ATI Technologies RADEON 8500 MAC EDITION, Руководство пользователя

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Glossary
Alpha blending When an image has an alpha value for each pixel, this
tells 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 graphics accelerator card.
Bilinear Filtering When texture mapping is performed an image can
become 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.
Buffers Your ATI accelerator card includes on-board memory
which is used in a number of ways. Buffers are portions
of this memory used as temporary storage on your card.
One large buffer is always used to display the screen you
see; this is the “display buffer”. The rest of offscreen
memory is used by applications as back buffers,
z-buffers, and texture buffers.
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