Make squashing work with subpixel layout

Source/core/rendering/RenderLayerCompositor.cpp

 /*
  * Copyright (C) 2009, 2010 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1025 matching lines @@
 
     if (!willBeCompositedOrSquashed && layer->parent())
         layer->parent()->setHasNonCompositedChild(true);
 
     descendantHas3DTransform |= anyDescendantHas3DTransform || layer->has3DTransform();
 
     if (overlapMap)
         overlapMap->geometryMap().popMappingsToAncestor(ancestorLayer);
 }
 
-void RenderLayerCompositor::SquashingState::updateSquashingStateForNewMapping(CompositedLayerMappingPtr newCompositedLayerMapping, bool hasNewCompositedLayerMapping, IntPoint newOffsetFromAbsoluteForSquashingCLM)
+void RenderLayerCompositor::SquashingState::updateSquashingStateForNewMapping(CompositedLayerMappingPtr newCompositedLayerMapping, bool hasNewCompositedLayerMapping, LayoutPoint newOffsetFromAbsoluteForSquashingCLM)
 {
     // The most recent backing is done accumulating any more squashing layers.
     if (hasMostRecentMapping)
         mostRecentMapping->finishAccumulatingSquashingLayers(nextSquashedLayerIndex);
 
     nextSquashedLayerIndex = 0;
     mostRecentMapping = newCompositedLayerMapping;
     hasMostRecentMapping = hasNewCompositedLayerMapping;
     offsetFromAbsoluteForSquashingCLM = newOffsetFromAbsoluteForSquashingCLM;
 }
 
-static IntPoint computeOffsetFromAbsolute(RenderLayer* layer)
+static LayoutPoint computeOffsetFromAbsolute(RenderLayer* layer)
 {
     TransformState transformState(TransformState::ApplyTransformDirection, FloatPoint());
     layer->renderer()->mapLocalToContainer(0, transformState, ApplyContainerFlip);
     transformState.flatten();
-    return roundedIntPoint(transformState.lastPlanarPoint());
+    return roundedLayoutPoint(transformState.lastPlanarPoint());
 }
 
 void RenderLayerCompositor::assignLayersToBackings(RenderLayer* updateRoot, bool& layersChanged)
 {
     SquashingState squashingState;
     assignLayersToBackingsInternal(updateRoot, squashingState, layersChanged);
     if (squashingState.hasMostRecentMapping)
         squashingState.mostRecentMapping->finishAccumulatingSquashingLayers(squashingState.nextSquashedLayerIndex);
 }
 
 void RenderLayerCompositor::assignLayersToBackingsInternal(RenderLayer* layer, SquashingState& squashingState, bool& layersChanged)
 {
     if (allocateOrClearCompositedLayerMapping(layer))
         layersChanged = true;
 
     if (layer->reflectionInfo() && updateLayerCompositingState(layer->reflectionInfo()->reflectionLayer()))
         layersChanged = true;
 
     // Add this layer to a squashing backing if needed.
     if (layerSquashingEnabled()) {
         // NOTE: In the future as we generalize this, the background of this layer may need to be assigned to a different backing than
         // the squashed RenderLayer's own primary contents. This would happen when we have a composited negative z-index element that needs
         // to paint on top of the background, but below the layer's main contents. For now, because we always composite layers
         // when they have a composited negative z-index child, such layers will never need squashing so it is not yet an issue.
         if (requiresSquashing(layer->compositingReasons())) {
             // A layer that is squashed with other layers cannot have its own CompositedLayerMapping.
             ASSERT(!layer->hasCompositedLayerMapping());
             ASSERT(squashingState.hasMostRecentMapping);
 
-            IntPoint offsetFromAbsoluteForSquashedLayer = computeOffsetFromAbsolute(layer);
+            LayoutPoint offsetFromAbsoluteForSquashedLayer = computeOffsetFromAbsolute(layer);
 
-            IntSize offsetFromSquashingCLM(offsetFromAbsoluteForSquashedLayer.x() - squashingState.offsetFromAbsoluteForSquashingCLM.x(),
+            LayoutSize offsetFromSquashingCLM(offsetFromAbsoluteForSquashedLayer.x() - squashingState.offsetFromAbsoluteForSquashingCLM.x(),
                 offsetFromAbsoluteForSquashedLayer.y() - squashingState.offsetFromAbsoluteForSquashingCLM.y());
 
             squashingState.mostRecentMapping->addRenderLayerToSquashingGraphicsLayer(layer, offsetFromSquashingCLM, squashingState.nextSquashedLayerIndex);
             squashingState.nextSquashedLayerIndex++;
 
             // FIXME: this can be false sometimes depending on what happens in addRenderLayerToSquashingGraphicsLayer, which should return a bool.
             layersChanged = true;
 
             // FIXME: this should be conditioned on whether this layer actually changed status
             layer->clipper().clearClipRectsIncludingDescendants();
@@ skipping 25 matching lines @@
     if (layer->stackingNode()->isStackingContainer()) {
         RenderLayerStackingNodeIterator iterator(*layer->stackingNode(), NegativeZOrderChildren);
         while (RenderLayerStackingNode* curNode = iterator.next())
             assignLayersToBackingsInternal(curNode->layer(), squashingState, layersChanged);
     }
 
     if (layerSquashingEnabled()) {
         // At this point, if the layer is to be "separately" composited, then its backing becomes the most recent in paint-order.
         if (layer->compositingState() == PaintsIntoOwnBacking || layer->compositingState() == HasOwnBackingButPaintsIntoAncestor) {
             ASSERT(!requiresSquashing(layer->compositingReasons()));
-            IntPoint offsetFromAbsoluteForSquashingCLM = computeOffsetFromAbsolute(layer);
+            LayoutPoint offsetFromAbsoluteForSquashingCLM = computeOffsetFromAbsolute(layer);
             squashingState.updateSquashingStateForNewMapping(layer->compositedLayerMapping(), layer->hasCompositedLayerMapping(), offsetFromAbsoluteForSquashingCLM);
         }
     }
 
     RenderLayerStackingNodeIterator iterator(*layer->stackingNode(), NormalFlowChildren | PositiveZOrderChildren);
     while (RenderLayerStackingNode* curNode = iterator.next())
         assignLayersToBackingsInternal(curNode->layer(), squashingState, layersChanged);
 }
 
 void RenderLayerCompositor::setCompositingParent(RenderLayer* childLayer, RenderLayer* parentLayer)
@@ skipping 1452 matching lines @@
     } else if (graphicsLayer == m_scrollLayer.get()) {
         name = "Frame Scrolling Layer";
     } else {
         ASSERT_NOT_REACHED();
     }
 
     return name;
 }
 
 } // namespace WebCore