ATI Technologies RADEON X1900 G5, User Manual

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AGP
The Accelerated Graphics Port (AGP) is a slot on the computer
motherboard designed specifically for 3D graphics cards. AGP runs 3D
images much more smoothly and quickly than was previously possible with
PCI video cards; AGP runs at several times the bus speed of PCI and
employs sideband addressing, so multiple data transfers between the
graphics processor and the computer can take place concurrently. AGP is
currently being phased out in favor of PCI Express® (PCIe™).
Alpha Blending
Alpha blending is used in 3D graphics to create transparent or opaque
effects for surfaces such as glass and water. Alpha is a transparency value,
so the lower the value, the more transparent the image looks. It is also used
in animations to produce such things as fading effects, where one image
gradually fades into another.
Anisotropic Filtering
A technique that preserves the surface details of an object as it recedes into
the distance by utilizing and blending together the object’s texture maps.
This makes 3D objects appear more realistic as the detail of their surface
texture is retained in a smooth, seamless fashion on the sections that move
or fade away into the background.
Anti-aliasing
A method that smooths out the jagged edges of a curved object. A black
curved line on a white background displayed on a computer screen will
have some jaggedness along its edges due to the inherent limitations of
using discrete pixels to display the image. Anti-aliasing smooths out this
jaggedness by filling in the white spaces between the jagged edges with
varying shades of grey.
Aspect Ratio
The proportions of a display are expressed as a ratio of its width and height.
Common ratios include 4:3 for TVs and CRTs, 5:4 for LCDs, and 16:9 for
widescreen displays.