PHIGS (Programmer's Hierarchical Interactive Graphics System)
Gimpel3D - 2D/3D Stereo Conversion Editor
Support for jgeom, the java geometry graphics library using NURBS
Megalui: 2D/3D OpenGL & C/C++ Library for Scientific Visualizations
Displays your photos on the walls of a maze
An OpenGL sample application
A C++ library to easily create GUI-editable objects
diagrammatic 3D in a web browser using SVG
Obsolete: use https://github.com/VMML/vmmlib