VisIt is an interactive parallel visualization and graphical analysis tool for viewing scientific data. Users can quickly generate visualizations from their data, animate them through time, manipulate them, and save the resulting images for presentations. VisIt contains a rich set of visualization features so that you can view your data in a variety of ways. It can be used to visualize scalar and vector fields defined on two- and three-dimensional (2D and 3D) structured and unstructured meshes. It was designed to interactively handle very large data set sizes in the terascale range, and works well down to small data sets in the kilobyte range.
GRASS (the Geographic Resources Analysis Support System) is a software raster- and vector-based GIS (Geographic Information System), image processing system, graphics production system, and spatial modeling system. It contains many modules for raster data manipulation, vector data manipulation, rendering images on the monitor or paper, multispectral image geocoding and processing, point data management and general data management. It also has tools for interfacing with digitizers, scanners, and the PostgreSQL, DBF, and ODBC connected databases. GRASS operates on all common operating systems.
VMD (Visual Molecular Dynamics) is designed for the visualization and analysis of biological systems such as proteins, nucleic acids, lipid bilayer assemblies, etc. It may be used to view more general molecules, as VMD can read standard Protein Data Bank (PDB) files and display the contained structure. VMD provides a wide variety of methods for rendering and coloring a molecule: simple points and lines, CPK spheres and cylinders, licorice bonds, backbone tubes and ribbons, cartoon drawings, and others. VMD can be used to animate and analyze the trajectory of a molecular dynamics (MD) simulation. In particular, VMD can act as a graphical front end for an external MD program by displaying and animating a molecule undergoing simulation on a remote computer. VMD uses OpenGL and OpenGL Programmable Shading Language for high performance rendering of large structures.
Python Mesh Viewer is a very basic tool to display and play with 3D models. You can either construct them in the code (by defining points, triangles, and quads) or load them from a file. Currently, the only file format supported is the ".mesh" format from the closed source software medit. The rendering is done with absolutely no hardware acceleration (no OpenGL).
MakeHuman is software for the modelling of three-dimensional humanoid characters. Features that make this software unique include a highly intuitive GUI and a high quality mesh, optimized to work in subdivision surface mode (for example, Zbrush). Using MakeHuman, a photo-realistic character can be modelled in less than 2 minutes.
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.
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.