HOOPS 3D graphics system is based in part on the following:

The Freetype Project



Written by Jean-loup Gailly (compression) and Mark Adler (decompression). As quoted from the website, ZLib is “a massively spiffy yet delicately unobtrusive compression library.”


Written and maintained by the open source community. A software suite used to create, edit, and compose bitmap images. It can read, convert and write images in a variety of formats (over 100) including DPX, EXR, GIF, JPEG, JPEG-2000, PDF, PhotoCD, PNG, Postscript, SVG, and TIFF. ImageMagick can be use to translate, flip, mirror, rotate, scale, shear and transform images, adjust image colors, apply various special effects, or draw text, lines, polygons, ellipses and Bezier curves.

Independent JPEG Group

IJG is an informal group that writes and distributes a widely used free library for JPEG image compression.

OpenGL Extension Wrangler Library

GLEW was developed by Milan Ikits and Marcelo Magallon.

The OpenGL Extension Wrangler Library (GLEW) is a cross-platform open-source C/C++ extension loading library. GLEW provides efficient run-time mechanisms for determining which OpenGL extensions are supported on the target platform. GLEW has been tested on a variety of operating systems, including Windows, Linux, Mac OS X, FreeBSD, Irix, and Solaris.”

Frexx C Preprocessor