gecko-dev/gfx/gl/GLReadTexImageHelper.h

80 строки
2.6 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* vim: set ts=8 sts=4 et sw=4 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef GLREADTEXIMAGEHELPER_H_
#define GLREADTEXIMAGEHELPER_H_
#include "GLContextTypes.h"
#include "mozilla/Attributes.h"
#include "nsSize.h"
#include "nsAutoPtr.h"
#include "mozilla/RefPtr.h"
#include "mozilla/gfx/Types.h"
namespace mozilla {
namespace gfx {
class DataSourceSurface;
}
namespace gl {
// Returns true if the `dest{Format,Type}` are the same as the
// `read{Format,Type}`.
bool GetActualReadFormats(GLContext* gl,
GLenum destFormat, GLenum destType,
GLenum* out_readFormat, GLenum* out_readType);
void ReadPixelsIntoDataSurface(GLContext* aGL,
gfx::DataSourceSurface* aSurface);
TemporaryRef<gfx::DataSourceSurface>
ReadBackSurface(GLContext* gl, GLuint aTexture, bool aYInvert, gfx::SurfaceFormat aFormat);
class GLReadTexImageHelper final
{
// The GLContext is the sole owner of the GLBlitHelper.
GLContext* mGL;
GLuint mPrograms[4];
GLuint TextureImageProgramFor(GLenum aTextureTarget, int aShader);
bool DidGLErrorOccur(const char* str);
public:
explicit GLReadTexImageHelper(GLContext* gl);
~GLReadTexImageHelper();
/**
* Read the image data contained in aTexture, and return it as an ImageSurface.
* If GL_RGBA is given as the format, a gfxImageFormat::ARGB32 surface is returned.
* Not implemented yet:
* If GL_RGB is given as the format, a gfxImageFormat::RGB24 surface is returned.
* If GL_LUMINANCE is given as the format, a gfxImageFormat::A8 surface is returned.
*
* THIS IS EXPENSIVE. It is ridiculously expensive. Only do this
* if you absolutely positively must, and never in any performance
* critical path.
*
* NOTE: aShaderProgram is really mozilla::layers::ShaderProgramType. It is
* passed as int to eliminate including LayerManagerOGLProgram.h here.
*/
TemporaryRef<gfx::DataSourceSurface> ReadTexImage(GLuint aTextureId,
GLenum aTextureTarget,
const gfx::IntSize& aSize,
/* ShaderProgramType */ int aShaderProgram,
bool aYInvert = false);
};
}
}
#endif