Pass accurate contentsScale to LayerImpl.

cc/layer_impl.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 
 #include "cc/layer_impl.h"
 
 #include "base/debug/trace_event.h"
 #include "base/stringprintf.h"
@@ skipping 11 matching lines @@
 namespace cc {
 
 LayerImpl::LayerImpl(int id)
     : m_parent(0)
     , m_maskLayerId(-1)
     , m_replicaLayerId(-1)
     , m_layerId(id)
     , m_layerTreeHostImpl(0)
     , m_anchorPoint(0.5, 0.5)
     , m_anchorPointZ(0)
+    , m_contentsScaleX(1.0)
+    , m_contentsScaleY(1.0)
     , m_scrollable(false)
     , m_shouldScrollOnMainThread(false)
     , m_haveWheelEventHandlers(false)
     , m_backgroundColor(0)
     , m_doubleSided(true)
     , m_layerPropertyChanged(false)
     , m_layerSurfacePropertyChanged(false)
     , m_masksToBounds(false)
     , m_contentsOpaque(false)
     , m_opacity(1.0)
@@ skipping 184 matching lines @@
     }
 
     return InputHandlerClient::ScrollStarted;
 }
 
 bool LayerImpl::drawCheckerboardForMissingTiles() const
 {
     return m_drawCheckerboardForMissingTiles && !Settings::backgroundColorInsteadOfCheckerboard();
 }
 
-IntRect LayerImpl::layerRectToContentRect(const WebKit::WebRect& layerRect)
+IntRect LayerImpl::layerRectToContentRect(const FloatRect& layerRect) const
 {
-    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);
-    return enclosingIntRect(contentRect);
+    FloatRect contentRect(layerRect);
+    contentRect.scale(contentsScaleX(), contentsScaleY());
+    IntRect intContentRect = enclosingIntRect(contentRect);
+    // Intersect with content rect to avoid the extra pixel because for some
+    // values x and y, ceil((x / y) * y) may be x + 1.
+    intContentRect.intersect(IntRect(IntPoint(), contentBounds()));
+    return intContentRect;
 }
 
 std::string LayerImpl::indentString(int indent)
 {
     std::string str;
     for (int i = 0; i != indent; ++i)
         str.append("  ");
     return str;
 }
 
@@ skipping 349 matching lines @@
 
 void LayerImpl::setContentBounds(const IntSize& contentBounds)
 {
     if (m_contentBounds == contentBounds)
         return;
 
     m_contentBounds = contentBounds;
     m_layerPropertyChanged = true;
 }
 
+void LayerImpl::setContentsScale(float contentsScaleX, float contentsScaleY)
+{
+    if (m_contentsScaleX == contentsScaleX && m_contentsScaleY == contentsScaleY)
+        return;
+
+    m_contentsScaleX = contentsScaleX;
+    m_contentsScaleY = contentsScaleY;
+    m_layerPropertyChanged = true;
+}
+
 void LayerImpl::setScrollPosition(const IntPoint& scrollPosition)
 {
     if (m_scrollPosition == scrollPosition)
         return;
 
     m_scrollPosition = scrollPosition;
     noteLayerPropertyChangedForSubtree();
 }
 
 void LayerImpl::setScrollDelta(const FloatSize& scrollDelta)
@@ skipping 63 matching lines @@
 
 void LayerImpl::setVerticalScrollbarLayer(ScrollbarLayerImpl* scrollbarLayer)
 {
     if (!m_scrollbarAnimationController)
         m_scrollbarAnimationController = ScrollbarAnimationController::create(this);
     m_scrollbarAnimationController->setVerticalScrollbarLayer(scrollbarLayer);
     m_scrollbarAnimationController->updateScrollOffset(this);
 }
 
 }