Prefer unprefixed clip-path to (webkit) prefixed

Source/core/rendering/svg/SVGRenderingContext.cpp

 /*
  * Copyright (C) 2007, 2008 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Google, Inc.  All rights reserved.
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) Research In Motion Limited 2009-2010. 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
@@ skipping 68 matching lines @@
     ASSERT(object);
 
 #if ENABLE(ASSERT)
     // This function must not be called twice!
     ASSERT(!(m_renderingFlags & PrepareToRenderSVGContentWasCalled));
     m_renderingFlags |= PrepareToRenderSVGContentWasCalled;
 #endif
 
     m_object = object;
     m_paintInfo = &paintInfo;
-    m_filter = 0;
 
     RenderStyle* style = m_object->style();
     ASSERT(style);
 
     const SVGRenderStyle& svgStyle = style->svgStyle();
 
     // Setup transparency layers before setting up SVG resources!
     bool isRenderingMask = SVGRenderSupport::isRenderingClipPathAsMaskImage(*m_object);
     // RenderLayer takes care of root opacity.
-    float opacity = (object->isSVGRoot() || isRenderingMask) ? 1 : style->opacity();
-    bool hasBlendMode = style->hasBlendMode() && !isRenderingMask;
+    float opacity = object->isSVGRoot() ? 1 : style->opacity();
+    bool hasBlendMode = style->hasBlendMode();
 
-    if (opacity < 1 || hasBlendMode || style->hasIsolation()) {
+    if (!isRenderingMask && (opacity < 1 || hasBlendMode || style->hasIsolation())) {

[f(malita), 2014/10/31 17:24:46]

This shuffling has side effects: hasIsolation() no longer forces a layer when
isRenderingMask == true. Is this intentional?

[fs, 2014/10/31 19:29:22]

I made (maybe too brief?) note about this in the last paragraph of the
description. Since a clipPath is "geometry only", 'isolation' will (should) have
no effect. (Since it helps define grouping for blending.)

[f(malita), 2014/10/31 19:36:35]

Thanks, I missed that. LGTM.

         FloatRect paintInvalidationRect = m_object->paintInvalidationRectInLocalCoordinates();
         m_paintInfo->context->clip(paintInvalidationRect);
 
         if (hasBlendMode) {
             if (!(m_renderingFlags & RestoreGraphicsContext)) {
                 m_paintInfo->context->save();
                 m_renderingFlags |= RestoreGraphicsContext;
             }
             m_paintInfo->context->setCompositeOperation(CompositeSourceOver, style->blendMode());
         }
 
         m_paintInfo->context->beginTransparencyLayer(opacity);
 
         if (hasBlendMode)
             m_paintInfo->context->setCompositeOperation(CompositeSourceOver, WebBlendModeNormal);
 
         m_renderingFlags |= EndOpacityLayer;
     }
 
-    ClipPathOperation* clipPathOperation = style->clipPath();
-    if (clipPathOperation && clipPathOperation->type() == ClipPathOperation::SHAPE) {
-        ShapeClipPathOperation* clipPath = toShapeClipPathOperation(clipPathOperation);
-        m_paintInfo->context->clipPath(clipPath->path(object->objectBoundingBox()), clipPath->windRule());
+    SVGResources* resources = SVGResourcesCache::cachedResourcesForRenderObject(m_object);
+
+    // Prefer a 'clipper' (non-prefixed 'clip-path') to a 'clip shape'
+    // ('-webkit-clip-path'), until these two properties end up being merged
+    // properly.
+    if (RenderSVGResourceClipper* clipper = resources ? resources->clipper() : nullptr) {
+        if (!clipper->applyStatefulResource(m_object, m_paintInfo->context, m_clipperState))
+            return;
+        m_clipper = clipper;
+        m_renderingFlags |= PostApplyResources;
+    } else {
+        ClipPathOperation* clipPathOperation = style->clipPath();
+        if (clipPathOperation && clipPathOperation->type() == ClipPathOperation::SHAPE) {
+            ShapeClipPathOperation* clipPath = toShapeClipPathOperation(clipPathOperation);
+            m_paintInfo->context->clipPath(clipPath->path(object->objectBoundingBox()), clipPath->windRule());
+        }
     }
 
-    SVGResources* resources = SVGResourcesCache::cachedResourcesForRenderObject(m_object);
-    if (!resources) {
-        if (svgStyle.hasFilter())
-            return;
-
+    if (isRenderingMask) {
         m_renderingFlags |= RenderingPrepared;
         return;
     }
 
-    if (!isRenderingMask) {
+    if (resources) {
         if (RenderSVGResourceMasker* masker = resources->masker()) {
             if (!masker->prepareEffect(m_object, m_paintInfo->context))
                 return;
             m_masker = masker;
             m_renderingFlags |= PostApplyResources;
         }
-    }
 
-    RenderSVGResourceClipper* clipper = resources->clipper();
-    if (!clipPathOperation && clipper) {
-        if (!clipper->applyStatefulResource(m_object, m_paintInfo->context, m_clipperState))
-            return;
-        m_clipper = clipper;
-        m_renderingFlags |= PostApplyResources;
-    }
-
-    if (!isRenderingMask) {
         m_filter = resources->filter();
         if (m_filter) {
             m_savedContext = m_paintInfo->context;
             m_savedPaintRect = m_paintInfo->rect;
             // Return with false here may mean that we don't need to draw the content
             // (because it was either drawn before or empty) but we still need to apply the filter.
             m_renderingFlags |= PostApplyResources;
             if (!m_filter->prepareEffect(m_object, m_paintInfo->context))
                 return;
 
             // Since we're caching the resulting bitmap and do not invalidate it on paint invalidation rect
             // changes, we need to paint the whole filter region. Otherwise, elements not visible
             // at the time of the initial paint (due to scrolling, window size, etc.) will never
             // be drawn.
             m_paintInfo->rect = IntRect(m_filter->drawingRegion(m_object));
         }
+    } else {
+        // Broken filter disables rendering.
+        if (svgStyle.hasFilter())
+            return;
     }
 
     m_renderingFlags |= RenderingPrepared;
 }
 
 static AffineTransform& currentContentTransformation()
 {
     DEFINE_STATIC_LOCAL(AffineTransform, s_currentContentTransformation, ());
     return s_currentContentTransformation;
 }
@@ skipping 56 matching lines @@
 {
     ASSERT(context);
     ASSERT(item);
     ASSERT(!item->needsLayout());
 
     PaintInfo info(context, PaintInfo::infiniteRect(), PaintPhaseForeground, PaintBehaviorNormal);
     item->paint(info, IntPoint());
 }
 
 } // namespace blink