new API for retrieving YUV data

include/core/SkPixelRef.h

Index: include/core/SkPixelRef.h
diff --git a/include/core/SkPixelRef.h b/include/core/SkPixelRef.h
index 109d3c911e94160569b9bda4fae9ac5cd6ecf313..079422386b6072d0fdc048a2b30ef92841e046e6 100644
--- a/include/core/SkPixelRef.h
+++ b/include/core/SkPixelRef.h
@@ -232,6 +232,7 @@ public:
      */
     virtual GrTexture* getTexture() { return NULL; }
 
+#ifdef SK_SUPPORT_LEGACY_IMAGEGENERATOR_YUV_API
     /**
      *  If any planes or rowBytes is NULL, this should output the sizes and return true
      *  if it can efficiently return YUV planar data. If it cannot, it should return false.
@@ -247,6 +248,40 @@ public:
                        SkYUVColorSpace* colorSpace) {
         return this->onGetYUV8Planes(sizes, planes, rowBytes, colorSpace);
     }
+#endif
+
+    /**
+     *  If this pixelref supports returning planar YUV data, return true, and return
+     *  the logicalSizes (if not NULL) and the optimalAllocationSizes (if not NULL), where each
+     *  array represents [0]=Y, [1]=U, [2]=V
+     *
+     *  The optimalAllocationSizes may be the same as the logicalSizes, but they may also be larger
+     *  if that will aid the pixelref (for performance).
+     *
+     *  If this returns false, the value of the (optional) sizes parameters is undefined.
+     */
+    bool queryYUV8(SkISize logicalSizes[3], SkISize optimalAllocationSizes[3]) {
+        return this->onQueryYUV8(logicalSizes, optimalAllocationSizes);
+    }
+
+    /**
+     *  If this pixelref supports returning planar YUV data, and can fulfill the requested
+     *  sizes for each plane, return true and write the YUV data into the planes.
+     *
+     *  Calling queryYUV8() will return both the logical sizes (W/H) and the optimal-allocation
+     *  sizes for the 3 planes. For getYUV8(), tt is legal to pass the logical sizes
+     *  (though smaller than those will return false). However, this may
+     *  (depending on the implementation) be slower than passing in the optimal-allocation sizes
+     *  (or larger). The extra space may allow the implementation to run faster at the cost of
+     *  slightly more ram being allocated. There should be no performance penalty for the
+     *  allocationSizes to larger than the values in optimalAllocationSizes, as they are just the
+     *  minimum sizes for best performance.
+     *
+     *  If colorSpace is not NULL, return the corresponding colorSpace for the YUV data.
+     */
+    bool getYUV8(const SkISize allocationSizes[3], void* planes[3], SkYUVColorSpace* colorSpace) {
+        return this->onGetYUV8(allocationSizes, planes, colorSpace);
+    }
 
     bool readPixels(SkBitmap* dst, const SkIRect* subset = NULL);
 
@@ -335,9 +370,20 @@ protected:
     // default impl returns NULL.
     virtual SkData* onRefEncodedData();
 
-    // default impl returns false.
+    virtual bool onQueryYUV8(SkISize logicalSizes[3], SkISize optimalAllocationSizes[3]) {
+        return false;
+    }
+
+    virtual bool onGetYUV8(const SkISize sizes[3], void* planes[3], SkYUVColorSpace*) {
+        return false;
+    }
+
+#ifdef SK_SUPPORT_LEGACY_IMAGEGENERATOR_YUV_API
     virtual bool onGetYUV8Planes(SkISize sizes[3], void* planes[3], size_t rowBytes[3],
-                                 SkYUVColorSpace* colorSpace);
+                                 SkYUVColorSpace* colorSpace) {
+        return false;
+    }
+#endif
 
     /**
      *  Returns the size (in bytes) of the internally allocated memory.