OpenWalnut  1.4.0
WGEOffscreenTexturePass.h
00001 //---------------------------------------------------------------------------
00002 //
00003 // Project: OpenWalnut ( http://www.openwalnut.org )
00004 //
00005 // Copyright 2009 OpenWalnut Community, BSV@Uni-Leipzig and CNCF@MPI-CBS
00006 // For more information see http://www.openwalnut.org/copying
00007 //
00008 // This file is part of OpenWalnut.
00009 //
00010 // OpenWalnut is free software: you can redistribute it and/or modify
00011 // it under the terms of the GNU Lesser General Public License as published by
00012 // the Free Software Foundation, either version 3 of the License, or
00013 // (at your option) any later version.
00014 //
00015 // OpenWalnut is distributed in the hope that it will be useful,
00016 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00017 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00018 // GNU Lesser General Public License for more details.
00019 //
00020 // You should have received a copy of the GNU Lesser General Public License
00021 // along with OpenWalnut. If not, see <http://www.gnu.org/licenses/>.
00022 //
00023 //---------------------------------------------------------------------------
00024 
00025 #ifndef WGEOFFSCREENTEXTUREPASS_H
00026 #define WGEOFFSCREENTEXTUREPASS_H
00027 
00028 #include <string>
00029 
00030 #include <osg/Geode>
00031 #include <osg/TexMat>
00032 
00033 #include "WGEOffscreenRenderPass.h"
00034 
00035 class WGETextureHud;
00036 
00037 /**
00038  * This class encapsulates an OSG Camera and a corresponding framebuffer object. It is a specialized variant of \ref WGEOffscreenRenderPass,
00039  * optimized for processing textures. Therefore, it creates an correctly sized quad and can process each pixel in the fragment shader.
00040  */
00041 class WGEOffscreenTexturePass: public WGEOffscreenRenderPass
00042 {
00043 public:
00044     /**
00045      * Creates a new offscreen rendering instance.
00046      *
00047      * \param textureWidth the width of all the textures created and used by this render pass. This should be large enough for every reasonable
00048      *                     viewport size.
00049      * \param textureHeight the height of all the textures created and used by this render pass. This should be large enough for every reasonable
00050      *                     viewport size.*
00051      * \param num the order number. This camera gets rendered at the num'th place in the pre render queue of the subgraph it is attached to.
00052      */
00053     WGEOffscreenTexturePass( size_t textureWidth, size_t textureHeight, int num = 0 );
00054 
00055     /**
00056      * Creates a new offscreen rendering instance.
00057      *
00058      * \param textureWidth the width of all the textures created and used by this render pass. This should be large enough for every reasonable
00059      *                     viewport size.
00060      * \param textureHeight the height of all the textures created and used by this render pass. This should be large enough for every reasonable
00061      *                     viewport size.*
00062      * \param num the order number. This camera gets rendered at the num'th place in the pre render queue of the subgraph it is attached to.
00063      * \param hud the hud that gets notified about attached and detached textures. Useful for debugging.
00064      * \param name the name of this render pass. This is a nice debugging feature in conjunction with WGETextureHud as it gets displayed there.
00065      */
00066     WGEOffscreenTexturePass( size_t textureWidth, size_t textureHeight, osg::ref_ptr< WGETextureHud > hud, std::string name, int num = 0 );
00067 
00068     /**
00069      * Destructor.
00070      */
00071     virtual ~WGEOffscreenTexturePass();
00072 
00073 protected:
00074 private:
00075     /**
00076      * Sets the whole node up. Used to get some code duplication out of the constructors.
00077      */
00078     void setup();
00079 
00080     /**
00081      * The texture matrix for this pass. Used to scale the texture coordinates according to viewport/texture size relation.
00082      */
00083     osg::ref_ptr< osg::TexMat > m_texMat;
00084 
00085     /**
00086      * Callback which aligns and renders the textures.
00087      */
00088     class TextureMatrixUpdateCallback : public osg::NodeCallback
00089     {
00090     public: // NOLINT
00091         /**
00092          * Constructor.
00093          *
00094          * \param pass the pass to which this callback is applied. Needed for accessing some mebers.
00095          */
00096         explicit TextureMatrixUpdateCallback( WGEOffscreenTexturePass* pass ): m_pass( pass )
00097         {
00098         };
00099 
00100         /**
00101          * operator () - called during the update traversal.
00102          *
00103          * \param node the osg node
00104          * \param nv the node visitor
00105          */
00106         virtual void operator()( osg::Node* node, osg::NodeVisitor* nv );
00107 
00108         /**
00109          * The pass used in conjunction with this callback.
00110          */
00111         WGEOffscreenTexturePass* m_pass;
00112     };
00113 };
00114 
00115 #endif  // WGEOFFSCREENTEXTUREPASS_H
00116