Multiple windows for OpenGL rendering. Callback driven event processing. Sophisticated input devices. A simple, cascading pop-up menu facility.
Utility routines to generate various solid and wire frame objects.
Support for bitmap and stroke fonts. Miscellaneous window management functions, including managing overlays. An ANSI C implementation of GLUT for the X Window System has been implemented by the author. The result is that OpenGL is win- dow system independent. Window system operations such as the creation of a rendering window and the handling of window system events are left to the native window system to define.