store map ptr in GrGeometryBuffer base class

src/gpu/GrGeometryBuffer.h

Index: src/gpu/GrGeometryBuffer.h
diff --git a/src/gpu/GrGeometryBuffer.h b/src/gpu/GrGeometryBuffer.h
index 1e1a367260216d01fe94f74c783aabd7d6c60716..67e91cc4d90a45a239159904edbb84360fb965cf 100644
--- a/src/gpu/GrGeometryBuffer.h
+++ b/src/gpu/GrGeometryBuffer.h
@@ -45,42 +45,58 @@ public:
      * Currently only one map at a time is supported (no nesting of
      * map/unmap).
      *
+     * Note that buffer mapping does not go through GrContext and therefore is
+     * not serialized with other operations.
+     *
      * @return a pointer to the data or NULL if the map fails.
      */
-    virtual void* map() = 0;
+     void* map() { return (fMapPtr = this->onMap()); }
 
     /**
-     * Returns the same ptr that map() returned at time of map or NULL if the
-     * is not mapped.
+     * Unmaps the buffer.
      *
-     * @return ptr to mapped buffer data or undefined if buffer is not mapped.
+     * The pointer returned by the previous map call will no longer be valid.
      */
-    virtual void* mapPtr() const = 0;
+     void unmap() {
+         SkASSERT(NULL != fMapPtr);
+         this->onUnmap();
+         fMapPtr = NULL;
+     }
 
     /**
-     * Unmaps the buffer.
+     * Returns the same ptr that map() returned at time of map or NULL if the
+     * is not mapped.
      *
-     * The pointer returned by the previous map call will no longer be valid.
+     * @return ptr to mapped buffer data or NULL if buffer is not mapped.
      */
-    virtual void unmap() = 0;
+     void* mapPtr() const { return fMapPtr; }
 
     /**
      Queries whether the buffer has been mapped.
 
      @return true if the buffer is mapped, false otherwise.
      */
-    virtual bool isMapped() const = 0;
+     bool isMapped() const { return NULL != fMapPtr; }
 
     /**
      * Updates the buffer data.
      *
      * The size of the buffer will be preserved. The src data will be
      * placed at the beginning of the buffer and any remaining contents will
-     * be undefined.
+     * be undefined. srcSizeInBytes must be <= to the buffer size.
+     *
+     * The buffer must not be mapped.
+     *
+     * Note that buffer updates do not go through GrContext and therefore are
+     * not serialized with other operations.
      *
      * @return returns true if the update succeeds, false otherwise.
      */
-    virtual bool updateData(const void* src, size_t srcSizeInBytes) = 0;
+    bool updateData(const void* src, size_t srcSizeInBytes) {
+        SkASSERT(!this->isMapped());
+        SkASSERT(srcSizeInBytes <= fGpuMemorySize);
+        return this->onUpdateData(src, srcSizeInBytes);
+    }
 
     // GrGpuObject overrides
     virtual size_t gpuMemorySize() const { return fGpuMemorySize; }
@@ -88,11 +104,17 @@ public:
 protected:
     GrGeometryBuffer(GrGpu* gpu, bool isWrapped, size_t gpuMemorySize, bool dynamic, bool cpuBacked)
         : INHERITED(gpu, isWrapped)
+        , fMapPtr(NULL)
         , fGpuMemorySize(gpuMemorySize)
         , fDynamic(dynamic)
         , fCPUBacked(cpuBacked) {}
 
 private:
+    virtual void* onMap() = 0;
+    virtual void onUnmap() = 0;
+    virtual bool onUpdateData(const void* src, size_t srcSizeInBytes) = 0;
+
+    void*    fMapPtr;
     size_t   fGpuMemorySize;
     bool     fDynamic;
     bool     fCPUBacked;