ATI Technologies FireGL V7300, User Manual

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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.
Back Buffer
A type of offscreen memory used to provide smooth video and 2D graphics
acceleration. This technique uses two frame buffers, so the process is often
referred to as “double-buffering.” While the contents of one buffer are
displayed, a second buffer, called the “back” buffer, holds the frame being
worked on. In this way, users will only see complete, smooth frames
displayed onscreen.
Bilinear Filtering
This filtering method reduces the blockiness caused when zooming into a
3D surface that is at a right angle to the viewer. A newspaper photo
examined closely enough will show that the picture is made up of tiny dots.
If the photo was enlarged it would start to look “blocky” and less distinct.
This is also a problem for computer-generated images, especially for
surface details.