SkTCopyOnFirstWrite-based SkPaintFilterCanvas API

src/utils/SkPaintFilterCanvas.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkPaintFilterCanvas.h"
 
 #include "SkPaint.h"
 #include "SkTLazy.h"
 
 class SkPaintFilterCanvas::AutoPaintFilter {
 public:
     AutoPaintFilter(const SkPaintFilterCanvas* canvas, Type type, const SkPaint* paint)
-        : fOrigPaint(paint) {
-        fShouldDraw = canvas->onFilter(fOrigPaint, type, &fFilteredPaint);
+        : fPaint(paint) {
+        fShouldDraw = canvas->onFilter(&fPaint, type);
     }
 
     AutoPaintFilter(const SkPaintFilterCanvas* canvas, Type type, const SkPaint& paint)
         : AutoPaintFilter(canvas, type, &paint) { }
 
-    const SkPaint* paint() const {
-        return fFilteredPaint.isValid() ? fFilteredPaint.get() : fOrigPaint;
-    }
+    const SkPaint* paint() const { return fPaint; }
 
     bool shouldDraw() const { return fShouldDraw; }
 
 private:
-    const SkPaint*   fOrigPaint;
-    SkTLazy<SkPaint> fFilteredPaint;
-    bool             fShouldDraw;
+    SkTCopyOnFirstWrite<SkPaint> fPaint;
+    bool                         fShouldDraw;
 };
 
 SkPaintFilterCanvas::SkPaintFilterCanvas(int width, int height) : INHERITED(width, height) { }
 
 SkPaintFilterCanvas::SkPaintFilterCanvas(SkCanvas *canvas)
     : INHERITED(canvas->imageInfo().width(), canvas->imageInfo().height()) {
 
     // Transfer matrix & clip state before adding the target canvas.
     SkIRect devClip;
     canvas->getClipDeviceBounds(&devClip);
@@ skipping 164 matching lines @@
     }
 }
 
 void SkPaintFilterCanvas::onDrawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y,
                                          const SkPaint& paint) {
     AutoPaintFilter apf(this, kTextBlob_Type, paint);
     if (apf.shouldDraw()) {
         this->INHERITED::onDrawTextBlob(blob, x, y, *apf.paint());
     }
 }