Reland of 8525 with fix for case when GrRT outlives GrTexture.
Review URL: https://codereview.chromium.org/13814015
git-svn-id: http://skia.googlecode.com/svn/trunk@8573 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/gpu/GrSurface.h b/include/gpu/GrSurface.h
index 02fc0d5..52a5665 100644
--- a/include/gpu/GrSurface.h
+++ b/include/gpu/GrSurface.h
@@ -64,6 +64,22 @@
virtual const GrRenderTarget* asRenderTarget() const = 0;
/**
+ * Checks whether this GrSurface refers to the same GPU object as other. This
+ * catches the case where a GrTexture and GrRenderTarget refer to the same
+ * GPU memory.
+ */
+ bool isSameAs(const GrSurface* other) const {
+ const GrRenderTarget* thisRT = this->asRenderTarget();
+ if (NULL != thisRT) {
+ return thisRT == other->asRenderTarget();
+ } else {
+ const GrTexture* thisTex = this->asTexture();
+ GrAssert(NULL != thisTex); // We must be one or the other
+ return thisTex == other->asTexture();
+ }
+ }
+
+ /**
* Reads a rectangle of pixels from the surface.
* @param left left edge of the rectangle to read (inclusive)
* @param top top edge of the rectangle to read (inclusive)