C++ Shaders::define方法代码示例

void
BumpMapTerrainEffect::onInstall(TerrainEngineNode* engine)
{
    if ( engine && _bumpMapTex.valid() )
    {
        osg::StateSet* stateset = engine->getTerrainStateSet();

        // install the NormalMap texture array:
        if ( engine->getResources()->reserveTextureImageUnit(_bumpMapUnit, "BumpMap") )
        {
            // NormalMap sampler
            _bumpMapTexUniform = stateset->getOrCreateUniform(BUMP_SAMPLER, osg::Uniform::SAMPLER_2D);
            _bumpMapTexUniform->set( _bumpMapUnit );
            stateset->setTextureAttribute( _bumpMapUnit, _bumpMapTex.get(), osg::StateAttribute::ON );

            // configure shaders
            VirtualProgram* vp = VirtualProgram::getOrCreate(stateset);

            Shaders package;            
            package.define( "OE_USE_NORMAL_MAP", engine->normalTexturesRequired() );

            package.loadFunction( vp, package.VertexModel );
            package.loadFunction( vp, package.VertexView );
            package.loadFunction( vp, _octaves <= 1? package.FragmentSimple : package.FragmentProgressive );

            if ( _octaves > 1 )
                stateset->addUniform(new osg::Uniform("oe_bumpmap_octaves", _octaves));

            stateset->addUniform(new osg::Uniform("oe_bumpmap_maxRange", _maxRange));

            stateset->addUniform( _scaleUniform.get() );
            stateset->addUniform( _intensityUniform.get() );
        }
    }
}

void
BumpMapTerrainEffect::onInstall(TerrainEngineNode* engine)
{
    if ( engine && _bumpMapTex.valid() )
    {
        osg::StateSet* stateset = engine->getSurfaceStateSet();

        // install the NormalMap texture array:
        if ( engine->getResources()->reserveTextureImageUnit(_bumpMapUnit, "BumpMap") )
        {
            // NormalMap sampler
            _bumpMapTexUniform = stateset->getOrCreateUniform(BUMP_SAMPLER, osg::Uniform::SAMPLER_2D);
            _bumpMapTexUniform->set( _bumpMapUnit );
            stateset->setTextureAttribute( _bumpMapUnit, _bumpMapTex.get() );

            // configure shaders
            VirtualProgram* vp = VirtualProgram::getOrCreate(stateset);

            Shaders package;            
            package.define( "OE_USE_NORMAL_MAP", false ); //engine->normalTexturesRequired() );

            //package.load( vp, package.VertexModel );
            package.load( vp, package.VertexView );
            package.load( vp, _octaves <= 1? package.FragmentSimple : package.FragmentProgressive );

            if ( _octaves > 1 )
                stateset->addUniform(new osg::Uniform("oe_bumpmap_octaves", _octaves));

            stateset->addUniform(new osg::Uniform("oe_bumpmap_maxRange", _maxRange));
            stateset->addUniform(new osg::Uniform("oe_bumpmap_slopeFactor", 1.0f));
            stateset->addUniform(new osg::Uniform("oe_bumpmap_baseLOD", (float)_baseLOD));

            stateset->addUniform( _scaleUniform.get() );
            stateset->addUniform( _intensityUniform.get() );
        }
        else
        {
            OE_WARN << LC << "Failed to allocation a texture image unit!\n";
        }
    }
}

// Generates the main shader code for rendering the terrain.
void
MPTerrainEngineNode::updateState()
{
    if ( _batchUpdateInProgress )
    {
        _stateUpdateRequired = true;
    }
    else
    {
        if ( _elevationTextureUnit < 0 && elevationTexturesRequired() )
        {
            getResources()->reserveTextureImageUnit( _elevationTextureUnit, "MP Engine Elevation" );
        }

        osg::StateSet* terrainStateSet = getTerrainStateSet();
        
        // required for multipass tile rendering to work
        terrainStateSet->setAttributeAndModes(
            new osg::Depth(osg::Depth::LEQUAL, 0, 1, true) );

        // activate standard mix blending.
        terrainStateSet->setAttributeAndModes( 
            new osg::BlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA),
            osg::StateAttribute::ON );

        // install shaders, if we're using them.
        if ( Registry::capabilities().supportsGLSL() )
        {
            VirtualProgram* vp = new VirtualProgram();
            vp->setName( "osgEarth.engine_mp.TerrainNode" );
            terrainStateSet->setAttributeAndModes( vp, osg::StateAttribute::ON );

            // bind the vertex attributes generated by the tile compiler.
            vp->addBindAttribLocation( "oe_terrain_attr",  osg::Drawable::ATTRIBUTE_6 );
            vp->addBindAttribLocation( "oe_terrain_attr2", osg::Drawable::ATTRIBUTE_7 );

            Shaders package;

            package.replace( "$MP_PRIMARY_UNIT",   Stringify() << _primaryUnit );
            package.replace( "$MP_SECONDARY_UNIT", Stringify() << (_secondaryUnit>=0?_secondaryUnit:0) );

            package.define( "MP_USE_BLENDING", (_terrainOptions.enableBlending() == true) );

            package.loadFunction( vp, package.VertexModel );
            package.loadFunction( vp, package.VertexView );
            package.loadFunction( vp, package.Fragment );
            

            // terrain background color; negative means use the vertex color.
            Color terrainColor = _terrainOptions.color().getOrUse( Color(1,1,1,-1) );
            terrainStateSet->addUniform(new osg::Uniform("oe_terrain_color", terrainColor));

            
            // assemble color filter code snippets.
            bool haveColorFilters = false;
            {
                // Color filter frag function:
                std::string fs_colorfilters =
                    "#version " GLSL_VERSION_STR "\n"
                    GLSL_DEFAULT_PRECISION_FLOAT "\n"
                    "uniform int oe_layer_uid; \n"
                    "$COLOR_FILTER_HEAD"
                    "void oe_mp_apply_filters(inout vec4 color) \n"
                    "{ \n"
                        "$COLOR_FILTER_BODY"
                    "} \n";

                std::stringstream cf_head;
                std::stringstream cf_body;
                const char* I = "    ";

                // second, install the per-layer color filter functions AND shared layer bindings.
                bool ifStarted = false;
                int numImageLayers = _update_mapf->imageLayers().size();
                for( int i=0; i<numImageLayers; ++i )
                {
                    ImageLayer* layer = _update_mapf->getImageLayerAt(i);
                    if ( layer->getEnabled() )
                    {
                        // install Color Filter function calls:
                        const ColorFilterChain& chain = layer->getColorFilters();
                        if ( chain.size() > 0 )
                        {
                            haveColorFilters = true;
                            if ( ifStarted ) cf_body << I << "else if ";
                            else             cf_body << I << "if ";
                            cf_body << "(oe_layer_uid == " << layer->getUID() << ") {\n";
                            for( ColorFilterChain::const_iterator j = chain.begin(); j != chain.end(); ++j )
                            {
                                const ColorFilter* filter = j->get();
                                cf_head << "void " << filter->getEntryPointFunctionName() << "(inout vec4 color);\n";
                                cf_body << I << I << filter->getEntryPointFunctionName() << "(color);\n";
                                filter->install( terrainStateSet );
                            }
                            cf_body << I << "}\n";
                            ifStarted = true;
                        }
                    }
                }
//.........这里部分代码省略.........

// Generates the main shader code for rendering the terrain.
void
RexTerrainEngineNode::updateState()
{
    if ( _batchUpdateInProgress )
    {
        _stateUpdateRequired = true;
    }
    else
    {
        osg::StateSet* terrainStateSet   = _terrain->getOrCreateStateSet();   // everything
        osg::StateSet* surfaceStateSet   = getSurfaceStateSet();    // just the surface
        
        // required for multipass tile rendering to work
        surfaceStateSet->setAttributeAndModes(
            new osg::Depth(osg::Depth::LEQUAL, 0, 1, true) );

        // activate standard mix blending.
        terrainStateSet->setAttributeAndModes( 
            new osg::BlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA),
            osg::StateAttribute::ON );

        // install patch param if we are tessellation on the GPU.
        if ( _terrainOptions.gpuTessellation() == true )
        {
            #ifdef HAVE_PATCH_PARAMETER
              terrainStateSet->setAttributeAndModes( new osg::PatchParameter(3) );
            #endif
        }

        // install shaders, if we're using them.
        if ( Registry::capabilities().supportsGLSL() )
        {
            Shaders package;

            VirtualProgram* terrainVP = VirtualProgram::getOrCreate(terrainStateSet);
            terrainVP->setName( "Rex Terrain" );
            package.load(terrainVP, package.ENGINE_VERT_MODEL);

            //moved to CTOR so it's always available
            //package.load(terrainVP, package.SDK);
            
            bool useTerrainColor = _terrainOptions.color().isSet();
            package.define("OE_REX_USE_TERRAIN_COLOR", useTerrainColor);
            if ( useTerrainColor )
            {
                surfaceStateSet->addUniform(new osg::Uniform("oe_terrain_color", _terrainOptions.color().get()));
            }

            bool useBlending = _terrainOptions.enableBlending().get();
            package.define("OE_REX_GL_BLENDING", useBlending);

            bool morphImagery = _terrainOptions.morphImagery().get();
            package.define("OE_REX_MORPH_IMAGERY", morphImagery);

            // Funtions that affect only the terrain surface:
            VirtualProgram* surfaceVP = VirtualProgram::getOrCreate(surfaceStateSet);
            surfaceVP->setName("Rex Surface");

            // Functions that affect the terrain surface only:
            package.load(surfaceVP, package.ENGINE_VERT_VIEW);
            package.load(surfaceVP, package.ENGINE_FRAG);

            // Normal mapping shaders:
            if ( this->normalTexturesRequired() )
            {
                package.load(surfaceVP, package.NORMAL_MAP_VERT);
                package.load(surfaceVP, package.NORMAL_MAP_FRAG);
            }

            // Morphing?
            if (_terrainOptions.morphTerrain() == true ||
                _terrainOptions.morphImagery() == true)
            {
                package.define("OE_REX_VERTEX_MORPHING", (_terrainOptions.morphTerrain() == true));
                package.load(surfaceVP, package.MORPHING_VERT);
            }

            for(LandCoverZones::iterator zone = _landCoverData._zones.begin(); zone != _landCoverData._zones.end(); ++zone)
            {
                for(LandCoverBins::iterator bin = zone->_bins.begin(); bin != zone->_bins.end(); ++bin)
                {
                    osg::StateSet* landCoverStateSet = bin->_binProto->getStateSet();

                    // enable alpha-to-coverage multisampling for vegetation.
                    landCoverStateSet->setMode(GL_SAMPLE_ALPHA_TO_COVERAGE_ARB, 1);

                    // uniform that communicates the availability of multisampling.
                    landCoverStateSet->addUniform( new osg::Uniform(
                        "oe_terrain_hasMultiSamples",
                        osg::DisplaySettings::instance()->getMultiSamples()) );

                    landCoverStateSet->setAttributeAndModes(
                        new osg::BlendFunc(GL_ONE, GL_ZERO, GL_ONE, GL_ZERO),
                        osg::StateAttribute::OVERRIDE );

                    #ifdef HAVE_OSG_PATCH_PARAMETER
                        landCoverStateSet->setAttributeAndModes( new osg::PatchParameter(3) );
                    #endif
                }
//.........这里部分代码省略.........