source: GTP/trunk/Lib/Illum/IllumModule/OgreIllumModule/include/RenderTechniques/OgreCausticReceiverRenderTechnique.h @ 2475

#pragma once

//disable inheritance warning caused by multiple inheritance
#if _WIN32
#if _MSC_VER
#pragma warning(disable: 4250)
#endif
#endif

#include "OgreRenderTechnique.h"
#include "CausticReceiverRenderTechnique.h"
#include "Ogre.h"

using namespace Ogre;

/**
        @brief CausticReceiverRenderTechnique used in an OGRE environment.

        This technique defines that the object will recieve caustic lighting from caustic caster objects.
        The caustic light spots will be calculated by the caustic caster's RenderingRuns.
        These runs will only be updated if caustic redievers are visible, so it is the receiver technique's
        responsibility to update them.

        Each caustic caster's light contribution will be added in separate passes. Each pass
        will add some light to the shaded image, so these passes should be the last passes.
        In the constructor the given Pass* parameter will be the pass after which the caustic lighting
        passes will be added by the technique.
*/
class OgreCausticReceiverRenderTechnique : public OgreRenderTechnique,
                                                                                public CausticReceiverRenderTechnique
{
public:
        /**
                @brief Constructor.

                @param maxcasters                               the maximum number of caustic casters from which this receiver can recieve caustic light
                @param causticVertexProgram             the vertex program to be used in the caustic gathering passes
                @param causticFragmentProgram   the fragment program to be used in the caustic gathering passes.
                                                                                It should have one pass and the caustic cubemap of a caster will be bound to the first sampler unit. 
                @param passBlendingSRC                          source blend factor of the new passes
                @param passBlendingDEST                         destination blend factor of the new passes
                @param pass                                             the pass after which caustic gathering passes should be added
                @param parentRenderable                 the object to operate on
                @param parentTechniqueGroup             the TechniqueGroup this RenderedTechnique is attached to
        */
        OgreCausticReceiverRenderTechnique(
                                                        int maxcasters,
                                                        String causticVertexProgram,
                                                        String causticFragmentProgram,
                                                        SceneBlendFactor passBlendingSRC,
                                                        SceneBlendFactor passBlendingDEST,
                                                        bool createNewPasses,
                                                        int startTextureUnitID,
                                                        String casterCenterVariableName,
                                                        String attenuationVariableName,
                                                        bool bindDistanceMap,
                                                        Pass* pass,
                                                        OgreRenderable* parentRenderable,
                                                        OgreTechniqueGroup* parentTechniqueGroup
                                                        );
        /**
                @brief Destructor.
        */
        virtual ~OgreCausticReceiverRenderTechnique();
        
        //inherited
        virtual void update(unsigned long frameNum);
        
protected:
        /**
                @brief the maximum number of caustic casters from which this receiver can recieve caustic light
        */
        int maxcasters;
        /**
                @brief the vertex program to be used in the caustic gathering passes
        */
        String causticVertexProgram;
        /**
                @brief the fragment program to be used in the caustic gathering passes

                It should have one pass and the caustic cubemap of a caster will be bound to the first sampler unit. 
        */
        String causticFragmentProgram;
        /**
                @breif new passes created by this technique
        */
        std::vector<Pass*> passes;
        /**
                @brief the nearest caustic casters found during update
        */
        std::vector<OgreSharedRuns*> causticCasters;
        /**
                @brief source blend factor of the new passes
        */
        SceneBlendFactor passBlendingSRC;
        /**
                @brief destination blend factor of the new passes
        */
        SceneBlendFactor passBlendingDEST;
        bool createNewPasses;
        int startTextureUnitID;
        String casterCenterVariableName;
        String attenuationVariableName;
        bool bindDistanceMap;
        bool bindAttenuation;
};

/**
        @brief RenderTechniqueFactory to create OgreCausticReceiverRenderTechnique instances.
*/
class OgreCausticReceiverRenderTechniqueFactory : public RenderTechniqueFactory
{
public:
        
        OgreCausticReceiverRenderTechniqueFactory();

        OgreRenderTechnique* createInstance(IllumTechniqueParams* params,
                                                                                Pass* pass,
                                                                                OgreRenderable* parentRenderable,
                                                                                OgreTechniqueGroup* parentTechniqueGroup);

        virtual bool needMaterialCopy(IllumTechniqueParams* params){return true;}

        int maxcasters;
        String causticVertexProgram;
        String causticFragmentProgram;
        SceneBlendFactor passBlendingSRC;
        SceneBlendFactor passBlendingDEST;
        bool createNewPasses;
        int startTextureUnitID;
        String casterCenterVariableName;
        String attenuationVariableName;
        bool bindDistanceMap;
};