source: downloads/RenderSystems/GL/include/OgreGLHardwarePixelBuffer.h @ 3

/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2006 Torus Knot Software Ltd
Also see acknowledgements in Readme.html

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place - Suite 330, Boston, MA 02111-1307, USA, or go to
http://www.gnu.org/copyleft/lesser.txt.

You may alternatively use this source under the terms of a specific version of
the OGRE Unrestricted License provided you have obtained such a license from
Torus Knot Software Ltd.
-----------------------------------------------------------------------------
*/
#ifndef __GLPIXELBUFFER_H__
#define __GLPIXELBUFFER_H__

#include "OgreGLPrerequisites.h"
#include "OgreHardwarePixelBuffer.h"

namespace Ogre {
        class _OgrePrivate GLHardwarePixelBuffer: public HardwarePixelBuffer
        {
        protected:  
                /// Lock a box
                PixelBox lockImpl(const Image::Box lockBox,  LockOptions options);

                /// Unlock a box
                void unlockImpl(void);
        
                // Internal buffer; either on-card or in system memory, freed/allocated on demand
                // depending on buffer usage
                PixelBox mBuffer;
        GLenum mGLInternalFormat; // GL internal format
                LockOptions mCurrentLockOptions;
                
                // Buffer allocation/freeage
                void allocateBuffer();
                void freeBuffer();
                // Upload a box of pixels to this buffer on the card
                virtual void upload(const PixelBox &data);
                // Download a box of pixels from the card
                virtual void download(const PixelBox &data);
        public:
        /// Should be called by HardwareBufferManager
        GLHardwarePixelBuffer(size_t mWidth, size_t mHeight, size_t mDepth,
                PixelFormat mFormat,
                HardwareBuffer::Usage usage);
                
                /// @copydoc HardwarePixelBuffer::blitFromMemory
                void blitFromMemory(const PixelBox &src, const Image::Box &dstBox);
                
                /// @copydoc HardwarePixelBuffer::blitToMemory
                void blitToMemory(const Image::Box &srcBox, const PixelBox &dst);
                
                ~GLHardwarePixelBuffer();
        
        /** Bind surface to frame buffer. Needs FBO extension.
        */
        virtual void bindToFramebuffer(GLenum attachment, size_t zoffset);
        GLenum getGLFormat() { return mGLInternalFormat; }
        };

    /** Texture surface.
    */
    class _OgrePrivate GLTextureBuffer: public GLHardwarePixelBuffer
        {
    public:
        /** Texture constructor */
                GLTextureBuffer(const String &baseName, GLenum target, GLuint id, GLint face, GLint level, Usage usage, 
                        bool softwareMipmap);
        ~GLTextureBuffer();
        
        /// @copydoc GLHardwarePixelBuffer::bindToFramebuffer
        virtual void bindToFramebuffer(GLenum attachment, size_t zoffset);
        /// @copydoc ardwarePixelBuffer::getRenderTarget
        RenderTexture* getRenderTarget(size_t);
        // Upload a box of pixels to this buffer on the card
                virtual void upload(const PixelBox &data);
                // Download a box of pixels from the card
                virtual void download(const PixelBox &data);
  
        // Hardware implementation of blitFromMemory
        virtual void blitFromMemory(const PixelBox &src_orig, const Image::Box &dstBox);
        
        // Notify TextureBuffer of destruction of render target
        void _clearSliceRTT(size_t zoffset)
        {
            mSliceTRT[zoffset] = 0;
        }
        // Copy from framebuffer
        void copyFromFramebuffer(size_t zoffset);
        /// @copydoc HardwarePixelBuffer::blit
        void blit(const HardwarePixelBufferSharedPtr &src, const Image::Box &srcBox, const Image::Box &dstBox);
        // Blitting implementation
        void blitFromTexture(GLTextureBuffer *src, const Image::Box &srcBox, const Image::Box &dstBox);
    protected:
        // In case this is a texture level
                GLenum mTarget;
                GLenum mFaceTarget; // same as mTarget in case of GL_TEXTURE_xD, but cubemap face for cubemaps
                GLuint mTextureID;
                GLint mFace;
                GLint mLevel;
                bool mSoftwareMipmap;           // Use GLU for mip mapping
        
        typedef std::vector<RenderTexture*> SliceTRT;
        SliceTRT mSliceTRT;
    };
     /** Renderbuffer surface.  Needs FBO extension.
     */
    class _OgrePrivate GLRenderBuffer: public GLHardwarePixelBuffer
        {
    public:
        GLRenderBuffer(GLenum format, size_t width, size_t height);
        ~GLRenderBuffer();
        
        /// @copydoc GLHardwarePixelBuffer::bindToFramebuffer
        virtual void bindToFramebuffer(GLenum attachment, size_t zoffset);
    protected:
        // In case this is a  render buffer
        GLuint mRenderbufferID;
    };
};

#endif