add SkImage from encoded data

git-svn-id: http://skia.googlecode.com/svn/trunk/src@4845 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 67 insertions, 0 deletions

diff --git a/image/SkImage_Codec.cpp b/image/SkImage_Codec.cpp
new file mode 100644
index 00000000..af7e0db0
--- /dev/null
+++ b/image/SkImage_Codec.cpp
@@ -0,0 +1,67 @@
+/*
+ * 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 "SkImage_Base.h"
+#include "SkBitmap.h"
+#include "SkCanvas.h"
+#include "SkData.h"
+#include "../images/SkImageDecoder.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*) 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) {
+    if (!fBitmap.pixelRef()) {
+        if (!SkImageDecoder::DecodeMemory(fEncodedData->bytes(), fEncodedData->size(),
+                                          &fBitmap)) {
+            return;
+        }
+    }
+    canvas->drawBitmap(fBitmap, x, y, paint);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+SkImage* SkImage::NewEncodedData(SkData* data) {
+    if (NULL == data) {
+        return NULL;
+    }
+
+    SkBitmap bitmap;
+    if (!SkImageDecoder::DecodeMemory(data->bytes(), data->size(), &bitmap,
+                                      SkBitmap::kNo_Config,
+                                      SkImageDecoder::kDecodeBounds_Mode)) {
+        return NULL;
+    }
+    
+    return SkNEW_ARGS(SkImage_Codec, (data, bitmap.width(), bitmap.height()));
+}
+