3DLABS Oxygen RPM - Manual (Page 26)

Terms and Definitions
18 3Dlabs Oxygen RPM User’s Guide
Terms and Definitions
AGP: Accelerated Graphics Port.
AGP Sideband Addressing: A method of data transfer where the graphics con-
troller can issue new addresses and requests simultaneously as data continues to
move from previous requests on the main data/address wires.
Alpha Blending: This means to create transparent objects by allowing for the
blending of pixels to simulate the transparency characteristics of an object. With
alpha information, an object can be designed from being totally transparent to
opaque.
Alpha Buffer: A portion of the frame buffer used to define the transparency value
of a pixel in the frame buffer. This data can be used to blend the frame buffer pixel
with the pixel to be drawn to create a composite pixel.
Anti-Aliasing: A technique employed to remove any jagged edges from an object
to appear smooth. This is accomplished by gradually modifying the hue and satu-
ration of pixels.
API: Application Programming Interface. The API translates the instructions
from the application program into device commands that are specific to the
screen’s display controller, the graphics board.
Atmospheric Effects: Effects that mimic fog, rain, snow and smoke by using a
blend function that varies with depth in the scene. Also referred to as Depth Cue-
ing.
BIOS: Basic Input/Output System. A program code in computer memory that
performs the self-test, etc. during system startup.
Bilinear Sampling: A process whereby texture mapping is done through filtering
a group of texels sampled from the texel buffer in 2 dimensions.
Clipping: Removal of elements or sections not contained within the active view-
ing volume.
DAC: Digital to Analog Converter. The DAC converts the digital signals repre-
senting the color values of each pixel to analog voltages suitable for driving the
CRT display.
Depth Cueing: A technique used to give the illusion of depth. With depth cueing,
the part of an object that is farther away is displayed with a lower intensity to give
the effect of depth.