BitmapTextBatch and BitmapTextBlob

src/gpu/GrBatchAtlas.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrBatchAtlas_DEFINED
 #define GrBatchAtlas_DEFINED
 
 #include "GrTexture.h"
 #include "SkPoint.h"
 #include "SkTDArray.h"
 #include "SkTInternalLList.h"
 
 class BatchPlot;
 class GrBatchTarget;
 class GrRectanizer;
 
 typedef SkTInternalLList<BatchPlot> GrBatchPlotList;
 
 class GrBatchAtlas {
 public:
     typedef uint64_t BatchToken;
     // An AtlasID is an opaque handle which callers can use to determine if the atlas contains
     // a specific piece of data
     typedef uint32_t AtlasID;
+    static const uint32_t kInvalidAtlasID = 0;
+    static const uint64_t kInvalidAtlasGeneration = 0;
 
     // A function pointer for use as a callback during eviction.  Whenever GrBatchAtlas evicts a
     // specific AtlasID, it will call all of the registered listeners so they can optionally process
     // the eviction
     typedef void (*EvictionFunc)(GrBatchAtlas::AtlasID, void*);
 
     GrBatchAtlas(GrTexture*, int numPlotsX, int numPlotsY);
     ~GrBatchAtlas();
 
     // Adds a width x height subimage to the atlas. Upon success it returns
     // the containing GrPlot and absolute location in the backing texture.
     // NULL is returned if the subimage cannot fit in the atlas.
     // If provided, the image data will be written to the CPU-side backing bitmap.
     bool addToAtlas(AtlasID*, GrBatchTarget*, int width, int height, const void* image,
                     SkIPoint16* loc);
 
     GrTexture* getTexture() const { return fTexture; }
 
+    uint64_t atlasGeneration() const { return fAtlasGeneration; }
     bool hasID(AtlasID id);
     void setLastRefToken(AtlasID id, BatchToken batchToken);
     void registerEvictionCallback(EvictionFunc func, void* userData) {
         EvictionData* data = fEvictionCallbacks.append();
         data->fFunc = func;
         data->fData = userData;
     }
 
 private:
     int getIndexFromID(AtlasID id) {
         return id & 0xffff;
     }
 
     int getGenerationFromID(AtlasID id) {
         return (id >> 16) & 0xffff;
     }
 
     inline void updatePlot(GrBatchTarget*, AtlasID*, BatchPlot*);
 
     inline void makeMRU(BatchPlot* plot);
 
     inline void processEviction(AtlasID);
 
     GrTexture* fTexture;
     int fNumPlotsX;
     int fNumPlotsY;
     int fPlotWidth;
     int fPlotHeight;
     size_t fBPP;
+    uint64_t fAtlasGeneration;
 
     struct EvictionData {
         EvictionFunc fFunc;
         void* fData;
     };
 
     SkTDArray<EvictionData> fEvictionCallbacks;
     // allocated array of GrBatchPlots
     SkAutoTUnref<BatchPlot>* fPlotArray;
     // LRU list of GrPlots (MRU at head - LRU at tail)
     GrBatchPlotList fPlotList;
 };
 
 #endif