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 and art with the aid of computers. Computer graphics is a core technology in digital photography, film, video games, digital art, cell phone and computer displays, and many specialized applications. ...
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 (VLSI) in the early 1980s. A device called the Geometry Engine developed by
Jim Clark
James Clark (4 March 1936 – 7 April 1968) was a British racing driver from Scotland, who competed in Formula One from to . Clark won two Formula One World Drivers' Championship titles with Lotus, and—at the time of his death—held the ...
and
Marc Hannah at
Stanford University
Leland Stanford Junior University, commonly referred to as Stanford University, is a Private university, private research university in Stanford, California, United States. It was founded in 1885 by railroad magnate Leland Stanford (the eighth ...
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, such as preserving distances, angles, or ratios (scale). More specifically, it is a function wh ...
s are applied to the vertices of
polygon
In geometry, a polygon () is a plane figure made up of line segments connected to form a closed polygonal chain.
The segments of a closed polygonal chain are called its '' edges'' or ''sides''. The points where two edges meet are the polygon ...
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 (e.g. 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 straight line perpendicular to the tangent line to the ...
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 daylight. ...
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 an American computer graphics firm founded in 1968 by David C. Evans (computer scientist), David Evans and Ivan Sutherland. Its current products are used in digital projection environments like planetariums. Its simulation b ...
Picture System
An image or picture is a visual representation. An image can be Two-dimensional space, two-dimensional, such as a drawing, painting, or photograph, or Three-dimensional space, three-dimensional, such as a carving or sculpture. Images may be di ...
, 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 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
The computer graphics pipeline, also known as the rendering pipeline, or graphics pipeline, is a framework within computer graphics that outlines the necessary procedures for transforming a three-dimensional (3D) scene into a two-dimensional (2 ...
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 Corporation ( ) is an American multinational corporation and technology company headquartered in Santa Clara, California, and incorporated in Delaware. Founded in 1993 by Jensen Huang (president and CEO), Chris Malachowsky, and Curti ...
and
AMD Graphics
Advanced Micro Devices, Inc. (AMD) is an American multinational corporation and technology company headquartered in Santa Clara, California and maintains significant operations in Austin, Texas. AMD is a hardware and fabless company that des ...
(formerly
ATI) 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 and marketed for the performance market. As of the GeForce 50 series, there have been nineteen iterations of the design. In August 2017, Nvidia stated that "there are o ...
line of
graphics card
A graphics card (also called a video card, display card, graphics accelerator, graphics adapter, VGA card/VGA, video adapter, display adapter, or colloquially GPU) is a computer expansion card that generates a feed of graphics output to a displa ...
s from Nvidia was the first to support full
OpenGL
OpenGL (Open Graphics Library) is a Language-independent specification, cross-language, cross-platform application programming interface (API) for rendering 2D computer graphics, 2D and 3D computer graphics, 3D vector graphics. The API is typic ...
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 ...
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, Inc. was an American computer hardware 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 f ...
,
Matrox
Matrox Graphics, Inc. is a producer of graphics card, 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 ...
and others relied on the
CPU
A central processing unit (CPU), also called a central processor, main processor, or just processor, is the primary processor in a given computer. Its electronic circuitry executes instructions of a computer program, such as arithmetic, log ...
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, information, and automation. Computer science spans Theoretical computer science, theoretical disciplines (such as algorithms, theory of computation, and information theory) to Applied science, ...
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 o ...
*
Graphics pipeline
The computer graphics pipeline, also known as the rendering pipeline, or graphics pipeline, is a framework within computer graphics that outlines the necessary procedures for transforming a three-dimensional (3D) scene into a two-dimensional (2 ...
(include
Pixel pipeline)
*
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