WIP RasterCanvasLayerAllocator experiment 2

src/core/SkRasterCanvasLayerAllocator.cpp

Index: src/core/SkRasterCanvasLayerAllocator.cpp
diff --git a/src/core/SkRasterCanvasLayerAllocator.cpp b/src/core/SkRasterCanvasLayerAllocator.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..9807adbb692ef153628f4ebd654e9a9a902a2e83
--- /dev/null
+++ b/src/core/SkRasterCanvasLayerAllocator.cpp
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkRasterCanvasLayerAllocator.h"
+
+#include "SkBitmapDevice.h"
+
+SkRasterCanvasLayerAllocator::SkRasterCanvasLayerAllocator() { }
+
+SkRasterCanvasLayerAllocator::~SkRasterCanvasLayerAllocator() { }
+
+SkCanvas* SkRasterCanvasLayerAllocator::CreateCanvas(const SkImageInfo& info,
+                                                     const SkSurfaceProps& props,
+                                                     void* initialData) {
+    SkAutoTUnref<SkBaseDevice> newDevice;
+    SkBitmap bitmap;
+    size_t rowBytes;
+    void* pixels = this->allocateLayer(info, &rowBytes, initialData);
+    if (!pixels) {
+        return nullptr;
+    }
+    bitmap.installPixels(info, pixels, rowBytes);
+    SkBitmapDevice* device = new SkBitmapDevice(bitmap, props);

[reed1, 2016/09/16 13:15:00]

why do we allocate a device here?

+    return new SkCanvas(bitmap, this);
+}
+
+