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.
The Geospatial Data Abstraction Library (GDAL) is a unifying C/C++ API for accessing raster geospatial data, and currently includes formats like GeoTIFF, Erdas Imagine, Arc/Info Binary, CEOS, DTED, GXF, and SDTS. It is intended to provide efficient access, suitable for use in viewer applications, and also attempts to preserve coordinate systems and metadata. Python, C, and C++ interfaces are available.
Noptec Vector is an implementation of a bitmap vectorizing algorithm, specifically for creating background picture resources for the Sierra AGI interpreter. The program reads an image in BMP, PCX, or TGA format, converts it to 160 x 168 x 16 colors and writes the result in AGI readable format, optionally showing the result onscreen.
PLIB is a set of libraries to write games and other realtime interactive applications that are 100% portable across a wide range of hardware and operating systems. It's used by Majik3D, FlightGear, and others, and includes libraries for GUI widgets, sound replay, geometry, scene graph, joystick, and fonts/text.
Xpdf is a viewer for Portable Document Format (PDF) files. (These are also sometimes also called 'Acrobat' files, from the name of Adobe's PDF software.) The Xpdf project also includes a PDF text extractor, PDF-to-PostScript converter, and various other utilities. It runs under the X Window System on UNIX, VMS, and OS/2. The non-X components (pdftops, pdftotext, etc.) also run on Win32 systems, and should run on pretty much any system with a decent C++ compiler. Xpdf is designed to be small and efficient. It can use Type 1 and TrueType fonts.
pad sequential filenames so alphabetical order matches numerical order. It automatically determines the necessary integer field width, treats filenames with different prefixes or suffixes separately, removes redundant padding, and is reasonably efficient, even for thousands of names.
im2avi is a small program for making AVIs from sequences of images. It makes use of avifile for encoding video streams, so im2avi has access to all the codecs that avifile supports, including DivX ;) or Cinepak. It uses the ImageMagick++ library to load the images, so it supports a wide range of formats.