skia2/include/gpu/GrSurface.h

133 lines
4.5 KiB
C++

/*
* 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; }
/**
* Some surfaces will be stored such that the upper and left edges of the content meet at the
* the origin (in texture coord space) and for other surfaces the lower and left edges meet at
* the origin. Render-targets are always consistent with the convention of the underlying
* backend API to make it easier to mix native backend rendering with Skia rendering. Wrapped
* backend surfaces always use the backend's convention as well.
*/
enum Origin {
kTopLeft_Origin,
kBottomLeft_Origin,
};
Origin origin() const {
GrAssert(kTopLeft_Origin == fOrigin || kBottomLeft_Origin == fOrigin);
return fOrigin;
}
/**
* 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 between consecutive rows. Zero means rows are tightly
* packed.
* @param pixelOpsFlags See the GrContext::PixelOpsFlags enum.
*
* @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,
uint32_t pixelOpsFlags = 0) = 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 between consecutive rows. Zero means rows are tightly
* packed.
* @param pixelOpsFlags See the GrContext::PixelOpsFlags enum.
*/
virtual void writePixels(int left, int top, int width, int height,
GrPixelConfig config,
const void* buffer,
size_t rowBytes = 0,
uint32_t pixelOpsFlags = 0) = 0;
protected:
GrSurface(GrGpu* gpu, const GrTextureDesc& desc, Origin origin)
: INHERITED(gpu)
, fDesc(desc)
, fOrigin(origin) {
}
GrTextureDesc fDesc;
private:
Origin fOrigin;
typedef GrResource INHERITED;
};
#endif // GrSurface_DEFINED