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src/image/SkImage.cpp

Index: src/image/SkImage.cpp
diff --git a/src/image/SkImage.cpp b/src/image/SkImage.cpp
index 5521b6e305fddf0cc54663f82df30ff712c12aab..453ecb08ee150ed0956cd554df87b56429d03d31 100644
--- a/src/image/SkImage.cpp
+++ b/src/image/SkImage.cpp
@@ -89,6 +89,55 @@ void SkImage::preroll(GrContext* ctx) const {
     }
 }
 
+SkImageTextureData* SkImage::newImageTextureData(
+        const GrContextThreadSafeProxy& proxy,
+        const std::function<void*(size_t, const SkImage*)>& allocate) const {
+    SkPixmap pixmap;
+    if (!this->peekPixels(&pixmap)) {
+        return nullptr;
+    }
+    size_t size = 0;
+    size_t itdSize = SkAlign8(sizeof(SkImageTextureData));
+    size += itdSize;
+    size_t pixelOffset = size;
+    size_t pixelSize = SkAlign8(pixmap.getSafeSize());
+    size += pixelSize;
+    size_t ctOffset = size;
+    int ctCount = 0;
+    size_t ctSize = 0;
+    if (pixmap.ctable()) {
+        ctCount = pixmap.ctable()->count();
+        ctSize = SkAlign8(pixmap.ctable()->count() * 4);
+        size += ctSize;
+    }
+    intptr_t allocation = reinterpret_cast<intptr_t>(allocate(size, this));
+    void* itd = reinterpret_cast<void*>(allocation);
+    void* pixels = reinterpret_cast<void*>(allocation + pixelOffset);
+    SkPMColor* ct = nullptr;
+    if (ctSize) {
+        ct = reinterpret_cast<SkPMColor*>(allocation + ctOffset);
+    }
+
+    memcpy(pixels, pixmap.addr(), pixmap.getSafeSize());
+    if (ctSize) {
+        memcpy(ct, pixmap.ctable()->readColors(), ctSize);
+    }
+
+    const SkImageInfo& info = pixmap.info();
+    size_t rowBytes = pixmap.rowBytes();
+    SkImageTextureData* textureData = new (itd) SkImageTextureData();
+    textureData->fContextUniqueID = proxy.fContextUniqueID;
+    textureData->fImageUniqueID = this->uniqueID();
+    textureData->fPixmapGenerator = [info, pixels, rowBytes, ct, ctCount] (SkPixmap* pixmap) {
+        SkAutoTUnref<SkColorTable> colorTable;
+        if (ct) {
+            colorTable.reset(new SkColorTable(ct, ctCount));
+        }
+        pixmap->reset(info, pixels, rowBytes, colorTable.get());
+    };
+    return textureData;
+}
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 SkShader* SkImage::newShader(SkShader::TileMode tileX,