1 Introduction

The OpenGL Utility Toolkit (GLUT) is a programming interface with ANSI C and FORTRAN bindings for writing window system independent OpenGL programs. The toolkit supports the following functionality:

• Multiple windows for OpenGL rendering.
• Callback driven event processing.
• Sophisticated input devices.
• An ``idle'' routine and timers.
• 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.

This documentation serves as both a specification and a programming guide. If you are interested in a brief introduction to programming with GLUT, look for the introductory OpenGL column [8] published in   The X Journal.

The remainder of this section describes GLUT's design philosophy and usage model. The following sections specify the GLUT routines, grouped by functionality. The final sections discuss usage advice, the FORTRAN binding, and implementation issues. Appendix A enumerates and annotates the logical programmer visible state maintained by GLUT. Appendix B presents the ANSI C GLUT API via its header file. Appendix C presents the FORTRAN GLUT API via its header file.

• 1.1 Background
• 1.2 Design Philosophy
• 1.3 API Version 2
• 1.4 API Version 3
• 1.5 Conventions
• 1.6 Terminology