can recompute

   * visiblity with different regions later (see

   * FrameLayerBuilder::DrawPaintedLayer).
@@ -3493,12 +3489,6 @@ class nsDisplayList { 
  bool ComputeVisibilityForRoot(nsDisplayListBuilder* aBuilder,

                                nsRegion* aVisibleRegion);



  /**

   * Returns true if the visible region output from ComputeVisiblity was

   * empty, i.e. everything visible in this list is opaque.

   */

  bool IsOpaque() const { return mIsOpaque; }



  /**

   * Returns true if any display item requires the surface to be transparent.

   */
@@ -3604,12 +3594,9 @@ class nsDisplayList { 
   */

  nsRect GetBuildingRect() const;



  void SetIsOpaque() { mIsOpaque = true; }



  void SetNeedsTransparentSurface() { mForceTransparentSurface = true; }



  void RestoreState() {

    mIsOpaque = false;

    mForceTransparentSurface = false;

  }
@@ -3619,10 +3606,6 @@ class nsDisplayList { 


  uint32_t mLength;



  // This is set to true by FrameLayerBuilder if the final visible region

  // is empty (i.e. everything that was visible is covered by some

  // opaque content in this list).

  bool mIsOpaque;

  // This is set to true by FrameLayerBuilder if any display item in this

  // list needs to force the surface containing this list to be transparent.

  bool mForceTransparentSurface;