Raise the loading priority of in-viewport images.

Source/core/rendering/RenderImage.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011-2012. All rights reserved.
  *
@@ skipping 13 matching lines @@
  * Boston, MA 02110-1301, USA.
  *
  */
 
 #include "config.h"
 #include "core/rendering/RenderImage.h"
 
 #include "HTMLNames.h"
 #include "core/editing/FrameSelection.h"
 #include "core/fetch/ImageResource.h"
+#include "core/fetch/ResourceLoadPriorityOptimizer.h"
+#include "core/fetch/ResourceLoader.h"
 #include "core/html/HTMLAreaElement.h"
 #include "core/html/HTMLImageElement.h"
 #include "core/html/HTMLInputElement.h"
 #include "core/html/HTMLMapElement.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/frame/Frame.h"
 #include "core/platform/graphics/Font.h"
 #include "core/platform/graphics/FontCache.h"
 #include "core/platform/graphics/GraphicsContext.h"
 #include "core/platform/graphics/GraphicsContextStateSaver.h"
@@ skipping 522 matching lines @@
         m_altText = toHTMLImageElement(node())->altText();
 }
 
 void RenderImage::layout()
 {
     LayoutRectRecorder recorder(*this);
     RenderReplaced::layout();
     updateInnerContentRect();
 }
 
+void RenderImage::didLayout(ResourceLoadPriorityOptimizer& optimizer)
+{
+    RenderReplaced::didLayout(optimizer);
+    updateImageLoadingPriority(optimizer);
+}
+
+void RenderImage::didScroll(ResourceLoadPriorityOptimizer& optimizer)
+{
+    RenderReplaced::didScroll(optimizer);
+    updateImageLoadingPriority(optimizer);
+}
+
+void RenderImage::updateImageLoadingPriority(ResourceLoadPriorityOptimizer& optimizer)
+{
+    if (m_imageResource->cachedImage() && !m_imageResource->cachedImage()->isLoaded()) {

[eseidel, 2013/11/27 20:58:35]

nit: Early returns are preferred over long if blocks.

[shatch, 2013/12/02 22:32:46]

Done. Also changed that in RenderBlock.

+        LayoutRect objectBounds = absoluteContentBox();
+        LayoutRect viewBounds = viewRect();
+
+        ResourceLoadPriorityOptimizer::VisibilityStatus status = viewBounds.intersects(objectBounds) ?
+            ResourceLoadPriorityOptimizer::Visible : ResourceLoadPriorityOptimizer::NotVisible;
+        optimizer.notifyImageResourceVisibility(m_imageResource->cachedImage(), status);
+    }
+}
+
 void RenderImage::computeIntrinsicRatioInformation(FloatSize& intrinsicSize, double& intrinsicRatio, bool& isPercentageIntrinsicSize) const
 {
     RenderReplaced::computeIntrinsicRatioInformation(intrinsicSize, intrinsicRatio, isPercentageIntrinsicSize);
 
     // Our intrinsicSize is empty if we're rendering generated images with relative width/height. Figure out the right intrinsic size to use.
     if (intrinsicSize.isEmpty() && (m_imageResource->imageHasRelativeWidth() || m_imageResource->imageHasRelativeHeight())) {
         RenderObject* containingBlock = isOutOfFlowPositioned() ? container() : this->containingBlock();
         if (containingBlock->isBox()) {
             RenderBox* box = toRenderBox(containingBlock);
             intrinsicSize.setWidth(box->availableLogicalWidth());
@@ skipping 20 matching lines @@
         return 0;
 
     ImageResource* cachedImage = m_imageResource->cachedImage();
     if (cachedImage && cachedImage->image() && cachedImage->image()->isSVGImage())
         return toSVGImage(cachedImage->image())->embeddedContentBox();
 
     return 0;
 }
 
 } // namespace WebCore