Xsgi
Encyclopedia
Xsgi is the Silicon Graphics
(SGI) implementation of the X Window System
(X11) server for its IRIX
-based IRIS
graphical workstations and servers. Xsgi was released in 1991 with IRIX 4.0 on the IRIS Indigo
workstation.
Work on Xsgi began in May 1989 when Tom Paquin left IBM
to join SGI to integrate the X Window System with SGI's IRIS GL interface. Paquin recruited a set of software engineers experienced in X server implementation: Jeff Weinstein, Erik Fortune, Paul Shupak, John Giannandrea, Peter Daifuku, Michael Toy, Todd Newman, Spence Murray, and Dave Spalding.
Graphics hardware designed by Silicon Graphics provided accelerated rendering access through graphics hardware commands rather than memory-mapped framebuffers manipulated by the CPU. This made the Monochrome FrameBuffer (MFB) and Color FrameBuffer (CFB) device-dependent rendering layers supplied with the MIT X11 Sampler Server inappropriate for Silicon Graphics hardware. Jeff Weinstein developed the No FrameBuffer (NFB) device-dependent rendering layer to support the Silicon Graphics style of hardware access. SCO later incorporated the NFB layer in its X server porting layer .
Silicon Graphics hardware included overlay planes to provide a hardware overlay
. Initial efforts by Todd Newman to implement overlay plane support in Xsgi eventually led to Peter Daifuku's "fully functional" support for overlay planes. Daifuku separated the notion of a window's visibility clipping region from the window's renderable clipping region. Previously the MIT X sample server treated these two clipping regions as being the identical region. Xsgi advertises overlay planes as X11 visuals with their overlay characteristics described by the SERVER_OVERLAY_VISUALS convention.
Eric Fortune developed the X keyboard extension
(XKB) for Xsgi.
Xsgi supports the X11, IRIS GL
, OpenGL
, Display PostScript
, and PEX
rendering models.
Silicon Graphics
Silicon Graphics, Inc. was a manufacturer of high-performance computing solutions, including computer hardware and software, founded in 1981 by Jim Clark...
(SGI) implementation of the X Window System
X Window System
The X window system is a computer software system and network protocol that provides a basis for graphical user interfaces and rich input device capability for networked computers...
(X11) server for its IRIX
IRIX
IRIX is a computer operating system developed by Silicon Graphics, Inc. to run natively on their 32- and 64-bit MIPS architecture workstations and servers. It was based on UNIX System V with BSD extensions. IRIX was the first operating system to include the XFS file system.The last major version...
-based IRIS
SGI IRIS
The SGI IRIS series was a line of terminals and workstations from Silicon Graphics built in the 1980s. They used the Motorola 68000 family of processors originally, but moved to early-generation MIPS processors later on.-External links:***...
graphical workstations and servers. Xsgi was released in 1991 with IRIX 4.0 on the IRIS Indigo
SGI Indigo
The Indigo, introduced as the IRIS Indigo, was a line of workstation computers developed and manufactured by Silicon Graphics, Inc. . The first Indigo, code-named "Hollywood", was introduced on 22 July 1991...
workstation.
Work on Xsgi began in May 1989 when Tom Paquin left IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
to join SGI to integrate the X Window System with SGI's IRIS GL interface. Paquin recruited a set of software engineers experienced in X server implementation: Jeff Weinstein, Erik Fortune, Paul Shupak, John Giannandrea, Peter Daifuku, Michael Toy, Todd Newman, Spence Murray, and Dave Spalding.
Graphics hardware designed by Silicon Graphics provided accelerated rendering access through graphics hardware commands rather than memory-mapped framebuffers manipulated by the CPU. This made the Monochrome FrameBuffer (MFB) and Color FrameBuffer (CFB) device-dependent rendering layers supplied with the MIT X11 Sampler Server inappropriate for Silicon Graphics hardware. Jeff Weinstein developed the No FrameBuffer (NFB) device-dependent rendering layer to support the Silicon Graphics style of hardware access. SCO later incorporated the NFB layer in its X server porting layer .
Silicon Graphics hardware included overlay planes to provide a hardware overlay
Hardware overlay
In computing, hardware overlay, a type of video overlay, provides a method of rendering an image to a display screen with a dedicated memory buffer inside computer video hardware. The technique aims to improve the display of a fast-moving video image — such as a computer game, a DVD, or the signal...
. Initial efforts by Todd Newman to implement overlay plane support in Xsgi eventually led to Peter Daifuku's "fully functional" support for overlay planes. Daifuku separated the notion of a window's visibility clipping region from the window's renderable clipping region. Previously the MIT X sample server treated these two clipping regions as being the identical region. Xsgi advertises overlay planes as X11 visuals with their overlay characteristics described by the SERVER_OVERLAY_VISUALS convention.
Eric Fortune developed the X keyboard extension
X keyboard extension
In human-computer interfaces, the X keyboard extension or XKB is a part of the X Window System that extends the ability to control the keyboard over what is offered by the X Window System core protocol...
(XKB) for Xsgi.
Xsgi supports the X11, IRIS GL
IRIS GL
IRIS GL was a proprietary graphics API created by Silicon Graphics for producing 2D and 3D computer graphics on their IRIX-based IRIS graphical workstations...
, OpenGL
OpenGL
OpenGL is a standard specification defining a cross-language, cross-platform API for writing applications that produce 2D and 3D computer graphics. The interface consists of over 250 different function calls which can be used to draw complex three-dimensional scenes from simple primitives. OpenGL...
, Display PostScript
Display PostScript
Display PostScript is an on-screen display system. As the name implies, DPS uses the PostScript imaging model and language to generate on-screen graphics...
, and PEX
PEX
Cross-linked polyethylene, commonly abbreviated PEX or XLPE, is a form of polyethylene with cross-links. It is formed into tubing, and is used predominantly in hydronic radiant heating systems, domestic water piping and insulation for high tension electrical cables...
rendering models.
Publications
- Jeff Weinstein, "NFB, an X Server Porting Layer," Proceedings of the 6th Annual X Technical Conference appearing in The X Resource, Issue 1, January 1991.
- Mark J. KilgardMark KilgardMark J. Kilgard is a graphics software engineer working at Nvidia.Prior to joining Nvidia, Mark Kilgard worked at Compaq and Silicon Graphics. While at Silicon Graphics, he authored the OpenGL Utility Toolkit, better known as GLUT, to make it easy to write OpenGL-based 3D examples and demos. The...
, "Going Beyond the MIT Sample Server: The Silicon Graphics X11 Server," The X Journal, SIGS Publications, January 1993. - Mark Kilgard, Simon Hui, Allen Leinwand, Dave Spalding, "X Server Multi-rendering for OpenGL and PEX," Proceedings of the 8th Annual X Technical Conference appearing in The X Resource, January 1994.
- Todd Newman, "How Not to Implement Overlays in X," Proceedings of the 6th Annual X Technical Conference appearing in The X Resource, Issue 1, January 1991.
- Peter Daifuku, "A Fully Functional Implementation of Layered Windows," The X Resource, ISBN 1-56592-020-1, pgs. 239-249, 1993.
- Elias Israel, Erik Fortune, The X Window System Server, Digital Press, ISBN 1-55558-096-3, 1993.
See also
- 4Dwm4Dwm4Dwm is a window manager normally used on Silicon Graphics workstations running IRIX. 4Dwm is derived from the older mwm window manager and uses the Motif widget toolkit on top of the X Window System found on most Unix systems....
- 4Sight4Sight4Sight is the name of a desktop computer telephony software product made by 4Com. 4Sight is the name of the client software product. The associated server product is called 4Sight Server. The main purpose of the software is to provide integration between business telephone systems and CRM software...
- Indigo Magic Desktop
- IRIX Interactive DesktopIRIX Interactive DesktopIRIX Interactive Desktop is a desktop environment normally used as the default desktop on Silicon Graphics workstations running IRIX. The IRIX Interactive Desktop uses the Motif widget toolkit on top of the X Window System found on most Unix systems. The default window manager on the IRIX...
- IRIS WorkspaceIRIS WorkspaceThe IRIS WorkSpace is a graphically organized iconic Desktop Environment that allows quick and easy access to the IRIX file system along with simplified system administration via the System Manager. The IRIS WorkSpace was used by Silicon Graphics from 4D1-3.0 - IRIX 5.0...
- MEXMEX (computing)MEX was "Silicon Graphics' original high-performance windowing system", used on 68k-based IRIS systems and early IRIS 4D systems. MEX was originally loaded over a network through the utilization of GL1 routines kept on a remote host machine, usually a VAX. When the IRIS 1400 workstation and GL2-W ...