Xsgi is the

X Window System The X Window System (X11, or simply X) is a windowing system for bitmap displays, common on Unix-like operating systems. X provides the basic framework for a GUI environment: drawing and moving windows on the display device and interacting ...

(X11) server for the

IRIX IRIX ( ) is a discontinued operating system developed by Silicon Graphics (SGI) to run on the company's proprietary MIPS workstations and servers. It is based on UNIX System V with BSD extensions. In IRIX, SGI originated the XFS file system ...

-based graphical workstations and servers from

Silicon Graphics Silicon Graphics, Inc. (stylized as SiliconGraphics before 1999, later rebranded SGI, historically known as Silicon Graphics Computer Systems or SGCS) was an American high-performance computing manufacturer, producing computer hardware and soft ...

(SGI). Xsgi was released in 1991 with IRIX 4.0 on the

SGI Indigo The Indigo, introduced as the IRIS Indigo, is a line of workstation computers developed and manufactured by Silicon Graphics, Inc. (SGI). SGI first announced the system in July 1991. The Indigo is considered one of the most capable graphics ...

workstation.

History

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 John Giannandrea is a Scottish software engineer and businessman. He co-founded Metaweb, led Google Search and artificial intelligence, was co-founder and CTO of the speech recognition company Tellme Networks, Chief Technologist of the web bro ...

, Peter Daifuku, Michael Toy, Todd Newman, Spence Murray, and Dave Spalding. Graphics hardware designed by Silicon Graphics provides accelerated rendering access through graphics hardware commands rather than memory-mapped framebuffers manipulated by the CPU. This makes 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.''Developing NFB graphics adapter drivers''
Silicon Graphics hardware includes overlay planes to provide a

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 im ...

. 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. The previous MIT X sample server treats these two clipping regions as being the identical region. Xsgi advertises overlay planes as X11 visuals with their overlay characteristics described by the convention. Erik Fortune developed the X keyboard extension (XKB) for Xsgi. Xsgi supports the X11,

IRIS GL IRIS GL (Integrated Raster Imaging System Graphics Library) is a proprietary graphics API created by Silicon Graphics (SGI) in the early 1980s for producing 2D and 3D computer graphics on their IRIX-based IRIS graphical workstations. Later SGI re ...

OpenGL OpenGL (Open Graphics Library) is a cross-language, cross-platform application programming interface (API) for rendering 2D and 3D vector graphics. The API is typically used to interact with a graphics processing unit (GPU), to achieve ha ...

Display PostScript Display PostScript (or DPS) is a 2D graphics engine system for computers which uses the PostScript (PS) imaging model and language (originally developed for computer printing) to generate on-screen graphics. To the basic PS system, DPS adds a num ...

, and PEX

PHIGS PHIGS (Programmer's Hierarchical Interactive Graphics System) is an application programming interface (API) standard for rendering 3D computer graphics, considered to be the 3D graphics standard for the 1980s through the early 1990s. Subsequently ...

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. Kilgard, "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'', , pgs. 239–249, 1993. * Elias Israel, Erik Fortune, ''The X Window System Server'', Digital Press, , 1993.

References

External links

Xsgi Man Page
X servers Silicon Graphics {{graphics-software-stub