Refactor shadow rendering logic.

Source/core/rendering/RenderBoxModelObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. 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
@@ skipping 13 matching lines @@
  */
 
 #include "config.h"
 #include "core/rendering/RenderBoxModelObject.h"
 
 #include "HTMLNames.h"
 #include "core/html/HTMLFrameOwnerElement.h"
 #include "core/page/Page.h"
 #include "core/page/Settings.h"
 #include "core/page/scrolling/ScrollingConstraints.h"
+#include "core/platform/graphics/DrawLooper.h"
 #include "core/platform/graphics/GraphicsContextStateSaver.h"
 #include "core/platform/graphics/ImageBuffer.h"
 #include "core/platform/graphics/Path.h"
 #include "core/platform/graphics/transforms/TransformState.h"
 #include "core/rendering/ImageQualityController.h"
 #include "core/rendering/RenderBlock.h"
 #include "core/rendering/RenderInline.h"
 #include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderLayerBacking.h"
 #include "core/rendering/RenderLayerCompositor.h"
@@ skipping 469 matching lines @@
     return getBackgroundRoundedRect(borderRect, box, boxSize.width(), boxSize.height(), includeLogicalLeftEdge, includeLogicalRightEdge);
 }
 
 static void applyBoxShadowForBackground(GraphicsContext* context, RenderStyle* style)
 {
     const ShadowData* boxShadow = style->boxShadow();
     while (boxShadow->style() != Normal)
         boxShadow = boxShadow->next();
 
     FloatSize shadowOffset(boxShadow->x(), boxShadow->y());
-    context->setShadow(shadowOffset, boxShadow->blur(), boxShadow->color(), style->colorSpace());
+    context->setShadow(shadowOffset, boxShadow->blur(), boxShadow->color(), DrawLooper::ShadowIgnoresAlpha);
 }
 
 void RenderBoxModelObject::paintFillLayerExtended(const PaintInfo& paintInfo, const Color& color, const FillLayer* bgLayer, const LayoutRect& rect,
     BackgroundBleedAvoidance bleedAvoidance, InlineFlowBox* box, const LayoutSize& boxSize, CompositeOperator op, RenderObject* backgroundObject)
 {
     GraphicsContext* context = paintInfo.context;
     if (context->paintingDisabled() || rect.isEmpty())
         return;
 
     bool includeLeftEdge = box ? box->includeLogicalLeftEdge() : true;
@@ skipping 1851 matching lines @@
             shadowRect.move(shadowOffset);
 
             GraphicsContextStateSaver stateSaver(*context);
             context->clip(shadowRect);
 
             // Move the fill just outside the clip, adding 1 pixel separation so that the fill does not
             // bleed in (due to antialiasing) if the context is transformed.
             IntSize extraOffset(paintRect.pixelSnappedWidth() + max(0, shadowOffset.width()) + shadowBlur + 2 * shadowSpread + 1, 0);
             shadowOffset -= extraOffset;
             fillRect.move(extraOffset);
-            context->setShadow(shadowOffset, shadowBlur, shadowColor, s->colorSpace());
+            context->setShadow(shadowOffset, shadowBlur, shadowColor, DrawLooper::ShadowIgnoresAlpha);
 
             if (hasBorderRadius) {
                 RoundedRect rectToClipOut = border;
 
                 // If the box is opaque, it is unnecessary to clip it out. However, doing so saves time
                 // when painting the shadow. On the other hand, it introduces subpixel gaps along the
                 // corners. Those are avoided by insetting the clipping path by one pixel.
                 if (hasOpaqueBackground) {
                     rectToClipOut.inflateWithRadii(-1);
                 }
@@ skipping 69 matching lines @@
                 Path path;
                 path.addRoundedRect(border);
                 context->clip(path);
                 roundedHole.shrinkRadii(shadowSpread);
             } else
                 context->clip(border.rect());
 
             IntSize extraOffset(2 * paintRect.pixelSnappedWidth() + max(0, shadowOffset.width()) + shadowBlur - 2 * shadowSpread + 1, 0);
             context->translate(extraOffset.width(), extraOffset.height());
             shadowOffset -= extraOffset;
-            context->setShadow(shadowOffset, shadowBlur, shadowColor, s->colorSpace());
+            context->setShadow(shadowOffset, shadowBlur, shadowColor, DrawLooper::ShadowIgnoresAlpha);
             context->fillRectWithRoundedHole(outerRect, roundedHole, fillColor, s->colorSpace());
         }
     }
 }
 
 LayoutUnit RenderBoxModelObject::containingBlockLogicalWidthForContent() const
 {
     return containingBlock()->availableLogicalWidth();
 }
 
@@ skipping 165 matching lines @@
     ASSERT(!beforeChild || toBoxModelObject == beforeChild->parent());
     for (RenderObject* child = startChild; child && child != endChild; ) {
         // Save our next sibling as moveChildTo will clear it.
         RenderObject* nextSibling = child->nextSibling();
         moveChildTo(toBoxModelObject, child, beforeChild, fullRemoveInsert);
         child = nextSibling;
     }
 }
 
 } // namespace WebCore