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.
The Chemistry Development Kit (CDK) is a library of Java classes for chemo-, bioinformatics, computational chemistry, and chemometrics. It provides important algorithms like substructure search, SMILES, Gasteiger charges, QSAR descriptor calculation, 3D structure generation, 2D layout and rendering, many IO formats, atom typing, and more.
Dice3DS is a set of Pure Python modules for dealing with 3D Studio format (*.3ds) files. It maps 3DS chunks into a hierarchical set of Python objects; it's a lot like how ElementTree works for XML files. Dice3DS requires Python 2.6 or higher and Numpy. Note that it is not a wrapper for lib3ds.
libQGLViewer is a C++ library based on Qt that eases the creation of OpenGL 3D viewers. It provides some of the typical 3D viewer functionality, such as the ability to move the camera using the mouse, which is lacking in most of the other APIs. Other features include mouse manipulated frames, interpolated keyFrames, object selection, stereo display, screenshot saving, and much more. It can be used by OpenGL beginners as well as to create complex applications, being fully customizable and easy to extend. It ships with many examples and comprehensive documentation.
GL2PS is a C library providing high quality vector output for any OpenGL application. It uses sorting algorithms capable of handling intersecting and stretched polygons, as well as non manifold objects. It provides advanced smooth shading and text rendering, culling of invisible primitives, mixed vector/bitmap output, and much more. It can currently create PostScript (PS), Encapsulated PostScript (EPS), Portable Document Format (PDF), and Scalable Vector Graphics (SVG) files, as well as LaTeX files for the text fragments.