Some days ago I wanted to get some information on how OpenSceneGraph internally performs the rendering, to prepare for my B.Sc. thesis. Especially I wanted to know if it really uses Vertex Buffer Objects when I “force” Graphics Nodes to do so. Code analysis would have taken to long and would not have been proof enough for me. Thus I needed an OpenGL debugger. A nice one I found is glsldevil, which was developed at the university of Stuttgart. It can not only debug pure OpenGL, but also GLSL shaders.
For gentoo I found an old ebuild somewhere in the web and modified it for the new version of glsldevil. Here is my overlay including the modified ebuild: glsldevil-1.1.5_overlay.tar.gz (1260)
Download the overlay and extract it in /usr/local/portage. Be sure to include the following line in your /etc/make.conf:
Then emerge glsldevil.