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.
ClanLib is a cross-platform game SDK currently supporting Windows and Linux. It provides easy-to-use interfaces for 2D graphics, input, sound, resources, networking, GUI, OpenGL, and more. The goal is to provide a game SDK that does all the dirty work that all modern games need to implement anyway, thus making the game developer concentrate on the gameplay instead of reinventing the wheel over and over again.
Glt is a library of C++ classes and routines for programming interactive 3D graphics with OpenGL. The aim of Glt is to augment the OpenGL API with convenient mechanisms for manipulating the OpenGL state machine. Glt is a work in progress, and by no means covers the entire OpenGL specification. However, it already includes several useful classes and is designed so that additional classes can be added easily. In addition to Glt, the GlutMaster classes provide C++ wrappers for the GLUT API.
JACL is an interpreted language for creating interactive fiction and turn-based Web games. Using a variety of Glk libraries, JACL has cross-platform support for graphics and sound in the desktop environment. JACL also includes an integrated Web server for easy testing of Web-based games.
Momoko is a generic, object-oriented, modular, extensible environment for creating multi-user environments. It is suitable for writing MUDs, servers, and community-based Web sites. It is written in pure Java and supports Java and Python as internal scripting languages. Momoko provides facilities for organizing objects into tree-based hierarchies, orthogonal persistence, a transparent distributed objects system, remote access to source code and user files via WebDAV, a telnet-enabled shell for manipulating the object database, and an integrated build process which can be triggered remotely.