From: dstamp@watserv1.waterloo.edu (Dave Stampe-Psy+Eng)
Subject: 3D renderer Progress
Date: Tue, 14 Jan 1992 05:21:55 GMT
Message-ID: <1992Jan14.052155.17017@watserv1.waterloo.edu>
Organization: University of Waterloo



Well, the 3D renderer for the 386 or 486 PCs is coming along nicely.
Just finished the C/floating point prototype of the transform/clipping
"front end", and stuck on a simple Z-depth sort and my fast poly
blitter.  Would you believe it, it does 6 fps already on a database 
of 500 polys (2 objects)!  This is on a 486/25, of course, but I
think the assembly/integer version will be 3x faster yet.

Of course, this in not yet a complete renderer.  The scanline
algorithm will eat up a good chunk of execution time and the
drawing to screen will take about the same as now.  But it looks
pretty good.  Still be a few months before the final version is
ready.

Speed gains:  during development of this stage of the prototype,
the biggest speed gain came from swithing from Borlands poly
routines to my own.  Speed went from 1.5 fps to 6 fps.  So if
your renderer is pokey, get a better blitter!  BTW, I found some
problems with the 4-sided poly blitter, but the 3-sided blitter
is just fine, so I used it to emulate.  Drawing speed could easily
be increased 50% by a rewrite of the poly blitter.  Of course, I'm going
for the scanline renderer, so that'll have to wait.

Hope to post a executable demo in a day or so.  Code is kinda blah
right now, but Bernie Roehl is doing some cleanup.  BTW, he's
taking care of the "high end" stuff (object loading, formats, and
database updates) and did the original testing of the transforms
and object-level clipping.


--------------------------------------------------------------------------
| My life is Hardware,                    |                              | 
| my destiny is Software,                 |         Dave Stampe          |
| my CPU is Wetware...                    |                              | 
| Anybody got a SDB I can borrow?         | dstamp@watserv1.uwaterloo.ca |
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