#include #include #include #include #include #include #include #include #include #include #include "CreateShadowedScene.h" using namespace osg; class UpdateCameraAndTexGenCallback : public osg::NodeCallback { public: UpdateCameraAndTexGenCallback(const osg::Vec3& position, osg::Camera* Camera, osg::TexGenNode* texgenNode): _position(position), _Camera(Camera), _texgenNode(texgenNode) { } virtual void operator()(osg::Node* node, osg::NodeVisitor* nv) { // first update subgraph to make sure objects are all moved into postion traverse(node,nv); // now compute the camera's view and projection matrix to point at the shadower (the camera's children) osg::BoundingSphere bs; for(unsigned int i=0; i<_Camera->getNumChildren(); ++i) { bs.expandBy(_Camera->getChild(i)->getBound()); } if (!bs.valid()) { osg::notify(osg::WARN) << "bb invalid"<<_Camera.get()<setReferenceFrame(osg::Camera::ABSOLUTE_RF); _Camera->setProjectionMatrixAsFrustum(-right,right,-top,top,znear,zfar); _Camera->setViewMatrixAsLookAt(_position,bs.center(),osg::Vec3(0.0f,1.0f,0.0f)); // compute the matrix which takes a vertex from local coords into tex coords // will use this later to specify osg::TexGen.. osg::Matrix MVPT = _Camera->getViewMatrix() * _Camera->getProjectionMatrix() * osg::Matrix::translate(1.0,1.0,1.0) * osg::Matrix::scale(0.5f,0.5f,0.5f); _texgenNode->getTexGen()->setMode(osg::TexGen::EYE_LINEAR); _texgenNode->getTexGen()->setPlanesFromMatrix(MVPT); } protected: virtual ~UpdateCameraAndTexGenCallback() {} osg::Vec3 _position; osg::ref_ptr _Camera; osg::ref_ptr _texgenNode; }; osg::Group* createShadowedScene(osg::Node* shadower,osg::Node* shadowed,const osg::Vec3& lightPosition,float radius,unsigned int unit) { osg::Group* group = new osg::Group; // add light source { osg::LightSource* lightSource = new osg::LightSource; lightSource->getLight()->setPosition(osg::Vec4(lightPosition,1.0f)); lightSource->getLight()->setLightNum(0); group->addChild(lightSource); osg::Geode* lightgeode = new osg::Geode; lightgeode->getOrCreateStateSet()->setMode(GL_LIGHTING,osg::StateAttribute::OFF); lightgeode->addDrawable(new osg::ShapeDrawable(new osg::Sphere(lightPosition,radius))); group->addChild(lightgeode); } osg::Vec4 ambientLightColor(0.2,0.2f,0.2f,1.0f); // add the shadower and shadowed. group->addChild(shadower); group->addChild(shadowed); unsigned int tex_width = 512; unsigned int tex_height = 512; osg::Texture2D* texture = new osg::Texture2D; texture->setTextureSize(tex_width, tex_height); texture->setInternalFormat(GL_RGB); texture->setFilter(osg::Texture2D::MIN_FILTER,osg::Texture2D::LINEAR); texture->setFilter(osg::Texture2D::MAG_FILTER,osg::Texture2D::LINEAR); texture->setWrap(osg::Texture2D::WRAP_S,osg::Texture2D::CLAMP_TO_BORDER); texture->setWrap(osg::Texture2D::WRAP_T,osg::Texture2D::CLAMP_TO_BORDER); texture->setBorderColor(osg::Vec4(1.0f,1.0f,1.0f,1.0f)); // set up the render to texture camera. { // create the camera osg::Camera* camera = new osg::Camera; camera->setClearColor(osg::Vec4(1.0f,1.0f,1.0f,1.0f)); // set viewport camera->setViewport(0,0,tex_width,tex_height); // set the camera to render before the main camera. camera->setRenderOrder(osg::Camera::PRE_RENDER); // tell the camera to use OpenGL frame buffer object where supported. camera->setRenderTargetImplementation(osg::Camera::FRAME_BUFFER_OBJECT); // attach the texture and use it as the color buffer. camera->attach(osg::Camera::COLOR_BUFFER, texture); // add subgraph to render camera->addChild(shadower); osg::StateSet* stateset = camera->getOrCreateStateSet(); // make the material black for a shadow. osg::Material* material = new osg::Material; material->setAmbient(osg::Material::FRONT_AND_BACK,osg::Vec4(0.0f,0.0f,0.0f,1.0f)); material->setDiffuse(osg::Material::FRONT_AND_BACK,osg::Vec4(0.0f,0.0f,0.0f,1.0f)); material->setEmission(osg::Material::FRONT_AND_BACK,ambientLightColor); material->setShininess(osg::Material::FRONT_AND_BACK,0.0f); stateset->setAttribute(material,osg::StateAttribute::OVERRIDE); group->addChild(camera); // create the texgen node to project the tex coords onto the subgraph osg::TexGenNode* texgenNode = new osg::TexGenNode; texgenNode->setTextureUnit(unit); group->addChild(texgenNode); // set an update callback to keep moving the camera and tex gen in the right direction. group->setUpdateCallback(new UpdateCameraAndTexGenCallback(lightPosition, camera, texgenNode)); } // set the shadowed subgraph so that it uses the texture and tex gen settings. { osg::StateSet* stateset = shadowed->getOrCreateStateSet(); stateset->setTextureAttributeAndModes(unit,texture,osg::StateAttribute::ON); stateset->setTextureMode(unit,GL_TEXTURE_GEN_S,osg::StateAttribute::ON); stateset->setTextureMode(unit,GL_TEXTURE_GEN_T,osg::StateAttribute::ON); stateset->setTextureMode(unit,GL_TEXTURE_GEN_R,osg::StateAttribute::ON); stateset->setTextureMode(unit,GL_TEXTURE_GEN_Q,osg::StateAttribute::ON); } // set hud to render shadow texture, just for interest { osg::Geode* geode = new osg::Geode; osg::Geometry* geom = osg::createTexturedQuadGeometry(osg::Vec3(0,0,0),osg::Vec3(100.0,0.0,0.0),osg::Vec3(0.0,100.0,0.0)); geom->getOrCreateStateSet()->setTextureAttributeAndModes(0,texture,osg::StateAttribute::ON); geom->getOrCreateStateSet()->setMode(GL_LIGHTING,osg::StateAttribute::OFF); geode->addDrawable(geom); osg::Camera* camera = new osg::Camera; // set the projection matrix camera->setProjectionMatrix(osg::Matrix::ortho2D(0,100,0,100)); // set the view matrix camera->setReferenceFrame(osg::Transform::ABSOLUTE_RF); camera->setViewMatrix(osg::Matrix::identity()); camera->setViewport(50,50,100,100); // only clear the depth buffer camera->setClearMask(GL_DEPTH_BUFFER_BIT); // draw subgraph after main camera view. camera->setRenderOrder(osg::Camera::POST_RENDER); camera->addChild(geode); group->addChild(camera); } return group; }