Geometric manipulation of modelling primitives, such as that performed by a geometry pipeline, is the first stage in
computer graphics
Computer graphics deals with generating images with the aid of computers. Today, computer graphics is a core technology in digital photography, film, video games, cell phone and computer displays, and many specialized applications. A great de ...
systems which perform image generation based on geometric models. While geometry pipelines were originally implemented in software, they have become highly amenable to hardware implementation, particularly since the advent of
very-large-scale integration
Very large-scale integration (VLSI) is the process of creating an integrated circuit (IC) by combining millions or billions of MOS transistors onto a single chip. VLSI began in the 1970s when MOS integrated circuit (Metal Oxide Semiconductor) c ...
(VLSI) in the early 1980s. A device called the Geometry Engine developed by
Jim Clark
James Clark Jr. OBE (4 March 1936 – 7 April 1968) was a British Formula One racing driver from Scotland, who won two World Championships, in 1963 and 1965. A versatile driver, he competed in sports cars, touring cars and in the Indianapol ...
and Marc Hannah at
Stanford University
Stanford University, officially Leland Stanford Junior University, is a private research university in Stanford, California. The campus occupies , among the largest in the United States, and enrolls over 17,000 students. Stanford is consider ...
in about 1981 was the watershed for what has since become an increasingly commoditized function in contemporary image-synthetic
raster display systems.
[
]
Geometric transformation
In mathematics, a geometric transformation is any bijection of a set to itself (or to another such set) with some salient geometrical underpinning. More specifically, it is a function whose domain and range are sets of points — most often ...
s are applied to the vertices of
polygon
In geometry, a polygon () is a plane figure that is described by a finite number of straight line segments connected to form a closed ''polygonal chain'' (or ''polygonal circuit''). The bounded plane region, the bounding circuit, or the two toge ...
s, or other geometric objects used as
modelling primitives, as part of the first stage in a classical geometry-based graphic image
rendering pipeline. Geometric computations may also be applied to transform polygon or repair
surface normal
In geometry, a normal is an object such as a line, ray, or vector that is perpendicular to a given object. For example, the normal line to a plane curve at a given point is the (infinite) line perpendicular to the tangent line to the curve at ...
s, and then to perform the
lighting
Lighting or illumination is the deliberate use of light to achieve practical or aesthetic effects. Lighting includes the use of both artificial light sources like lamps and light fixtures, as well as natural illumination by capturing daylig ...
and
shading
Shading refers to the depiction of depth perception in 3D models (within the field of 3D computer graphics) or illustrations (in visual art) by varying the level of darkness. Shading tries to approximate local behavior of light on the object's ...
computations used in their subsequent rendering.
History
Hardware implementations of the geometry pipeline were introduced in the early
Evans & Sutherland
Evans & Sutherland is a pioneering American computer firm in the computer graphics field. Its current products are used in digital projection environments like planetariums. Its simulation business, which it sold to Rockwell Collins, sold products ...
Picture System
An image is a visual representation of something. It can be two-dimensional, three-dimensional, or somehow otherwise feed into the visual system to convey information. An image can be an artifact, such as a photograph or other two-dimensiona ...
, but perhaps received broader recognition when later applied in the broad range of graphics systems products introduced by
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). Initially the SGI geometry hardware performed simple
model space
A model is an informative representation of an object, person or system. The term originally denoted the Plan_(drawing), plans of a building in late 16th-century English, and derived via French and Italian ultimately from Latin ''modulus'', a mea ...
to
screen space
This is a glossary of terms relating to computer graphics.
For more general computer hardware terms, see glossary of computer hardware terms.
0–9
A
B
...
viewing transformation
In computer graphics, a computer graphics pipeline, rendering pipeline or simply graphics pipeline, is a conceptual model that describes what steps a graphics system needs to perform to render a 3D scene to a 2D screen. Once ...
s with all the lighting and shading handled by a separate hardware implementation stage. In later, much higher performance applications, such as the
RealityEngine
RealityEngine is a 3D graphics hardware architecture and a family of graphics systems which was developed and manufactured by Silicon Graphics during the early to mid 1990s. RealityEngine was positioned as the company's high-end visualization har ...
, they began to be applied to perform part of the rendering support as well.
More recently, perhaps dating from the late 1990s, the hardware support required to perform the manipulation and rendering of quite complex scenes has become accessible to the consumer market.
Companies such as
Nvidia
Nvidia CorporationOfficially written as NVIDIA and stylized in its logo as VIDIA with the lowercase "n" the same height as the uppercase "VIDIA"; formerly stylized as VIDIA with a large italicized lowercase "n" on products from the mid 1990s to ...
and
AMD Graphics (formerly
ATI
Ati or ATI may refer to:
* Ati people, a Negrito ethnic group in the Philippines
**Ati language (Philippines), the language spoken by this people group
** Ati-Atihan festival, an annual celebration held in the Philippines
*Ati language (China), a ...
) are two current leading representatives of hardware vendors in this space. The
GeForce
GeForce is a brand of graphics processing units (GPUs) designed by Nvidia. As of the GeForce 40 series, there have been eighteen iterations of the design. The first GeForce products were discrete GPUs designed for add-on graphics boards, inten ...
line of
graphics card
A graphics card (also called a video card, display card, graphics adapter, VGA card/VGA, video adapter, display adapter, or mistakenly GPU) is an expansion card which generates a feed of output images to a display device, such as a computer moni ...
s from Nvidia was the first to support full
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 hardwa ...
and
Direct3D
Direct3D is a graphics application programming interface (API) for Microsoft Windows. Part of DirectX, Direct3D is used to render three-dimensional graphics in applications where performance is important, such as games. Direct3D uses hardware a ...
hardware geometry processing in the consumer PC market, while some earlier products such as Rendition Verite incorporated hardware geometry processing through proprietary programming interfaces. On the whole, earlier graphics accelerators by
3Dfx
3dfx Interactive was an American technology company headquartered in San Jose, California, founded in 1994, that specialized in the manufacturing of 3D graphics processing units, and later, video cards. It was a pioneer in the field from the l ...
,
Matrox
Matrox Graphics, Inc. is a producer of video card components and equipment for personal computers and workstations. Based in Dorval, Quebec, Canada, it was founded in 1976 by Lorne Trottier and Branko Matić. The name is derived from "Ma" in Mat ...
and others relied on the
CPU for geometry processing.
This subject matter is part of the technical foundation for modern computer graphics, and is a comprehensive topic taught at both the undergraduate and graduate levels as part of a
computer science
Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical discipli ...
education.
See also
*
Vertex pipeline The function of the vertex pipeline in any GPU is to take geometry data (usually supplied as vector points), work with it if needed with either fixed function processes (earlier DirectX), or a vertex shader program (later DirectX), and create all of ...
*
Graphics pipeline
In computer graphics, a computer graphics pipeline, rendering pipeline or simply graphics pipeline, is a conceptual model that describes what steps a graphics system needs to perform to Rendering (computer graphics), render a ...
(include
Pixel pipeline
In computer graphics, a computer graphics pipeline, rendering pipeline or simply graphics pipeline, is a conceptual model that describes what steps a graphics system needs to perform to Rendering (computer graphics), render a ...
)
*
Rasterisation
In computer graphics, rasterisation (British English) or rasterization (American English) is the task of taking an image described in a vector graphics format (shapes) and converting it into a raster image (a series of pixels, dots or lines, whic ...
*
Open Graphics Project
The Open Graphics Project (OGP) was founded with the goal to design an open-source hardware / open architecture and standard for graphics cards, primarily targeting free software / open-source operating systems. The project created a reprogramma ...
References
{{Graphics Processing Unit
3D computer graphics