[rescue] FS/FTGH: Sun kit

Richard legalize at xmission.com
Mon Jan 16 23:31:57 CST 2006


In article <200601170429.XAA01897 at Sparkle.Rodents.Montreal.QC.CA>,
    der Mouse <mouse at Rodents.Montreal.QC.CA>  writes:

> [...]  Knowing how to use the transform
> engine in the cg6 would have helped considerably, even though the
> colour capabilities were not at issue  [...]

Umm.... just because something has registers labelled X, Y, and Z is
no reason to infer that it has a "transform engine", if by that term
you mean the ability to apply 4x4 coordinate matrices to points.  In
fact, existence of a transform engine would be more implied by the
presence of a W register more than a Z register, since vertices are
customarily structured as homogeneous points and pumped through a 4x4
transformation matrix.

For instance, the pixel processor chip in Evans & Sutherland's ESV
workstation (a machine from 1989, so its comparable technology to the
cg6) has low-level commands that accept X, Y, and Z triplets for
rasterization of lines and points.  However, there is no transform
engine in the pixel processor chip -- its just a rasterizer.  Vertex
transformation was handled by an array of AT&T DSP32C chips, anywhere
from 4 to 44 of these chips would be operating in parallel, depending
on the model number of your ESV.  (An ESV/3 has 4; an ESV/50 has 44.)
-- 
"The Direct3D Graphics Pipeline"-- code samples, sample chapter, FAQ:
          <http://www.xmission.com/~legalize/book/>
             Pilgrimage: Utah's annual demoparty
                <http://pilgrimage.scene.org>



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