3Delight is a very fast RenderMan-compliant renderer designed to produce photorealistic images for serious production environments. Some of its features include ray tracing, global illumination, motion blur, depth of field, subdivision surfaces, programmable shaders, quality antialiasing, and antialiased multi-depth shadow maps. The API and the shading language are very similar to what is described in the RenderMan interface documentation.
album is a free HTML/XHTML photo album and gallery generator that supports themes/skins. You can choose different themes or write your own to get different layouts and styles. It creates all your thumbnails (including directory thumbnails) and descends into directories so you can organize your photos. See the home page for more examples. album is also multi-lingual, with many languages being added all the time. N.B.: The purchase link is provided for donations; the software does not cost anything.
Allegro is a multi-platform game library for C/C++ developers that provides many functions for graphics, sounds, player input (keyboard, mouse, and joystick), and timers. It also provides fixed and floating point mathematical functions, 3D functions, file management functions, compressed datafile, and a GUI.
Baudline is a time-frequency browser designed for scientific visualization of the spectral domain. Signal analysis is performed by Fourier, correlation, and raster transforms that create colorful spectrograms with vibrant detail. Conduct test and measurement experiments with the built in function generator, or play back audio files with a multitude of effects and filters. The baudline signal analyzer combines fast digital signal processing, versatile high speed displays, and continuous capture tools for hunting down and studying elusive signal characteristics.
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.
CYCAS is a 2D+3D CAD package for drafting and design in high quality and for creating 3D presentations and technical illustrations easily. Some of its features include an easy-to-handle user interface, special architectural elements and functions, a WYSIWYG display, printing, plotting, import and export filters, photorealistic rendering with POV-Ray, documentation and tutorials, example drawings, and an extendable 2D/3D symbols library.