Add GrSurface parent class above GrTexture & GrRenderTarget
http://codereview.appspot.com/6297092/
git-svn-id: http://skia.googlecode.com/svn/trunk@4292 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/gpu/GrSurface.h b/include/gpu/GrSurface.h
new file mode 100644
index 0000000..2d39b5e
--- /dev/null
+++ b/include/gpu/GrSurface.h
@@ -0,0 +1,107 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+
+#ifndef GrSurface_DEFINED
+#define GrSurface_DEFINED
+
+#include "GrTypes.h"
+#include "GrResource.h"
+
+class GrTexture;
+class GrRenderTarget;
+
+class GrSurface : public GrResource {
+public:
+ SK_DECLARE_INST_COUNT(GrSurface);
+
+ /**
+ * Retrieves the width of the surface.
+ *
+ * @return the width in texels
+ */
+ int width() const { return fDesc.fWidth; }
+
+ /**
+ * Retrieves the height of the surface.
+ *
+ * @return the height in texels
+ */
+ int height() const { return fDesc.fHeight; }
+
+ /**
+ * Retrieves the pixel config specified when the surface was created.
+ * For render targets this can be kUnknown_GrPixelConfig
+ * if client asked us to render to a target that has a pixel
+ * config that isn't equivalent with one of our configs.
+ */
+ GrPixelConfig config() const { return fDesc.fConfig; }
+
+ /**
+ * Return the descriptor describing the surface
+ */
+ const GrTextureDesc& desc() const { return fDesc; }
+
+ /**
+ * @return the texture associated with the surface, may be NULL.
+ */
+ virtual GrTexture* asTexture() = 0;
+ virtual const GrTexture* asTexture() const = 0;
+
+ /**
+ * @return the render target underlying this surface, may be NULL.
+ */
+ virtual GrRenderTarget* asRenderTarget() = 0;
+ virtual const GrRenderTarget* asRenderTarget() const = 0;
+
+ /**
+ * Reads a rectangle of pixels from the surface.
+ * @param left left edge of the rectangle to read (inclusive)
+ * @param top top edge of the rectangle to read (inclusive)
+ * @param width width of rectangle to read in pixels.
+ * @param height height of rectangle to read in pixels.
+ * @param config the pixel config of the destination buffer
+ * @param buffer memory to read the rectangle into.
+ * @param rowBytes number of bytes bewtween consecutive rows. Zero
+ * means rows are tightly packed.
+ *
+ * @return true if the read succeeded, false if not. The read can fail
+ * because of an unsupported pixel config.
+ */
+ virtual bool readPixels(int left, int top, int width, int height,
+ GrPixelConfig config, void* buffer,
+ size_t rowBytes) = 0;
+
+ /**
+ * Copy the src pixels [buffer, rowbytes, pixelconfig] into the surface
+ * at the specified rectangle.
+ * @param left left edge of the rectangle to write (inclusive)
+ * @param top top edge of the rectangle to write (inclusive)
+ * @param width width of rectangle to write in pixels.
+ * @param height height of rectangle to write in pixels.
+ * @param config the pixel config of the source buffer
+ * @param buffer memory to read the rectangle from.
+ * @param rowBytes number of bytes bewtween consecutive rows. Zero
+ * means rows are tightly packed.
+ */
+ virtual void writePixels(int left, int top, int width, int height,
+ GrPixelConfig config, const void* buffer,
+ size_t rowBytes) = 0;
+
+protected:
+ GrTextureDesc fDesc;
+
+ GrSurface(GrGpu* gpu, const GrTextureDesc& desc)
+ : INHERITED(gpu)
+ , fDesc(desc) {
+ }
+
+private:
+ typedef GrResource INHERITED;
+};
+
+#endif // GrSurface_DEFINED