Bug 1022612. Part 6: Set the initial mVisibleRect for each display item to the dirty rect when we create the item. r=mattwoodrow

--HG--
extra : rebase_source : 23fb5aefd5de004ca89037724aff7b34e1a5864e

layout/base/nsDisplayList.cpp

@@ -3016,9 +3016,7 @@ nsDisplayWrapList::nsDisplayWrapList(nsDisplayListBuilder* aBuilder,
     mReferenceFrame = 
       aBuilder->FindReferenceFrameFor(GetTransformRootFrame(aFrame));
     mToReferenceFrame = aFrame->GetOffsetToCrossDoc(mReferenceFrame);
-    return;
-  }
-
+  } else {
     // If we're a transformed frame, then we need to find out if we're inside
     // the nsDisplayTransform or outside of it. Frames inside the transform
     // need mReferenceFrame == mFrame, outside needs the next ancestor
@@ -3039,6 +3037,8 @@ nsDisplayWrapList::nsDisplayWrapList(nsDisplayListBuilder* aBuilder,
       mToReferenceFrame = i->ToReferenceFrame();
     }
   }
+  mVisibleRect = aBuilder->GetDirtyRect() + mToReferenceFrame;
+}
 
 nsDisplayWrapList::nsDisplayWrapList(nsDisplayListBuilder* aBuilder,
                                      nsIFrame* aFrame, nsDisplayItem* aItem)
@@ -3056,15 +3056,15 @@ nsDisplayWrapList::nsDisplayWrapList(nsDisplayListBuilder* aBuilder,
     mReferenceFrame = 
       aBuilder->FindReferenceFrameFor(GetTransformRootFrame(aFrame));
     mToReferenceFrame = aFrame->GetOffsetToCrossDoc(mReferenceFrame);
-    return;
-  }
-
+  } else {
     // See the previous nsDisplayWrapList constructor
     if (aItem->Frame() == aFrame) {
       mReferenceFrame = aItem->ReferenceFrame();
       mToReferenceFrame = aItem->ToReferenceFrame();
     }
   }
+  mVisibleRect = aBuilder->GetDirtyRect() + mToReferenceFrame;
+}
 
 nsDisplayWrapList::~nsDisplayWrapList() {
   mList.DeleteAll();
@@ -4336,6 +4336,15 @@ nsDisplayTransform::nsDisplayTransform(nsDisplayListBuilder* aBuilder, nsIFrame
   mStoredList.SetClip(aBuilder, DisplayItemClip::NoClip());
 }
 
+void
+nsDisplayTransform::SetReferenceFrameToAncestor(nsDisplayListBuilder* aBuilder)
+{
+  mReferenceFrame =
+    aBuilder->FindReferenceFrameFor(GetTransformRootFrame(mFrame));
+  mToReferenceFrame = mFrame->GetOffsetToCrossDoc(mReferenceFrame);
+  mVisibleRect = aBuilder->GetDirtyRect() + mToReferenceFrame;
+}
+
 nsDisplayTransform::nsDisplayTransform(nsDisplayListBuilder* aBuilder, nsIFrame *aFrame,
                                        nsDisplayList *aList, uint32_t aIndex) 
   : nsDisplayItem(aBuilder, aFrame)
@@ -4345,9 +4354,7 @@ nsDisplayTransform::nsDisplayTransform(nsDisplayListBuilder* aBuilder, nsIFrame
 {
   MOZ_COUNT_CTOR(nsDisplayTransform);
   NS_ABORT_IF_FALSE(aFrame, "Must have a frame!");
-  mReferenceFrame = 
-    aBuilder->FindReferenceFrameFor(GetTransformRootFrame(aFrame));
-  mToReferenceFrame = aFrame->GetOffsetToCrossDoc(mReferenceFrame);
+  SetReferenceFrameToAncestor(aBuilder);
   mStoredList.SetClip(aBuilder, DisplayItemClip::NoClip());
 }
 
@@ -4360,9 +4367,7 @@ nsDisplayTransform::nsDisplayTransform(nsDisplayListBuilder* aBuilder, nsIFrame
 {
   MOZ_COUNT_CTOR(nsDisplayTransform);
   NS_ABORT_IF_FALSE(aFrame, "Must have a frame!");
-  mReferenceFrame =
-    aBuilder->FindReferenceFrameFor(GetTransformRootFrame(aFrame));
-  mToReferenceFrame = aFrame->GetOffsetToCrossDoc(mReferenceFrame);
+  SetReferenceFrameToAncestor(aBuilder);
   mStoredList.SetClip(aBuilder, DisplayItemClip::NoClip());
 }
 
@@ -5051,7 +5056,7 @@ nsRegion nsDisplayTransform::GetOpaqueRegion(nsDisplayListBuilder *aBuilder,
   if (matrix.Is2D(&matrix2d) &&
       matrix2d.PreservesAxisAlignedRectangles() &&
       mStoredList.GetOpaqueRegion(aBuilder, &tmpSnap).Contains(untransformedVisible)) {
-    result = mVisibleRect;
+    result = mVisibleRect.Intersect(GetBounds(aBuilder, &tmpSnap));
   }
   return result;
 }
@@ -5111,7 +5116,7 @@ nsDisplayTransform::TryMerge(nsDisplayListBuilder *aBuilder,
   /* Now, move everything over to this frame and signal that
    * we merged things!
    */
-  mStoredList.MergeFrom(&static_cast<nsDisplayTransform*>(aItem)->mStoredList);
+  mStoredList.MergeFromTrackingMergedFrames(&static_cast<nsDisplayTransform*>(aItem)->mStoredList);
   return true;
 }
 

layout/base/nsDisplayList.h

@@ -867,8 +867,10 @@ public:
     , mPainted(false)
 #endif
   {
-    mReferenceFrame = aBuilder->FindReferenceFrameFor(aFrame);
-    mToReferenceFrame = aBuilder->ToReferenceFrame(aFrame);
+    mReferenceFrame = aBuilder->FindReferenceFrameFor(aFrame, &mToReferenceFrame);
+    NS_ASSERTION(aBuilder->GetDirtyRect().width >= 0 ||
+                 !aBuilder->IsForPainting(), "dirty rect not set");
+    mVisibleRect = aBuilder->GetDirtyRect() + mToReferenceFrame;
   }
   /**
    * This constructor is only used in rare cases when we need to construct
@@ -2679,14 +2681,11 @@ public:
 protected:
   nsDisplayWrapList() {}
 
-  void MergeFrom(nsDisplayWrapList* aOther)
+  void MergeFromTrackingMergedFrames(nsDisplayWrapList* aOther)
   {
     mList.AppendToBottom(&aOther->mList);
     mBounds.UnionRect(mBounds, aOther->mBounds);
-  }
-  void MergeFromTrackingMergedFrames(nsDisplayWrapList* aOther)
-  {
-    MergeFrom(aOther);
+    mVisibleRect.UnionRect(mVisibleRect, aOther->mVisibleRect);
     mMergedFrames.AppendElement(aOther->mFrame);
     mMergedFrames.MoveElementsFrom(aOther->mMergedFrames);
   }
@@ -3428,6 +3427,8 @@ public:
   virtual void WriteDebugInfo(nsACString& aTo) MOZ_OVERRIDE;
 #endif
 private:
+  void SetReferenceFrameToAncestor(nsDisplayListBuilder* aBuilder);
+
   static gfx3DMatrix GetResultingTransformMatrixInternal(const FrameTransformProperties& aProperties,
                                                          const nsPoint& aOrigin,
                                                          float aAppUnitsPerPixel,