Merge 92255 - Source/WebCore: [Chromium] Use edge-distance method for layer anti-aliasing.

Source/WebCore/platform/graphics/chromium/TiledLayerChromium.cpp

 /*
  * Copyright (C) 2011 Google 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
@@ skipping 20 matching lines @@
 
 #include "GraphicsContext3D.h"
 #include "LayerRendererChromium.h"
 #include "LayerTilerChromium.h"
 #include "TextStream.h"
 #include "cc/CCLayerImpl.h"
 #include "cc/CCTiledLayerImpl.h"
 #include <wtf/CurrentTime.h>
 
 // Start tiling when the width and height of a layer are larger than this size.
-static int maxUntiledSize = 510;
+static int maxUntiledSize = 512;
 
 // When tiling is enabled, use tiles of this dimension squared.
 static int defaultTileSize = 256;
 
 using namespace std;
 
 namespace WebCore {
 
 TiledLayerChromium::TiledLayerChromium(GraphicsLayerChromium* owner)
     : LayerChromium(owner)
     , m_tilingOption(AutoTile)
-    , m_borderTexels(true)
 {
 }
 
 TiledLayerChromium::~TiledLayerChromium()
 {
 }
 
 PassRefPtr<CCLayerImpl> TiledLayerChromium::createCCLayerImpl()
 {
     return CCTiledLayerImpl::create(this, id());
 }
 
 void TiledLayerChromium::cleanupResources()
 {
     m_tiler.clear();
     LayerChromium::cleanupResources();
 }
 
 void TiledLayerChromium::setLayerRenderer(LayerRendererChromium* layerRenderer)
 {
     LayerChromium::setLayerRenderer(layerRenderer);
     createTilerIfNeeded();
 }
 
 void TiledLayerChromium::updateTileSizeAndTilingOption()
 {
     if (!m_tiler)
         return;
 
-    const IntSize tileSize(defaultTileSize, defaultTileSize);
+    const IntSize tileSize(min(defaultTileSize, contentBounds().width()), min(defaultTileSize, contentBounds().height()));
 
     // Tile if both dimensions large, or any one dimension large and the other
     // extends into a second tile. This heuristic allows for long skinny layers
     // (e.g. scrollbars) that are Nx1 tiles to minimize wasted texture space.
     const bool anyDimensionLarge = contentBounds().width() > maxUntiledSize || contentBounds().height() > maxUntiledSize;
     const bool anyDimensionOneTile = contentBounds().width() <= defaultTileSize || contentBounds().height() <= defaultTileSize;
     const bool autoTiled = anyDimensionLarge && !anyDimensionOneTile;
 
     bool isTiled;
     if (m_tilingOption == AlwaysTile)
         isTiled = true;
     else if (m_tilingOption == NeverTile)
         isTiled = false;
     else
         isTiled = autoTiled;
 
-    // Empty tile size tells the tiler to avoid tiling.
-    IntSize requestedSize = isTiled ? tileSize : IntSize();
+    IntSize requestedSize = isTiled ? tileSize : contentBounds();
     const int maxSize = layerRenderer()->maxTextureSize();
     IntSize clampedSize = requestedSize.shrunkTo(IntSize(maxSize, maxSize));
     m_tiler->setTileSize(clampedSize);
 }
 
 bool TiledLayerChromium::drawsContent() const
 {
     if (!m_owner)
         return false;
 
     if (!m_tiler)
         return true;
 
     if (m_tilingOption == NeverTile && m_tiler->numTiles() > 1)
         return false;
 
     return !m_tiler->skipsDraw();
 }
 
 void TiledLayerChromium::createTilerIfNeeded()
 {
     if (m_tiler)
         return;
 
     createTextureUpdaterIfNeeded();
 
     m_tiler = LayerTilerChromium::create(
         layerRenderer(),
         IntSize(defaultTileSize, defaultTileSize),
-        m_borderTexels ? LayerTilerChromium::HasBorderTexels : LayerTilerChromium::NoBorderTexels);
+        LayerTilerChromium::HasBorderTexels);
 }
 
 void TiledLayerChromium::updateCompositorResources()
 {
     m_tiler->updateRect(textureUpdater());
 }
 
 void TiledLayerChromium::setTilingOption(TilingOption tilingOption)
 {
     m_tilingOption = tilingOption;
     updateTileSizeAndTilingOption();
 }
 
 void TiledLayerChromium::setIsMask(bool isMask)
 {
-    m_borderTexels = !isMask;
     setTilingOption(isMask ? NeverTile : AutoTile);
 }
 
 TransformationMatrix TiledLayerChromium::tilingTransform() const
 {
     TransformationMatrix transform = ccLayerImpl()->drawTransform();
 
     if (contentBounds().isEmpty())
         return transform;
 
@@ skipping 23 matching lines @@
 
 void TiledLayerChromium::dumpLayerProperties(TextStream& ts, int indent) const
 {
     LayerChromium::dumpLayerProperties(ts, indent);
     writeIndent(ts, indent);
     ts << "skipsDraw: " << (!m_tiler || m_tiler->skipsDraw()) << "\n";
 }
 
 }
 #endif // USE(ACCELERATED_COMPOSITING)