ATI Technologies FireGL V7300, User Manual

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Vertex Shader
Three-dimensional objects displayed on a screen are rendered using
polygons, each of which is made up of intersecting triangles. A vertex is a
corner of a triangle where it connects to another triangle, and each vertex
carries a considerable amount of information describing its coordinates in
3D space, as well as its weight, color, texture coordinates, fog, and point
size data. A vertex shader is a graphics processing function that
manipulates these values, producing such things as more realistic lighting
effects, improved complex textures such as hair and fur, and more accurate
surface deformations such as waves rippling in a pool or the stretching and
wrinkling of a character’s clothes as he or she moves.
VGA Connector
A type of graphics connector, sometimes also called an analog connector.
It is the most common type of video connector available, consisting of 15-
pins set in three rows. The “VGA” is an acronym for “Video Graphics
Array,” which is also the name for the video resolution mode of 640x480
pixels, the lowest standard resolution supported by virtually all video cards.
Z-buffer
The portion of video memory that keeps track of which onscreen elements
can be viewed and which are hidden behind other objects. In the case of a
3D image, it keeps track of which elements are occluded by the foreground
in relation to the user’s perspective, or by another 3D object.