IRIS GL
| Company type | Proprietary software |
|---|---|
| Industry | Computer graphics, Software development |
| Founded | 1982 |
| Founder | Silicon Graphics (SGI) |
| Fate | Transformed into OpenGL |
| Products | Graphics API for 2D and 3D graphics |
| Parent | Silicon Graphics (SGI) |
IRIS GL (short for Integrated Raster Imaging System Graphics Library) is a proprietary graphics API created by Silicon Graphics (SGI) in the early 1980s. It was designed to support both 2D and 3D graphics on IRIX-powered IRIS workstations. Eventually, SGI eliminated proprietary elements and restructured system calls, transforming IRIS GL into the widely adopted industry standard known as OpenGL.
History
Development of IRIS GL commenced at SGI in 1982. Its user-friendly and adaptable design quickly made it more popular than the ANSI-standardized PHIGS. SGI licensed IRIS GL to various companies, including IBM, but the existence of diverse implementations and multiple windowing systems led to fragmentation. The launch of the X window system in 1985 offered a more uniform and dependable environment.
A rival technology, X3D—often referred to as the PHIGS Extension To X or PEX—was introduced by Sun Microsystems and Digital Equipment Corporation, heavily relying on the X window system. By the late 1980s, comprehensive PEX implementations were available, motivating IRIS GL developers to pursue an open, portable graphics standard compatible with a wider range of hardware.
In response, SGI initiated the creation of OpenGL in 1989 to address market demands and sustain leadership. Two years later, the OpenGL Architecture Review Board (ARB) was established with representatives from several companies. In September 1991, SGI made IRIS GL generally available under open licensing, receiving endorsements from major firms such as Intel and Microsoft.
The OpenGL 1.0 specification debuted in June 1992, focusing on portability and independence from any specific windowing system—unlike PEX. To avoid naming conflicts, all functions were prefixed with "gl," and many components were simplified or renamed.
Overview
IRIS GL served as a graphics library tailored for IRIX workstations, combining capabilities for window management and input processing.
It included dedicated routines for handling 3D graphics, allowing users to define a 3D transformation that was automatically applied to each vertex. Since programmable shaders were not yet available, shading effects depended on parameters such as diffuse, specular, ambient, and emission properties.
High-level functions like rect enabled developers to specify vertices more efficiently.
Additionally, the library supported fundamental typesetting features using raster fonts and provided tools for working with NURBS curves.
See also
- Silicon Graphics Image, associated with the
.irisfile format - SGI IRIS
- IrisVision, recognized as the initial PC port