Implementation for cc::Picture::IsCheapInRect().

skia/ext/analysis_canvas.h

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef SKIA_EXT_ANALYSIS_CANVAS_H_
+#define SKIA_EXT_ANALYSIS_CANVAS_H_
+
+#include "third_party/skia/include/core/SkCanvas.h"
+#include "third_party/skia/include/core/SkDevice.h"
+
+namespace skia {
+
+class AnalysisDevice;
+
+// Does not render anything, but gathers statistics about a region
+// (specified as a clip rectangle) of an SkPicture as the picture is
+// played back through it.
+// To use: create a SkBitmap with kNo_Config, create an AnalysisDevice
+// using that bitmap, and create an AnalysisCanvas using the device.
+// Play a picture into the canvas, and then check isCheap().
+class SK_API AnalysisCanvas : public SkCanvas {
+ public:
+  AnalysisCanvas(AnalysisDevice*);
+  virtual ~AnalysisCanvas();
+
+  // Returns true if the estimated cost of drawing is below an
+  // arbitrary threshold.
+  bool isCheap() const;
+
+  // Returns the estimated cost of drawing, in arbitrary units.
+  int getEstimatedCost() const;
+
+  virtual bool clipRect(const SkRect& rect,
+                        SkRegion::Op op = SkRegion::kIntersect_Op,
+                        bool doAntiAlias = false) OVERRIDE;
+  virtual bool clipPath(const SkPath& path,
+                        SkRegion::Op op = SkRegion::kIntersect_Op,
+                        bool doAntiAlias = false) OVERRIDE;
+  virtual bool clipRRect(const SkRRect& rrect,
+                         SkRegion::Op op = SkRegion::kIntersect_Op,
+                         bool doAntiAlias = false) OVERRIDE;
+
+  virtual int saveLayer(const SkRect* bounds, const SkPaint*,
+                              SkCanvas::SaveFlags flags) OVERRIDE;
+ private:
+  typedef SkCanvas INHERITED;
+};
+
+class SK_API AnalysisDevice : public SkDevice {
+ public:
+  AnalysisDevice(const SkBitmap& bm);
+  virtual ~AnalysisDevice();
+
+  int getEstimatedCost() const;
+
+ protected:
+  virtual void clear(SkColor color) OVERRIDE;
+  virtual void drawPaint(const SkDraw&, const SkPaint& paint) OVERRIDE;
+  virtual void drawPoints(const SkDraw&, SkCanvas::PointMode mode,
+                          size_t count, const SkPoint[],
+                          const SkPaint& paint) OVERRIDE;
+  virtual void drawRect(const SkDraw&, const SkRect& r,
+                        const SkPaint& paint) OVERRIDE;
+  virtual void drawOval(const SkDraw&, const SkRect& oval,
+                        const SkPaint& paint) OVERRIDE;
+  virtual void drawPath(const SkDraw&, const SkPath& path,
+                        const SkPaint& paint,
+                        const SkMatrix* prePathMatrix = NULL,
+                        bool pathIsMutable = false) OVERRIDE;
+  virtual void drawBitmap(const SkDraw&, const SkBitmap& bitmap,
+                          const SkIRect* srcRectOrNull,
+                          const SkMatrix& matrix, const SkPaint& paint)
+                          OVERRIDE;
+  virtual void drawSprite(const SkDraw&, const SkBitmap& bitmap,
+                          int x, int y, const SkPaint& paint) OVERRIDE;
+  virtual void drawBitmapRect(const SkDraw&, const SkBitmap&,
+                              const SkRect* srcOrNull, const SkRect& dst,
+                              const SkPaint& paint) OVERRIDE;
+  virtual void drawText(const SkDraw&, const void* text, size_t len,
+                        SkScalar x, SkScalar y, const SkPaint& paint)
+                        OVERRIDE;
+  virtual void drawPosText(const SkDraw& draw, const void* text, size_t len,
+                           const SkScalar pos[], SkScalar constY,
+                           int scalarsPerPos, const SkPaint& paint) OVERRIDE;
+  virtual void drawTextOnPath(const SkDraw&, const void* text, size_t len,
+                              const SkPath& path, const SkMatrix* matrix,
+                              const SkPaint& paint) OVERRIDE;
+#ifdef SK_BUILD_FOR_ANDROID
+  virtual void drawPosTextOnPath(const SkDraw& draw, const void* text,
+                                 size_t len,
+                                 const SkPoint pos[], const SkPaint& paint,
+                                 const SkPath& path, const SkMatrix* matrix)
+                                 OVERRIDE;
+#endif
+  virtual void drawVertices(const SkDraw&, SkCanvas::VertexMode,
+                            int vertexCount,
+                            const SkPoint verts[], const SkPoint texs[],
+                            const SkColor colors[], SkXfermode* xmode,
+                            const uint16_t indices[], int indexCount,
+                            const SkPaint& paint) OVERRIDE;
+  virtual void drawDevice(const SkDraw&, SkDevice*, int x, int y,
+                          const SkPaint&) OVERRIDE;
+
+  int estimatedCost_;
+
+ private:
+  typedef SkDevice INHERITED;
+};
+
+}  // namespace skia
+
+#endif  // SKIA_EXT_ANALYSIS_CANVAS_H_
+