Add a SkPixelSerializer SkImage encode variant

src/image/SkImage.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkData.h"
 #include "SkImageGenerator.h"
 #include "SkImagePriv.h"
 #include "SkImage_Base.h"
 #include "SkNextID.h"
 #include "SkPixelRef.h"
+#include "SkPixelSerializer.h"
 #include "SkReadPixelsRec.h"
 #include "SkString.h"
 #include "SkSurface.h"
 
 #if SK_SUPPORT_GPU
 #include "GrTexture.h"
 #include "GrContext.h"
 #include "SkImage_Gpu.h"
 #endif
 
@@ skipping 38 matching lines @@
 }
 
 SkData* SkImage::encode(SkImageEncoder::Type type, int quality) const {
     SkBitmap bm;
     if (as_IB(this)->getROPixels(&bm)) {
         return SkImageEncoder::EncodeData(bm, type, quality);
     }
     return nullptr;
 }
 
+namespace {
+
+class DefaultSerializer :  public SkPixelSerializer {
+protected:
+    bool onUseEncodedData(const void *data, size_t len) override {
+        return true;
+    }
+
+    SkData* onEncodePixels(const SkImageInfo& info, const void* pixels, size_t rowBytes) override {
+        return SkImageEncoder::EncodeData(info, pixels, rowBytes, SkImageEncoder::kPNG_Type, 100);
+    }
+};
+
+} // anonymous namespace
+
+SkData* SkImage::encode(SkPixelSerializer* serializer) const {
+    DefaultSerializer defaultSerializer;
+    SkPixelSerializer* effectiveSerializer = serializer ? serializer : &defaultSerializer;
+
+    SkAutoTUnref<SkData> encoded(this->refEncoded());
+    if (encoded && effectiveSerializer->useEncodedData(encoded->data(), encoded->size())) {
+        return encoded.detach();
+    }
+
+    SkBitmap bm;
+    SkAutoPixmapUnlock apu;
+    if (as_IB(this)->getROPixels(&bm) && bm.requestLock(&apu)) {
+        const SkPixmap& pmap = apu.pixmap();
+        return effectiveSerializer->encodePixels(pmap.info(), pmap.addr(), pmap.rowBytes());
+    }
+
+    return nullptr;
+}
+
 SkData* SkImage::refEncoded() const {
     return as_IB(this)->onRefEncoded();
 }
 
 SkImage* SkImage::NewFromEncoded(SkData* encoded, const SkIRect* subset) {
     if (nullptr == encoded || 0 == encoded->size()) {
         return nullptr;
     }
     SkImageGenerator* generator = SkImageGenerator::NewFromEncoded(encoded);
     return generator ? SkImage::NewFromGenerator(generator, subset) : nullptr;
@@ skipping 222 matching lines @@
 
 SkImage* SkImage::NewFromAdoptedTexture(GrContext*, const GrBackendTextureDesc&, SkAlphaType) {
     return nullptr;
 }
 
 SkImage* SkImage::NewFromTextureCopy(GrContext*, const GrBackendTextureDesc&, SkAlphaType) {
     return nullptr;
 }
 
 #endif