bump GrGpu reset context timestamp size

git-svn-id: http://skia.googlecode.com/svn/trunk@2606 2bbb7eff-a529-9590-31e7-b0007b416f81

src/gpu/GrGpu.cpp

@@ -32,7 +32,7 @@ extern void gr_run_unittests();
 
 GrGpu::GrGpu()
     : fContext(NULL)
-    , fResetCnt(0)
+    , fResetTimestamp(0)
     , fVertexPool(NULL)
     , fIndexPool(NULL)
     , fVertexPoolUseCnt(0)
@@ -62,11 +62,6 @@ GrGpu::~GrGpu() {
     this->releaseResources();
 }
 
-void GrGpu::resetContext() {
-    this->onResetContext();
-    ++fResetCnt;
-}
-
 void GrGpu::abandonResources() {
 
     while (NULL != fResourceHead) {

src/gpu/GrGpu.h

@@ -288,15 +288,20 @@ protected:
     void finalizeReservedVertices();
     void finalizeReservedIndices();
 
-    // called to handle re-emitting 3D API preample and dirtying state cache.
-    void resetContext();
-    // returns the number of times resetContext has been called. This value
-    // can be used a timestamp to detect when state cache is dirty.
-    int resetCount() const { return fResetCnt; }
+    // at 10 resets / frame and 60fps a 64bit timestamp will overflow in about
+    // a billion years.
+    typedef uint64_t ResetContextTimestamp;
     
-    // subclass implementation of resetContext
+    // called when the 3D context state is unknown. Subclass should emit any
+    // assumed 3D context state and dirty any state cache
     virtual void onResetContext() = 0;
 
+    // returns the number of times the context was reset. This timestamp can be
+    // used to lazily detect when cached 3D context state is dirty.
+    ResetContextTimestamp resetContextTimestamp() const {
+        return fResetTimestamp;
+    }
+    
     // overridden by API-specific derived class to create objects.
     virtual GrTexture* onCreateTexture(const GrTextureDesc& desc,
                                        const void* srcData,
@@ -369,7 +374,7 @@ protected:
 private:
     GrContext*                  fContext; // not reffed (context refs gpu)
     
-    int                         fResetCnt;
+    ResetContextTimestamp       fResetTimestamp;
 
     GrVertexBufferAllocPool*    fVertexPool;
 
@@ -419,6 +424,11 @@ private:
     // determines the path renderer used to draw a clip path element.
     GrPathRenderer* getClipPathRenderer(const SkPath& path, GrPathFill fill);
 
+    void resetContext() {
+        this->onResetContext();
+        ++fResetTimestamp;
+    }
+
     void handleDirtyContext() {
         if (fContextIsDirty) {
             this->resetContext();