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.
The GNU Triangulated Surface Library (GTS) provides a set of useful functions to deal with 3D surfaces meshed with interconnected triangles. It features metric operations (area, volume, curvature, etc.), 2D Delaunay and constrained Delaunay triangulations, robust geometric predicates and set operations on surfaces (union, intersection, etc.), surface refinement and coarsening (multiresolution models), and bounding-boxes trees for collision/intersection detection.
Teddy is an OpenGL-based 3D graphics library written in C++. Its main features are simple scene graph and windowing system-enabling multiple cameras, camera windows, and scenes. It focuses on easy and flexible manipulation of models and model materials in the scene graph. It contains a number of primitive objects like sphere, box, and cone, and it can load LightWave object and scene files.
The Java 3D API enables the creation of three-dimensional graphics applications and Internet-based 3D applets. It provides high-level constructs for creating and manipulating 3D geometry and building the structures used in rendering that geometry. With this software, you can efficiently define and render very large virtual worlds. Blackdown's version of Java 3D uses the OpenGL low-level API to take advantage of 3D hardware acceleration.
The Interreality project is a collection of Open Source, Free Software projects based on the Virtual Object System (VOS) platform. The goal is to develop a free and open platform for multi-user 3D virtual reality games, applications, and interactive, collaborative 3D virtual spaces. VOS is a powerful and generic network object framework designed to support a variety of high-performance applications. It is the basis for Ter'Angreal, a general-purpose browser application for entering and participating in 3D worlds.
L3D is a 3D library for developing OpenGL applications under Linux. The library has a main display loop, and call-back functions similar to those in GLUT. It has a graphical console for output of information. The goal of this project is a library which is small and hopefully scalable.