BRL-CAD is a powerful constructive solid geometry solid modeling system that includes an interactive geometry editor, ray-tracing support for rendering and geometric analysis, path-tracing for realistic image synthesis, network distributed framebuffer support, and image and signal-processing tools.
Coin is an implementation of Open Inventor. Open Inventor is the de facto standard API for retained-mode 3D graphics programming. Open Inventor has a highly extensible design, and has been designed to allow for rapid development of highly interactive 3D graphics applications in the fields of CAD, engineering, scientific computing, simulation, VRML, and visualization.
K-3D is a 3D modeling, animation, and rendering system for GNU/Linux & Win32. Features include creation and editing of geometry in multiple realtime OpenGL solid, shaded, and texture-mapped views; unlimited undos and redos; complete extensibility at runtime through third-party plugins; animated procedural geometric effects; all parameters animatable through a consistent control-spline based interface; rendering pipeline to Renderman Interface compliant rendering engines; optimization for use with the Aqsis rendering engine, which features solid modelling, true displacement, and user programmable shaders; and support for background and batch rendering.
MagicLight is a 3D modeler, animation system, and renderer. It supports animation, nurbs, free-form deformations, 3D text, and lots of other features. Most of the code is in Java. JOGL is used for 3D display, an internal zbuffer renderer generates high quality images, and an XML format is used for scene descriptions. MagicLight II is a complete redesign of the old version, changing the implementation from C++ to Java.
Verse is a network protocol and client/server application architecture for multiuser realtime distributed 3D graphics applications. It uses a lightweight server to store world data, and then relies on clients to connect and use the data in various ways. Verse uses subdivision surfaces as its single geometric primitive, which both conserves bandwidth and allows very good scalability and visual quality on modern 3D hardware.