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.
Ghostscript is a processor for PostScript and PDF files. It can rasterize these files to a wide variety of printers, devices for screen preview, and image file formats. Since applications tend to prepare pages for printing in a high-level format such as PostScript, most Unix users with low-level bitmap printers, such as inkjets, use GhostScript as part of the printing process. In addition, Ghostscript is capable of converting PostScript files, functionality comparable to Adobe Acrobat Distiller, but on the command line. In addition, Ghostscript is used for file import and viewing by a great many other applications, including xv, ImageMagick, gimp, and xdvi. Several GUI wrappers for viewing PostScript and PDF files exist, including GSview, ghostview, gv, ggv, and kghostview. This is far from a comprehensive list.
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.
aiSee reads a textual, easy-to-read, and easy-to-learn graph specification and automatically calculates a customizable graph layout. This layout is then displayed, and can be printed or interactively explored. aiSee features 15 basic graph layout algorithms (including force-directed layout), recursive subgraph nesting, fish-eye views, and an animation interface. It has been optimized to handle huge graphs automatically generated by applications (e.g. compilers).
white_dune is a graphical VRML97/X3DV editor, simple NURBS/Superformula 3D modeller, animation tool, and VRML97/X3DV commandline compiler in development. VRML97 (Virtual Reality Modeling Language) is the ISO standard for displaying 3D data over the Web via browser plugins ("HTML for realtime 3D"). X3DV is the direct successor of VRML97. VRML97 and X3DV have support for animation, real-time interaction, and multimedia (images, movies, and sounds). white_dune can read, create, and display VRML97/X3DV files and let the user change the scenegraph/fields. It also has support for stereoscopic view via "quadbuffer"-capable stereo visuals, and support for 3D input devices like a joystick, spaceball, or magnetic tracker.