Add read/write-Pixels to GrDrawContext

src/gpu/GrDrawContext.cpp

Index: src/gpu/GrDrawContext.cpp
diff --git a/src/gpu/GrDrawContext.cpp b/src/gpu/GrDrawContext.cpp
index 2bb9caa8b170d994862b5e0e51965fe9159023b2..e76683033cbb5fd2e9cbf6fe802cbca7864687c0 100644
--- a/src/gpu/GrDrawContext.cpp
+++ b/src/gpu/GrDrawContext.cpp
@@ -37,6 +37,7 @@
 
 #include "../private/GrAuditTrail.h"
 
+#include "SkGr.h"
 #include "SkLatticeIter.h"
 #include "SkMatrixPriv.h"
 
@@ -1125,6 +1126,39 @@ void GrDrawContext::drawNonAAFilledRect(const GrClip& clip,
     this->getDrawTarget()->drawBatch(pipelineBuilder, this, clip, batch);
 }
 
+bool GrDrawContext::readPixels(const SkImageInfo& dstInfo, void* dstBuffer, size_t dstRowBytes,
+                               int x, int y) {
+    // TODO: teach fRenderTarget to take ImageInfo directly to specify the src pixels
+    GrPixelConfig config = SkImageInfo2GrPixelConfig(dstInfo, *fContext->caps());
+    if (kUnknown_GrPixelConfig == config) {
+        return false;
+    }
+
+    uint32_t flags = 0;
+    if (kUnpremul_SkAlphaType == dstInfo.alphaType()) {
+        flags = GrContext::kUnpremul_PixelOpsFlag;
+    }
+
+    return fRenderTarget->readPixels(x, y, dstInfo.width(), dstInfo.height(),
+                                     config, dstBuffer, dstRowBytes, flags);
+}
+
+bool GrDrawContext::writePixels(const SkImageInfo& srcInfo, const void* srcBuffer,
+                                size_t srcRowBytes, int x, int y) {
+    // TODO: teach fRenderTarget to take ImageInfo directly to specify the src pixels
+    GrPixelConfig config = SkImageInfo2GrPixelConfig(srcInfo, *fContext->caps());
+    if (kUnknown_GrPixelConfig == config) {
+        return false;
+    }
+    uint32_t flags = 0;
+    if (kUnpremul_SkAlphaType == srcInfo.alphaType()) {
+        flags = GrContext::kUnpremul_PixelOpsFlag;
+    }
+
+    return fRenderTarget->writePixels(x, y, srcInfo.width(), srcInfo.height(),
+                                      config, srcBuffer, srcRowBytes, flags);
+}
+
 // Can 'path' be drawn as a pair of filled nested rectangles?
 static bool fills_as_nested_rects(const SkMatrix& viewMatrix, const SkPath& path, SkRect rects[2]) {