[SVG] Shared <use> path geometry

third_party/WebKit/Source/core/layout/svg/LayoutSVGShape.h

 /*
  * Copyright (C) 2004, 2005, 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005 Rob Buis <buis@kde.org>
  * Copyright (C) 2005 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2006 Apple Computer, Inc
  * Copyright (C) 2009 Google, Inc.
  * Copyright (C) 2011 Renata Hodovan <reni@webkit.org>
  * Copyright (C) 2011 University of Szeged
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 112 matching lines @@
     bool nodeAtFloatPoint(HitTestResult&, const FloatPoint& pointInParent, HitTestAction) final;
 
     FloatRect strokeBoundingBox() const final { return m_strokeBoundingBox; }
     FloatRect calculateObjectBoundingBox() const;
     FloatRect calculateStrokeBoundingBox() const;
     void updatePaintInvalidationBoundingBox();
     void updateLocalTransform();
 
 private:
     OwnPtr<AffineTransform> m_localTransform;
+    // TODO(fmalita): the Path is now cached in SVGPath; while this additional cache is just a

[fs, 2015/10/30 09:48:34]

When (if) we manage to turn 'd' into a property well essentially be carry a Path
in ComputedStyle, so hopefully that would fix some part of this. There's still
the cases of all the non-<path> geometries that we turn into Paths for various
reasons, so I guess we need to think some more about that...

+    // shallow copy, it certainly has a complexity/state management cost (plus allocation & storage
+    // overhead) - so we should look into removing it.
     OwnPtr<Path> m_path;
     mutable OwnPtr<LayoutSVGShapeRareData> m_rareData;
 
     bool m_needsBoundariesUpdate : 1;
     bool m_needsShapeUpdate : 1;
     bool m_needsTransformUpdate : 1;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutSVGShape, isSVGShape());
 
 }
 
 #endif