Hi, Felix First, you should bind fragment shader output with osg::Program::addBindFragDataLocation (const std::string &name, GLuint index). Then to check if your shaders have eny effect you can just output different color from your fragment shader and look if it make any difference.
Then, your shader is just bypassing interpolated osg_Color, which is essentially per-vertex color attribute. osg::ShapeDrawables use this for coloring, but most models dont have per-vertex colors, so this can brake things (like you can get last applied color array binded to all geometry which doesnt have one itself, or you can get undefined\random values). If you want to get textures\lighting\etc working you should implement all of these in shader yourself. Cheers, Sergey. 20.07.2012, 16:08, "Felix Meißgeier" <[email protected]>: > Hey, > > i've got question relating to a simple shader-implementation (#version 140) > in OSG. I just want to render a scene without any modifications but by > passing a vertex- and fragment-shader. Because I'm working with the third > edition of the Orange-Book I want to use this "newer" glsl-version. > > here is my code so far: > > .cpp > > Code: > > int _tmain(int argc, _TCHAR* argv[]) > { > osg::setNotifyLevel( osg::WARN ); > osg::ref_ptr<osg::GraphicsContext::Traits> gctraits = new > osg::GraphicsContext::Traits(); > gctraits->x=50; > gctraits->y=50; > gctraits->width=1280; > gctraits->height=1024; > gctraits->windowDecoration=true; > gctraits->doubleBuffer=true; > > osg::ref_ptr<osg::GraphicsContext> gc = > osg::GraphicsContext::createGraphicsContext(gctraits.get()); > //set fixed functionality vars > gc->getState()->setUseModelViewAndProjectionUniforms(true); > gc->getState()->setUseVertexAttributeAliasing(true); > > osg::ref_ptr<osg::Camera> cam = new osg::Camera(); > cam->setGraphicsContext(gc.get()); > cam->setViewport(new osg::Viewport(0,0,gctraits->width, gctraits->height)); > cam->setClearMask(GL_DEPTH_BUFFER_BIT|GL_COLOR_BUFFER_BIT); > cam->setClearColor(osg::Vec4(0.2,0.2,0.4,1.0)); > cam->setProjectionMatrixAsPerspective(30.0,(double)gctraits->width/gctraits->height,1.0,1000.0); > > //setup scene > osg::ref_ptr<osg::Group> root = new osg::Group(); > osg::ref_ptr<osg::Node> cessna = new osg::Node(); > osg::ref_ptr<osg::Node> landscape = new osg::Node(); > osg::ref_ptr<osg::Geode> sphere = new osg::Geode(); > osg::ref_ptr<osg::PositionAttitudeTransform> cessnatransform = new > osg::PositionAttitudeTransform(); > osg::ref_ptr<osg::PositionAttitudeTransform> spheretransform = new > osg::PositionAttitudeTransform(); > osg::ref_ptr<osg::PositionAttitudeTransform> landscapetransform = new > osg::PositionAttitudeTransform(); > > landscape = osgDB::readNodeFile("osgdata/lz.osg"); > cessna = osgDB::readNodeFile("osgdata/cessna.osg"); > osg::ref_ptr<osg::ShapeDrawable> sphereshape = new osg::ShapeDrawable(new > osg::Sphere(osg::Vec3(0.0f,0.0f,0.0f),5.0f)); > sphereshape->setColor(osg::Vec4(0.0f,1.0f,0.0f,0.5f)); > sphere->addDrawable(sphereshape.get()); > > cessnatransform->setPosition(osg::Vec3(100.0f,0.0f,150.0f)); > spheretransform->setPosition(osg::Vec3(50.0f,0.0f,150.0f)); > landscapetransform->setPosition(osg::Vec3(0.0f,0.0f,0.0f)); > > cessnatransform->addChild(cessna.get()); > landscapetransform->addChild(landscape.get()); > spheretransform->addChild(sphere.get()); > root->addChild(landscapetransform.get()); > root->addChild(cessnatransform.get()); > root->addChild(spheretransform.get()); > > //setup shaders > osg::ref_ptr<osg::Shader> vertshader = new osg::Shader(osg::Shader::VERTEX); > if(!vertshader->loadShaderSourceFromFile(VSSRCFILE)) > osg::notify(osg::WARN)<<"Error while loading vertexshader-sourcefile..."; > osg::ref_ptr<osg::Shader> fragshader = new > osg::Shader(osg::Shader::FRAGMENT); > if(!fragshader->loadShaderSourceFromFile(FSSRCFILE)) > osg::notify(osg::WARN)<<"Error while loading > fragmentshader-sourcefile..."; > osg::ref_ptr<osg::Program> shaderprog = new osg::Program(); > shaderprog->addShader(vertshader.get()); > shaderprog->addShader(fragshader.get()); > root->getOrCreateStateSet()->setAttributeAndModes(shaderprog.get()); > > osgViewer::Viewer viewer; > viewer.setCamera(cam.get()); > viewer.setSceneData(root.get()); > viewer.setCameraManipulator(new osgGA::TerrainManipulator); > viewer.getCameraManipulator()->setHomePosition(osg::Vec3(250.0,-200.0,143.0),osg::Vec3(23.0,8.0,143.0),osg::Vec3(0.0,0.0,1.0)); > > return viewer.run(); > } > > vertexshader > > Code: > > #version 140 > > uniform mat4 osg_ModelViewProjectionMatrix; > in vec4 osg_Color; > in vec4 osg_Vertex; > > out vec4 fragcolor; > > void main(){ > fragcolor=osg_Color; > gl_Position=osg_ModelViewProjectionMatrix*osg_Vertex; > } > > fragment-shader > > Code: > > #version 140 > > in vec4 fragcolor; > > out vec4 fragData; > > void main(){ > fragData=fragcolor; > } > > My problem is, that the rendering-result is not the same as I expected. I > have attached to pictures to this post. When I run the program with the use > of the methods "setUseModelViewAndProjectionUniforms(true)" and > "setUseVertexAttributeAliasing(true)" it seems that the vertices of the > models (texture-based fragments) were not processed by the shaders (because > they are white). The other picture visualizes the scene without the using of > shaders. > Because of the fact, that in all probability my understanding of this topic > is not correct and my code is buggy, I would be glad, if someone could > comment my mistakes or missapprehensions. > > Thank you! > > regards, > Felix > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=48953#48953 > > Attachments: > http://forum.openscenegraph.org//files/shader_used_186.jpg > http://forum.openscenegraph.org//files/without_shader_696.jpg > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
