Computer graphics is the field of synthesising or augmenting imagery through digital means, for artistic, engineering, recreational or scientific purposes.

The first computer graphics were the output of text and numbers on electronic displays, though computer graphics today typically refers to creating images and not text. This field can be divided into two general areas: real-time rendering, and non real-time rendering. Development in computer graphics was first fueled by academic interests and government sponsorship. However, as real-world applications of computer graphics(CG) in broadcast television and movies proved a viable alternative to more traditional special effects and animation techniques, commercial parties have increasingly funded advances in the field.

It is often thought that the first feature film to use computer graphics was 2001: A Space Odyssey, which attempted to show how computers would be much more graphical in the future. However, all the "computer graphic" effects in that film were hand-drawn animation, and the special effects sequences were produced entirely with conventional optical and model effects.

Perhaps the first use of computer graphics specifically to illustrate computer graphics was in Futureworld (1976), which included an animation of a human face and hand - produced by Ed Catmull and Fred Parke at the University of Utah.

2D Computer Graphics

The first advances in computer graphics was in the use of CRTs to represent 2D computer graphics.

3D Computer Graphics

With the birth of the workstation computers (like LISP machines, paintbox computers and Silicon Graphics workstations) came the 3D computer graphics, based on vector representations of virtual objects. (See this article.)

Some major advances in 3D computer graphics have been:

Flat shading

A technique that shades each polygon of an object based on the polygon's "normal" and the position and intensity of a light source.

Gouraud shading

Invented by H. Gouraud in 1971, a fast and resource-conscious vertex shading technique used to simulate smoothly shaded surfaces.

Texture mapping

A technique for simulating a large amount of surface detail by mapping images (textures) onto polygons.

Phong shading

Invented by Wu Tong Phong, used to simulate specular highlights and smooth shaded surfaces.

Bump mapping

Invented by Jim Blinn, a normal-perturbation technique used to simulate wrinkled surfaces.

Raytracing

A shading technique used to simulate reflection and transparency.

Global illumination

Covering the techniques of Monte-Carlo gathering and radiosity for simulating realistic light sources.

Several important topics in 2D and 3D graphics include:

• Color theory
• Raster graphics
• Vector graphics
• Geometric surface representations
• Material properties
• Image compression
• Animation
• Rendering
• Compositing
• Projection

Toolkits and APIs

If you want to build an application that relies heavily on computer graphics you might find the following useful:

• OpenGL
• DirectX
• GKS
• CGM
• PostScript
• X Windows