Intergraph RealiZm Graphics V25, Руководство пользователя по оборудованию

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Sub-Pixel Accuracy
The Graphics Engine uses sub-pixel accuracy for improving the quality of the graphics image.
Sub-pixel accuracy ensures adjacent polygons and vectors join smoothly.
Window Clipping (Z13, Z25, and V25)
While rendering triangles and vectors, the Graphics Engine discards pixels that would fall
outside the region of the target window. Hardware clipping in this fashion alleviates the
burden of checking objects in software before sending them to the graphics system.
Texture Processor
Texturing is available on RealiZm graphics accelerators that have a texturing accelerator
(Z10) or texture memory (Z13, Z25, and V25) installed. Texturing is the process of applying
a pattern, represented in memory as a two-dimensional array of image color values, to the
surface of a 3D graphical object. For example, a wood grain pattern can be texture-mapped to
the surface of an object, such as a desk, to enhance realism of the image.
Another example of texture mapping is draping a land image from a satellite over a digital
terrain model to create a 3D representation. The Texture Processor module of the RealiZm
graphics accelerators provides a dramatic performance increase for advanced texture
processing when compared with software algorithms alone.
Advanced Texture Processor Hardware
The Texture Processor has its own ASICs on the Z10, and is integrated into the Graphics
Engine/Texture Processor ASIC on the Z13, Z25, and the V25. It supports 32-bit textures,
one byte for each of the color components: red, green, blue, and alpha.
Texture Memory
Texture memory is 8 MB in a Z10 with the hardware texture option, providing up to 2
MTexels of texture maps. If installed in a Z13 or Z25, texture memory ranges in size from 4
MB to 64 MB, providing from 1 MTexels to 16 MTexels of texture maps. If installed in V25,
texture memory ranges in size from 16 MB to 64 MB, providing from 4 MTexels to 16
MTexels of texture maps.