Computer graphics

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This article is about the scientific discipline of computer graphics. For a more general information on computer graphics and applications, see 2D computer graphics and 3D computer graphics

Computer graphics is a sub-field of computer science and is concerned with digitally synthesizing and manipulating visual content. Although the term often refers to three-dimensional computer graphics, it also encompasses two-dimensional graphics and image processing. Computer graphics is often differentiated from the field of visualization, although the two have many similarities.

A broad classification of major subfields in computer graphics might be:

  1. Geometry: studies ways to represent and process surfaces
  2. Animation: studies with ways to represent and manipulate motion
  3. Rendering: studies algorithms to reproduce light transport


The Utah teapot
The Utah teapot

Contents

[edit] Geometry

The subfield of geometry studies the representation of three-dimensional objects in a discrete digital setting. Because the appearance of an object depends largely on the exterior of the object, boundary representations are most common in computer graphics. Two dimensional surfaces are a good analogy for the objects most often used in graphics, though quite often these objects are non-manifold. Since surfaces are not finite, a discrete digital approximation is required: polygonal meshes (and to a lesser extent subdivision surfaces) are by far the most common representation, although point-based representations have been gaining some popularity in recent years (see the Symposium on Point-Based Graphics[1], for instance). These representations are Lagrangian, meaning the spatial locations of the samples are independent. In recent years, however, Eulerian surface descriptions (i.e., where spatial samples are fixed) such as level sets have been developed into a useful representation for deforming surfaces which undergo many topological changes (with fluids being the most notable example[2]).

[edit] Subfields

  • Constructive solid geometry - Process by which complicated objects are modelled with implicit goemetric ojects and boolean operations
  • Discrete differential geometry - a nascent field which defines geometric quantities for the discrete surfaces used in computer graphics[3].
  • Digital geometry processing - surface reconstruction, simplification, fairing, mesh repair, parameterization, remeshing, mesh generation, surface compression, and surface editing all fall under this heading [4][5][6].
  • Point-based graphics - a recent field which focuses on points as the fundamental representation of surfaces.
  • Simulation (e.g. cloth modeling, animation of fluid dynamics, etc.)
  • Subdivision surfaces

[edit] Animation

The subfield of animation studies descriptions for surfaces (and other phenomena) that move or deform over time. Historically most interest in this area has been focused on parametric and data-driven models, but in recent years physical simulation has experienced a renaissance due to the growing computational capacity of modern machines.

[edit] Rendering

Rendering converts a model into an image either by simulating light transport to get physically-based photorealistic images, or by applying some kind of style as in non-photorealistic rendering. The two basic operations in realistic rendering are transport (how much light gets from one place to another) and scattering (how surfaces interact with light). See Rendering (computer graphics) for more information.

[edit] Transport

Transport describes how illumination in a scene gets from one place to another. Visibility is a major component of light transport.

[edit] Scattering

Models of scattering and shading are used to describe the appearance of a surface. Although these issues may seem like a problems all on their own, they are studied almost exclusively within the context of rendering[citation needed]. Shading can be broken down into two orthogonal issues, which are often studied independently:

  1. scattering - how light interacts with the surface at a given point
  2. shading - how material properties vary across the surface

The former problem refers to scattering, i.e., the relationship between incoming and outgoing illumination at a given point. Descriptions of scattering are usually given in terms of a bidirectional scattering distribution function or BSDF. The latter issue addresses how different types of scattering are distributed across the surface (i.e., which scattering function applies where). Descriptions of this kind are typically expressed with a program called a shader. (Note that there is some confusion since the word "shader" is sometimes used for programs that describe local geometric variation.)

[edit] Other Subfields

  • physically-based rendering - concerned with generating images according to the laws of geometric optics
  • real time rendering - focuses on rendering for interactive applications, typically using specialized hardware like GPUs
  • non-photorealistic rendering
  • relighting - recent area concerned with quickly re-rendering scenes

[edit] History

William Fetter was credited with coining the term Computer Graphics in 1960, to describe his work at Boeing. One of the first displays of computer animation was Futureworld (1976), which included an animation of a human face and hand — produced by Ed Catmull and Fred Parke at the University of Utah.

There are several international conferences and journals where the most significant results in computer graphics are published. Among them are the SIGGRAPH and Eurographics conferences and the ACM Transactions on Graphics journal. The joint Eurographics and ACM SIGGRAPH symposium series features the major venues for the more specialized sub-fields: Symposium on Geometry Processing [7], Symposium on Rendering, and Symposium on Computer Animation.[8]

An extensive history of computer graphics can be found at [9].

[edit] Applications

[edit] Connected Studies

[edit] Computer Graphics Research Groups

[edit] Academia

The number of computer science departments with computer graphics groups has grown rapidly over the past two decades. A partial list of departments notably involved in graphics research includes:

  • Berkeley Computer Modeling and Animation Group [10]
  • C2G2 at Columbia University [11]
  • Caltech Multi-Res Modeling Group [12]
  • Carnegie Mellon Graphics Lab [13]
  • Computer Graphics Department at Max-Planck-Institut fur Informatik [14]
  • Computer Graphics Group at Brown [15]
  • Computer Graphics at Harvard [16]
  • Computer Graphics Laboratory at Korea Advanced Institute of Science and Technology (KAIST) [17]
  • Computer Graphics Laboratory at University of Tokyo [18]
  • Computer Graphics Laboratory at UT Austin [19]
  • Computer Graphics / Geometric Design Group at Rice [20]
  • Computer Graphics and User Interfaces Lab at Columbia University [21]
  • Computer Graphics and Visualization Lab at University of Utah [22]
  • Computer Graphics and Visualization Lab at University of Wisconsin [23]
  • Cornell University Program of Computer Graphics [24]
  • Dynamic Graphics Project at University of Toronto [25]
  • Geometric Modeling and Industrial Geometry Group at Technische Universitat Wien [26]
  • Graphics and Image Analysis at UNC [27]
  • Graphics and Geometric Computing Group at Tsinghua University [28]
  • Graphics@Illinois [29]
  • GRAIL at University of Washington [30]
  • GRAVIR at iMAGIS [www-gravir.imag.fr]
  • GVU Center at Georgia Tech [31]
  • IDAV Visualization and Graphics Research Group at UC Davis [32]
  • Imager Laboratory at University of British Columbia [33]
  • MIT Computer Graphics Group [34]
  • MRL at NYU [35]
  • Princeton Graphics and Geometry Group [36]
  • Stanford Computer Graphics Laboratory [37]
  • UCSD Computer Graphics Laboratory [38]
  • Vision Research Center at Vanderbilt [39]

[edit] Industry

Industrial labs doing "blue sky" graphics research include:

  • Adobe Research
  • MERL [40]
  • Microsoft Research - Graphics [41]
  • NVIDIA Research

Major film studios notable for graphics research include:

[edit] Notable People in Computer Graphics

(Based on paper citations - see [45])

[edit] See also

Numerous sub-areas of computer graphics can be found in Category:3D computer graphics.

[edit] External links

Look up computer graphics in Wiktionary, the free dictionary.
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