SkImage_Codec is Lazy

src/image/SkImage_Codec.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 "SkImageDecoder.h"
-#include "SkImage_Base.h"
-#include "SkBitmap.h"
-#include "SkCanvas.h"
-#include "SkData.h"
-
-class SkImage_Codec : public SkImage_Base {
-public:
-    static SkImage* NewEmpty();
-
-    SkImage_Codec(SkData* encodedData, int width, int height);
-    virtual ~SkImage_Codec();
-
-    virtual void onDraw(SkCanvas*, SkScalar, SkScalar, const SkPaint*) const SK_OVERRIDE;
-    virtual void onDrawRectToRect(SkCanvas*, const SkRect*, const SkRect&,
-                                  const SkPaint*) const SK_OVERRIDE;
-
-private:
-    SkData*     fEncodedData;
-    SkBitmap    fBitmap;
-
-    typedef SkImage_Base INHERITED;
-};
-
-///////////////////////////////////////////////////////////////////////////////
-
-SkImage_Codec::SkImage_Codec(SkData* data, int width, int height) : INHERITED(width, height) {
-    fEncodedData = data;
-    fEncodedData->ref();
-}
-
-SkImage_Codec::~SkImage_Codec() {
-    fEncodedData->unref();
-}
-
-void SkImage_Codec::onDraw(SkCanvas* canvas, SkScalar x, SkScalar y, const SkPaint* paint) const {
-    if (!fBitmap.pixelRef()) {
-        // todo: this needs to be thread-safe
-        SkBitmap* bitmap = const_cast<SkBitmap*>(&fBitmap);
-        if (!SkImageDecoder::DecodeMemory(fEncodedData->bytes(), fEncodedData->size(), bitmap)) {
-            return;
-        }
-    }
-    canvas->drawBitmap(fBitmap, x, y, paint);
-}
-
-void SkImage_Codec::onDrawRectToRect(SkCanvas* canvas, const SkRect* src, const SkRect& dst,
-                                     const SkPaint* paint) const {
-    if (!fBitmap.pixelRef()) {
-        // todo: this needs to be thread-safe
-        SkBitmap* bitmap = const_cast<SkBitmap*>(&fBitmap);
-        if (!SkImageDecoder::DecodeMemory(fEncodedData->bytes(), fEncodedData->size(), bitmap)) {
-            return;
-        }
-    }
-    canvas->drawBitmapRectToRect(fBitmap, src, dst, paint);
-}
-
-///////////////////////////////////////////////////////////////////////////////
-
-SkImage* SkImage::NewEncodedData(SkData* data) {
-    if (NULL == data) {
-        return NULL;
-    }
-
-    SkBitmap bitmap;
-    if (!SkImageDecoder::DecodeMemory(data->bytes(), data->size(), &bitmap, kUnknown_SkColorType,
-                                      SkImageDecoder::kDecodeBounds_Mode)) {
-        return NULL;
-    }
-
-    return SkNEW_ARGS(SkImage_Codec, (data, bitmap.width(), bitmap.height()));
-}