[SVG] Shared <use> path geometry

third_party/WebKit/Source/core/svg/SVGPath.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * 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
  * version 2 of the License, or (at your option) any later version.
@@ skipping 14 matching lines @@
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "core/SVGNames.h"
 #include "core/svg/SVGAnimationElement.h"
 #include "core/svg/SVGPathBlender.h"
 #include "core/svg/SVGPathByteStream.h"
 #include "core/svg/SVGPathByteStreamBuilder.h"
 #include "core/svg/SVGPathByteStreamSource.h"
 #include "core/svg/SVGPathParser.h"
 #include "core/svg/SVGPathUtilities.h"
+#include "platform/graphics/Path.h"
 
 namespace blink {
 
 SVGPath::SVGPath()
     : SVGPropertyBase(classType())
 {
 }
 
 SVGPath::SVGPath(PassOwnPtr<SVGPathByteStream> byteStream)
     : SVGPropertyBase(classType())
     , m_byteStream(byteStream)
 {
 }
 
 SVGPath::~SVGPath()
 {
 }
 
+const Path& SVGPath::path() const
+{
+    if (!m_cachedPath) {
+        m_cachedPath = adoptPtr(new Path);
+        buildPathFromByteStream(byteStream(), *m_cachedPath);
+    }
+
+    return *m_cachedPath;
+}
+
 PassRefPtrWillBeRawPtr<SVGPath> SVGPath::clone() const
 {
     return adoptRefWillBeNoop(new SVGPath(byteStream().copy()));
 }
 
 PassRefPtrWillBeRawPtr<SVGPropertyBase> SVGPath::cloneForAnimation(const String& value) const
 {
     RefPtrWillBeRawPtr<SVGPath> svgPath = SVGPath::create();
     svgPath->setValueAsString(value, IGNORE_EXCEPTION);
     return svgPath;
 }
 
+SVGPathByteStream& SVGPath::ensureByteStream()
+{
+    if (!m_byteStream)
+        m_byteStream = SVGPathByteStream::create();
+
+    return *m_byteStream.get();
+}
+
+void SVGPath::byteStreamWillChange()
+{
+    m_cachedPath.clear();
+}
+
 const SVGPathByteStream& SVGPath::byteStream() const
 {
-    return const_cast<SVGPath*>(this)->mutableByteStream();
+    return const_cast<SVGPath*>(this)->ensureByteStream();
 }
 
 SVGPathByteStream& SVGPath::mutableByteStream()
 {
-    if (!m_byteStream)
-        m_byteStream = SVGPathByteStream::create();
-    return *m_byteStream.get();
+    byteStreamWillChange();
+    return ensureByteStream();
 }
 
 String SVGPath::valueAsString() const
 {
     String string;
     buildStringFromByteStream(byteStream(), string, UnalteredParsing);
     return string;
 }
 
 void SVGPath::setValueAsString(const String& string, ExceptionState& exceptionState)
@@ skipping 26 matching lines @@
 
     // If no 'to' value is given, nothing to animate.
     if (!toStream.size())
         return;
 
     if (isToAnimation) {
         copy = byteStream().copy();
         fromStream = copy.get();
     }
 
+    byteStreamWillChange();
+
     // If the 'from' value is given and it's length doesn't match the 'to' value list length, fallback to a discrete animation.
     if (fromStream->size() != toStream.size() && fromStream->size()) {
         if (percentage < 0.5) {
             if (!isToAnimation) {
                 m_byteStream = fromStream->copy();
                 return;
             }
         } else {
             m_byteStream = toStream.copy();
             return;
@@ skipping 20 matching lines @@
         addToSVGPathByteStream(*m_byteStream, toAtEndOfDuration->byteStream(), repeatCount);
 }
 
 float SVGPath::calculateDistance(PassRefPtrWillBeRawPtr<SVGPropertyBase> to, SVGElement*)
 {
     // FIXME: Support paced animations.
     return -1;
 }
 
 }