ZOE (formerly OGLE) is a simple OpenGL graphics engine written entirely in Python. Its primary focus is rapid prototyping and experimentation, so it only supports the barest essentials, with focus on wire frames. Special emphasis is placed on particle systems (in which non-interacting particles follow simple rules). Some familiarity with OpenGL is expected, although when exploiting the particle system abstractions, no specific OpenGL knowledge is required. The demos included are the obligatory spinning polyhedra, static views of conic sections and the Solar System, a 3D surface plotter, a fountain of sparks, a swarming behavior model, a random walk example, a whirlpool effect using gravity and drag, and an example of chaos theory and sensitivity to initial conditions.
Blender is a free 3D animation studio. It includes tools for modeling, sculpting, texturing (painting, node-based shader materials, or UV mapped), UV mapping, rigging and constraints, weight painting, particle systems, simulation (fluids, physics, and soft body dynamics and an external crowd simulator), rendering, node-based compositing, and non linear video editing, as well as an integrated game engine for real-time interactive 3D, and game creation and playback with cross-platform compatibility.
Moonlight|3D is a modeling and animation tool for three-dimensional art. It currently supports mesh-based modeling. It's a redesign of Moonlight Atelier, formed after Moonlight Atelier/Creator died in 1999/2000. Rendering is done through pluggable backends. It currently supports Sunflow, with support for RenderMan and others in planning.
The OpenVL library is a framework for working with 3D volumetric datasets. It provides a standard and uniform API to volumetric data access, storage, and processing. It is designed and built to be fast, extensible, flexible, and easy to use. The library is completely open-sourced and encourages contribution. This library is an ideal choice if you want to write applications that deal with 3D volumes.
WireFusion allows interactive, plug-in free, and very compact Java presentations and product simulations to be created for the Web. Development involves visually connecting preprogrammed objects or by coding in Java. Several add-ons are available, including a real-time 3D engine where textures can be replaced with interactive 2D presentations, an MPEG video player, a slide show viewer, and an MP3 player.