AGP (Accelerated Graphics Port):
This is a new system bus dedicated to graphics. Its main feature is the ability to transfer texture data from the system memory to the graphics controller in real time. AGP has the capacity to use system memory rather than video memory without adversely affecting performance so that 3D performance can benefit from the larger bandwidth.

 

 

Aliasing:
A digital phenomenon. Aliasing can occur where the resolution on a portion of the screen is too low to display its details correctly. Edges are jagged instead of smooth; wavy patterns develop in fine parallel lines. The overall image quality is degraded. The problem is most frequent in diagonal lines.

 

 

Alpha blending:
This technique deals with transparency or opacity effects, for instance when looking through a mirror or underwater. It is thus possible, by pixel modification, to "blend together" several objects. Alpha blending requires a source of red, green, blue and an alpha component and a destination of red, green, blue and an alpha component. The result is that a glass surface or water (source) over an opaque green surface (destination) would filter through much of the base green color. In non-technical terms, the color of the (transparent) object in the forefront is blended with the (opaque) background object in the pixels themselves, consequently offering a high level of rendering.

 

 

Alpha channel:
The alpha channel is an extra 8 bits of information, sent to the screen in the RGB color model. It has uses in numerous special effects, particularly in communicating transparency in objects. An alpha value of 0% would be completely transparent, 100% would be totally opaque, and 50% would be translucent.

 

 

Analog:
A way of representing information (such as the position of a joystick or the height of a sound wave) that uses a continuous range of values. See Digital.

 

 

Anisotropic filtering:
Anisotropic filtering is one level up from trilinear filtering, accomplishing an extremely sharp image by interpolating and filtering multiple samples from one or more mip-maps, thus giving a much better approximation of distorted textures. This requires an extremely large texture memory bandwidth and should only be used if your system can handle it.

 

 

Anti-aliasing:
A filtering procedure designed to eliminate stair-stepping effects which occur at low resolutions and are known as jaggies. It works by blurring pixels at the edges of lines to make the difference between two color areas less dramatic. Most graphics-related programs have an anti-aliasing function, the advantage with 3D Prophet being that it can do this in real time.

 

 

API (Application Programming Interface):
Originally for rich operating systems, a published set of standard routines/functions for a specific task used by developers in their programs to save time. Instead of reinventing all the display tricks each time they want to animate an object in 3D, they use specialized and optimized APIs for 3D. Standards are Direct3D from Microsoft and OpenGL from Silicon Graphics.