Method _setTextureCoordCalculation

RenderSystems/GL/src/OgreGLRenderSystem.cpp:1390–1514

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    }
    //-----------------------------------------------------------------------------
    void GLRenderSystem::_setTextureCoordCalculation(size_t stage, TexCoordCalcMethod m,
                                                     const Frustum* frustum)
    {
        if (stage >= mFixedFunctionTextureUnits)
        {
            // Can't do this
            return;
        }

        GLfloat M[16];
        Matrix4 projectionBias;

        // Default to no extra auto texture matrix
        mUseAutoTextureMatrix = false;

        GLfloat eyePlaneS[] = {1.0, 0.0, 0.0, 0.0};
        GLfloat eyePlaneT[] = {0.0, 1.0, 0.0, 0.0};
        GLfloat eyePlaneR[] = {0.0, 0.0, 1.0, 0.0};
        GLfloat eyePlaneQ[] = {0.0, 0.0, 0.0, 1.0};

        mStateCacheManager->activateGLTextureUnit(stage);

        switch( m )
        {
        case TEXCALC_NONE:
            mStateCacheManager->disableTextureCoordGen( GL_TEXTURE_GEN_S );
            mStateCacheManager->disableTextureCoordGen( GL_TEXTURE_GEN_T );
            mStateCacheManager->disableTextureCoordGen( GL_TEXTURE_GEN_R );
            mStateCacheManager->disableTextureCoordGen( GL_TEXTURE_GEN_Q );
            break;

        case TEXCALC_ENVIRONMENT_MAP_PLANAR:
            // should be view position .xy, according to doc, but we want to match OGRE D3D9 behaviour here
        case TEXCALC_ENVIRONMENT_MAP:
            glTexGeni( GL_S, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP );
            glTexGeni( GL_T, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP );

            mStateCacheManager->enableTextureCoordGen( GL_TEXTURE_GEN_S );
            mStateCacheManager->enableTextureCoordGen( GL_TEXTURE_GEN_T );
            mStateCacheManager->disableTextureCoordGen( GL_TEXTURE_GEN_R );
            mStateCacheManager->disableTextureCoordGen( GL_TEXTURE_GEN_Q );

            // Need to use a texture matrix to flip the spheremap
            mUseAutoTextureMatrix = true;
            memset(mAutoTextureMatrix, 0, sizeof(GLfloat)*16);
            mAutoTextureMatrix[0] = mAutoTextureMatrix[10] = mAutoTextureMatrix[15] = 1.0f;
            mAutoTextureMatrix[5] = -1.0f;

            break;

        case TEXCALC_ENVIRONMENT_MAP_REFLECTION:

            glTexGeni( GL_S, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP );
            glTexGeni( GL_T, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP );
            glTexGeni( GL_R, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP );

            mStateCacheManager->enableTextureCoordGen( GL_TEXTURE_GEN_S );
            mStateCacheManager->enableTextureCoordGen( GL_TEXTURE_GEN_T );