Raise the loading priority of in-viewport images.

Source/core/rendering/RenderBlock.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 14 matching lines @@
 #include "core/rendering/RenderBlock.h"
 
 #include "HTMLNames.h"
 #include "core/accessibility/AXObjectCache.h"
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
 #include "core/events/OverflowEvent.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/editing/Editor.h"
 #include "core/editing/FrameSelection.h"
+#include "core/fetch/ResourceLoadPriorityOptimizer.h"
 #include "core/frame/Frame.h"
 #include "core/frame/FrameView.h"
 #include "core/page/Page.h"
 #include "core/page/Settings.h"
 #include "core/platform/graphics/GraphicsContextStateSaver.h"
 #include "core/rendering/FastTextAutosizer.h"
 #include "core/rendering/GraphicsContextAnnotator.h"
 #include "core/rendering/HitTestLocation.h"
 #include "core/rendering/HitTestResult.h"
 #include "core/rendering/InlineIterator.h"
 #include "core/rendering/InlineTextBox.h"
 #include "core/rendering/LayoutRectRecorder.h"
 #include "core/rendering/LayoutRepainter.h"
 #include "core/rendering/PaintInfo.h"
 #include "core/rendering/RenderCombineText.h"
 #include "core/rendering/RenderDeprecatedFlexibleBox.h"
 #include "core/rendering/RenderFlexibleBox.h"
 #include "core/rendering/RenderInline.h"
 #include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderMarquee.h"
 #include "core/rendering/RenderNamedFlowThread.h"
 #include "core/rendering/RenderRegion.h"
 #include "core/rendering/RenderTableCell.h"
 #include "core/rendering/RenderTextFragment.h"
 #include "core/rendering/RenderTheme.h"
 #include "core/rendering/RenderView.h"
 #include "core/rendering/shapes/ShapeOutsideInfo.h"
+#include "core/rendering/style/ContentData.h"
+#include "core/rendering/style/RenderStyle.h"
 #include "platform/geometry/FloatQuad.h"
 #include "platform/geometry/TransformState.h"
 #include "wtf/StdLibExtras.h"
 #include "wtf/TemporaryChange.h"
 
 using namespace std;
 using namespace WTF;
 using namespace Unicode;
 
 namespace WebCore {
@@ skipping 1180 matching lines @@
         return;
 
     // It's safe to check for control clip here, since controls can never be table cells.
     // If we have a lightweight clip, there can never be any overflow from children.
     if (hasControlClip() && m_overflow)
         clearLayoutOverflow();
 
     invalidateBackgroundObscurationStatus();
 }
 
+void RenderBlock::didLayout(ResourceLoadPriorityOptimizer& optimizer)
+{
+    RenderBox::didLayout(optimizer);
+    updateStyleImageLoadingPriorities(optimizer);
+}
+
+void RenderBlock::didScroll(ResourceLoadPriorityOptimizer& optimizer)
+{
+    RenderBox::didScroll(optimizer);
+    updateStyleImageLoadingPriorities(optimizer);
+}
+
+void RenderBlock::updateStyleImageLoadingPriorities(ResourceLoadPriorityOptimizer& optimizer)
+{
+    RenderStyle* blockStyle = style();
+    if (!blockStyle)
+        return;
+
+    LayoutRect objectBounds = absoluteContentBox();
+    LayoutRect viewBounds = viewRect();
+
+    // The object bounds might be empty right now, so intersects will fail since it doesn't deal
+    // with empty rects. Use LayoutRect::contains in that case.
+    bool isVisible;
+    if (!objectBounds.isEmpty())
+        isVisible =  viewBounds.intersects(objectBounds);
+    else
+        isVisible = viewBounds.contains(objectBounds);
+
+    ResourceLoadPriorityOptimizer::VisibilityStatus status = isVisible ?
+        ResourceLoadPriorityOptimizer::Visible : ResourceLoadPriorityOptimizer::NotVisible;
+
+    for (FillLayer* layer = blockStyle->accessBackgroundLayers(); layer; layer = layer->next()) {
+        if (layer->image()) {
+            ImageResource* img = layer->image()->cachedImage();
+            if (img) {
+                optimizer.notifyImageResourceVisibility(img, status);
+            }
+        }
+    }
+    for (FillLayer* layer = blockStyle->accessMaskLayers(); layer; layer = layer->next()) {
+        if (layer->image()) {
+            ImageResource* img = layer->image()->cachedImage();
+            if (img) {
+                optimizer.notifyImageResourceVisibility(img, status);
+            }
+        }
+    }
+    ContentData* contentData = const_cast<ContentData*>(blockStyle->contentData());
+    if (contentData && contentData->isImage()) {
+        ImageContentData* imageContentData = static_cast<ImageContentData*>(contentData);
+        if (imageContentData->image() && imageContentData->image()->cachedImage())
+            optimizer.notifyImageResourceVisibility(imageContentData->image()->cachedImage(), status);
+    }
+    if (blockStyle->boxReflect()) {
+        if (blockStyle->boxReflect()->mask().image()) {
+            if (blockStyle->boxReflect()->mask().image()->cachedImage()) {
+                optimizer.notifyImageResourceVisibility(blockStyle->boxReflect()->mask().image()->cachedImage(), status);
+            }
+        }
+    }
+    if (blockStyle->listStyleImage() && blockStyle->listStyleImage()->cachedImage())
+        optimizer.notifyImageResourceVisibility(blockStyle->listStyleImage()->cachedImage(), status);
+    if (blockStyle->borderImageSource() && blockStyle->borderImageSource()->cachedImage())
+        optimizer.notifyImageResourceVisibility(blockStyle->borderImageSource()->cachedImage(), status);
+    if (blockStyle->maskBoxImageSource() && blockStyle->maskBoxImageSource()->cachedImage())
+        optimizer.notifyImageResourceVisibility(blockStyle->maskBoxImageSource()->cachedImage(), status);
+}
+
 void RenderBlock::relayoutShapeDescendantIfMoved(RenderBlock* child, LayoutSize offset)
 {
     LayoutUnit left = isHorizontalWritingMode() ? offset.width() : offset.height();
     if (!left || !child || child->shapeInsideInfo() || !layoutShapeInsideInfo())
         return;
     // Propagate layout markers only up to the child, as we are still in the middle
     // of a layout pass
     child->setNormalChildNeedsLayout(true);
     child->markShapeInsideDescendantsForLayout();
     child->layoutIfNeeded();
@@ skipping 4511 matching lines @@
 void RenderBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const RenderObject* obj) const
 {
     showRenderObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace WebCore