Hi Shuiying 2) geometry shader. You can create one with osg::Shader* sh = new osg::Shader(osg::Shader::GEOMETRY) usage same as with other osg shaders in cpp code 3) If they are supported by your opengl implementation: a) you should use declaration of shader version where they are supported with "#version 400" (iirc this is first version with double support in gl core) in your shaders (must be first line on some platforms) OR b) you should enable extension GL_ARB_gpu_shader_fp64 which enables double's support in glsl with "#extension GL_ARB_gpu_shader_fp64 : enable"
Cant say anything about 1st question. Cheers 12.01.2012, 22:14, "wang shuiying" <shuiying.w...@fu-berlin.de>: > Hi, > > Thank you all a lot for your help. That really helps me a lot. > > Now I know that polygon triangulation and rasterization algorithms have > something to do with the imperfectness of my programm. > > I have some other questions: > > (1) > According to triangle raterization function (3.9), p185 in > > http://www.opengl.org/registry/doc/glspec42.core.20110808.pdf > > if the eye direction of osg camera is on the same line with the > polygon normal vector, there would be less distortion in the generated > fragment attributes (in my case, the eyecoord position corresponding to > each fragement) than if they are not on the same line. > > Is the conclusion I said above right? > > (2) > in > > http://www.opengl.org/registry/doc/glspec42.core.20110808.pdf > > on P.7, there is a geometry processor, which is notated as a Programmable > unit. Is it possible to use this programmable unit as the way vertex and > fragment shader are used in open scene graph? > > (3) > also in > > http://www.opengl.org/registry/doc/glspec42.core.20110808.pdf > on P.19, it is said that the variable type include double. But when I change > float into double in my shader, the programme doesn't work. Why? It is not > possible to use double type in Open scene graph? > > Thank you in advance! > > Shuiying > > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
