[SVGDom] Add more presentation attributes.

experimental/svg/model/SkSVGRenderContext.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkSVGRenderContext_DEFINED
 #define SkSVGRenderContext_DEFINED
 
 #include "SkPaint.h"
 #include "SkRect.h"
 #include "SkSize.h"
+#include "SkSVGAttribute.h"
 #include "SkTLazy.h"
 #include "SkTypes.h"
 
 class SkCanvas;
 class SkSVGLength;
 
 class SkSVGLengthContext {
 public:
     SkSVGLengthContext(const SkSize& viewport) : fViewport(viewport) {}
 
     enum class LengthType {
         kHorizontal,
         kVertical,
         kOther,
     };
 
     const SkSize& viewPort() const { return fViewport; }
     void setViewPort(const SkSize& viewport) { fViewport = viewport; }
 
     SkScalar resolve(const SkSVGLength&, LengthType) const;
     SkRect   resolveRect(const SkSVGLength& x, const SkSVGLength& y,
                          const SkSVGLength& w, const SkSVGLength& h) const;
 
 private:
     SkSize fViewport;
 };
 
-class SkSVGPresentationContext {
-public:
+struct SkSVGPresentationContext {
     SkSVGPresentationContext();
-    SkSVGPresentationContext(const SkSVGPresentationContext&);
-    SkSVGPresentationContext& operator=(const SkSVGPresentationContext&);
+    SkSVGPresentationContext(const SkSVGPresentationContext&)            = default;
+    SkSVGPresentationContext& operator=(const SkSVGPresentationContext&) = default;
 
-    const SkPaint* fillPaint() const { return fFill.getMaybeNull(); }
-    const SkPaint* strokePaint() const { return fStroke.getMaybeNull(); }
+    // Inherited presentation attributes, computed for the current node.
+    SkSVGPresentationAttributes fInherited;
 
-    void setFillColor(SkColor);
-    void setStrokeColor(SkColor);
-
-private:
-    void initFrom(const SkSVGPresentationContext&);
-
-    SkPaint& ensureFill();
-    SkPaint& ensureStroke();
-
-    // TODO: convert to regular SkPaints and track explicit attribute values instead.
-    SkTLazy<SkPaint> fFill;
-    SkTLazy<SkPaint> fStroke;
+    // Cached paints, reflecting the current presentation attributes.
+    SkPaint fFillPaint;
+    SkPaint fStrokePaint;
 };
 
 class SkSVGRenderContext {
 public:
     SkSVGRenderContext(SkCanvas*, const SkSVGLengthContext&, const SkSVGPresentationContext&);
     SkSVGRenderContext(const SkSVGRenderContext&);
     ~SkSVGRenderContext();
 
     const SkSVGLengthContext& lengthContext() const { return *fLengthContext; }
     SkSVGLengthContext* writableLengthContext() { return fLengthContext.writable(); }
 
-    const SkSVGPresentationContext& presentationContext() const { return *fPresentationContext; }
-    SkSVGPresentationContext* writablePresentationContext() {
-        return fPresentationContext.writable();
-    }
+    SkCanvas* canvas() const { return fCanvas; }
 
-    SkCanvas* canvas() const { return fCanvas; }
+    void applyPresentationAttributes(const SkSVGPresentationAttributes&);
+
+    const SkPaint* fillPaint() const;
+    const SkPaint* strokePaint() const;
 
 private:
     // Stack-only
     void* operator new(size_t)                               = delete;
     void* operator new(size_t, void*)                        = delete;
     SkSVGRenderContext& operator=(const SkSVGRenderContext&) = delete;
 
     SkTCopyOnFirstWrite<SkSVGLengthContext>       fLengthContext;
     SkTCopyOnFirstWrite<SkSVGPresentationContext> fPresentationContext;
     SkCanvas*                                     fCanvas;
     // The save count on 'fCanvas' at construction time.
     // A restoreToCount() will be issued on destruction.
     int                                           fCanvasSaveCount;
 };
 
 #endif // SkSVGRenderContext_DEFINED