Glossary - ATI Technologies Nexus GA User Manual

D

Glossary

Alpha When an image has an alpha value for each pixel, this tells
blending how much to blend the colors from the image with the
background colors. The lower the alpha values the more
transparent the image looks.
Anti-aliasing Method used to remove the jagginess of an image. When
anti-aliasing is used, the edges of an image appear smooth
and usually somewhat blurry.
Back buffer A type of offscreen memory used to provide smooth
video and 2D graphics acceleration. This technique uses
two frame buffers, often referred to as "double-buffering".
While one buffer is being displayed, a second buffer of the
same size, the "back" buffer, holds the frame being worked
on.
Once a new frame is ready in the back buffer it is copied to
the front buffer - the display screen. In this way, you will
only see complete, smooth frames, and not the operations
performed on them.
In order to increase performance, all memory used for
back buffers are on your ATI graphic accelerator card.
Bilinear When texture mapping is performed an image can become
Filtering very "blocky" or "pixelated" when the texture is viewed
close up. Bilinear filtering samples four texture pixels,
takes the weighted average of these pixels and applies the
average of these "texels". This blended color is used to
provide a smoother looking texture.
Bitmap A bitmap is a graphics or character representation
composed of individual pixels, arranged horizontally in
rows. A monochrome bitmap uses one bit per pixel (bpp).
Color bitmaps may use up to 32-bpp, depending on the
number of colors desired.
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