Glossary

AGP

Accelerated Graphics Port; a high-performance bus designed specifically for graphical devices.

alpha-blending

A technique of portraying transparency when drawing an object. It combines the color of an object to be drawn (the source) and the color of whatever the object is to be drawn on top of (the destination). The higher the blending factor of the source object, the more opaque the object looks.

Mathematically, a blending factor is a real number between 0 and 1, inclusive. These are normally mapped to the range 0-0xFF for storage purposes in a 2D library. A 32-bit color is made up of four 8-bit channels: alpha, red, green, and blue. These channels are represented as (A, R, G, B). When referring to the source, the channels are denoted as As, Rs, Gs, and Bs; for the destination, they're Ad, Rd, Gd, and Bd.

BIOS

Basic Input/Output System; standard ROM services that are available on x86 platforms.

blitting

BLock Image Transfer; copying an image from one place on the screen to another.

chroma keying

A method of masking out pixel data during a rendering operation (blits, image rendering, etc.) based on a key color value.

CRTC

Cathode-Ray Tube Controller.

DPMS

Display Power Management System; a system that reduces the amount of energy consumed by a monitor when it's idle.

falling back on software

Using software to perform operations that the graphics hardware doesn't support.

FFB

Flat Frame Buffer

PCI

Peripheral Components Interface; a general-purpose system bus that's found in most modern PCs.

raster operations (ROP)

A per-pixel operation to be performed when rendering an object. A raster operation may involve up to three input parameters (source, pattern, and destination) that are combined in accordance with the raster operation that's currently in effect. The resulting pixel value is written to the destination.

ROP3

A set of 256 raster operations, as defined by Microsoft.

stride

The number of bytes from the beginning of one scanline to the beginning of the next in a 2-dimensional image.

surface

A two-dimensional area.

ternary raster operation

A raster operation involving 3 input parameters.

VESA

Video Electronics Standards Association.