Add layer counting to SkPictureRecord

src/core/SkPictureContentInfo.h

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPictureContentInfo_DEFINED
 #define SkPictureContentInfo_DEFINED
 
 class GrContext;
 
 class SkPictureContentInfo {
 public:
     SkPictureContentInfo() { this->reset(); }
     SkPictureContentInfo(const SkPictureContentInfo& src) { this->set(src); }
 
     int numOperations() const { return fNumOperations; }
     bool hasText() const { return fNumTexts > 0; }
     bool suitableForGpuRasterization(GrContext* context, const char **reason,
                                      int sampleCount) const;
+    bool suitableForOptimization() const { return fNumLayers > 0; }
 
     void addOperation() { ++fNumOperations; }
 
     void onDrawPoints(size_t count, const SkPaint& paint);
     void onDrawPath(const SkPath& path, const SkPaint& paint);
     void onAddPaintPtr(const SkPaint* paint);
     void onDrawText() { ++fNumTexts; }
 
+    void onSaveLayer();
+    void onSave();
+    void onRestore();
+    void rescindLastSave();
+    void rescindLastSaveLayer();
+
     void set(const SkPictureContentInfo& src);
     void reset();
     void swap(SkPictureContentInfo* other);
 
 private:
     // Raw count of operations in the picture
     int fNumOperations;
     // Count of all forms of drawText
     int fNumTexts;
 
     // This field is incremented every time a paint with a path effect is
     // used (i.e., it is not a de-duplicated count)
     int fNumPaintWithPathEffectUses;
     // This field is incremented every time a paint with a path effect that is
     // dashed, we are drawing a line, and we can use the gpu fast path
     int fNumFastPathDashEffects;
     // This field is incremented every time an anti-aliased drawPath call is
     // issued with a concave path
     int fNumAAConcavePaths;
     // This field is incremented every time a drawPath call is
     // issued for a hairline stroked concave path.
     int fNumAAHairlineConcavePaths;
+    // These fields track the different layer flavors. fNumLayers is just
+    // a count of all saveLayers, fNumInteriorLayers is the number of layers
+    // with a layer inside them, fNumLeafLayers is the number of layers with
+    // no layer inside them.
+    int fNumLayers;
+    int fNumInteriorLayers;
+    int fNumLeafLayers;
+
+    enum Flags {
+        kSave_Flag      = 0x1,
+        kSaveLayer_Flag = 0x2,
+
+        // Did the current save or saveLayer contain another saveLayer.
+        // Percolated back down the save stack.
+        kContainedSaveLayer_Flag = 0x4
+    };
+
+    // Stack of save vs saveLayer information to track nesting
+    SkTDArray<uint32_t> fSaveStack;
 };
 
 #endif