Pass accurate contentsScale to LayerImpl.

cc/layer.cc

Index: cc/layer.cc
diff --git a/cc/layer.cc b/cc/layer.cc
index 4c3912608c2448bb932ce16349d403e67dc7fc49..a079ed7699c44a10481e4345efa0b9d404ba1e1b 100644
--- a/cc/layer.cc
+++ b/cc/layer.cc
@@ -64,7 +64,6 @@ Layer::Layer()
     , m_renderTarget(0)
     , m_drawTransformIsAnimating(false)
     , m_screenSpaceTransformIsAnimating(false)
-    , m_contentsScale(1.0)
     , m_rasterScale(1.0)
     , m_automaticallyComputeRasterScale(false)
     , m_boundsContainPageScale(false)
@@ -122,10 +121,8 @@ void Layer::setNeedsCommit()
 
 IntRect Layer::layerRectToContentRect(const WebKit::WebRect& layerRect)
 {
-    float widthScale = static_cast<float>(contentBounds().width()) / bounds().width();
-    float heightScale = static_cast<float>(contentBounds().height()) / bounds().height();
     FloatRect contentRect(layerRect.x, layerRect.y, layerRect.width, layerRect.height);
-    contentRect.scale(widthScale, heightScale);
+    contentRect.scale(contentsScaleX(), contentsScaleY());
     return enclosingIntRect(contentRect);

[danakj, 2012/10/29 20:06:51]

Since this conversion is not exactly right for images always, we might end up
with a rect 1 pixel outside the area of the image. Can you intersect the result
with the area of the content bounds (ie Rect(Point(), contentBounds())) before
returning? Along with a comment explaining why.

[wangxianzhu, 2012/10/30 02:14:21]

Done.

 }
 
@@ -556,7 +553,7 @@ void Layer::pushPropertiesTo(LayerImpl* layer)
     layer->setAnchorPointZ(m_anchorPointZ);
     layer->setBackgroundColor(m_backgroundColor);
     layer->setBounds(m_bounds);
-    layer->setContentBounds(contentBounds());
+    layer->setContentsScale(contentsScaleX(), contentsScaleY());
     layer->setDebugBorderColor(m_debugBorderColor);
     layer->setDebugBorderWidth(m_debugBorderWidth);
     layer->setDebugName(m_debugName);
@@ -630,11 +627,6 @@ bool Layer::needMoreUpdates()
     return false;
 }
 
-bool Layer::needsContentsScale() const
-{
-    return false;
-}
-
 void Layer::setDebugBorderColor(SkColor color)
 {
     m_debugBorderColor = color;
@@ -653,15 +645,6 @@ void Layer::setDebugName(const std::string& debugName)
     setNeedsCommit();
 }
 
-void Layer::setContentsScale(float contentsScale)
-{
-    if (!needsContentsScale() || m_contentsScale == contentsScale)
-        return;
-    m_contentsScale = contentsScale;
-
-    setNeedsDisplay();
-}
-
 void Layer::setRasterScale(float scale)
 {
     if (m_rasterScale == scale)