Path: chuka.playstation.co.uk!scea!greg_labrec@interactive.sony.com
From: Ed Federmeyer <fedeedw@charlie.cns.iit.edu>
Newsgroups: scea.yaroze.programming.3d_graphics
Subject: How fast is fast?
Date: Tue, 24 Jun 1997 23:28:52 -0500
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I took the 'morph' demo and started messing around with it.

Basically, I removed the "morph" function so that the image remains a
flat picture made up of many polygons.  My version doesn't 'morph' to
the cylinder/sphere/etc.

Then, I removed the 'flat.h', 'sphere.h', and other .h datafiles, and
instead generate the vertices of the polygons at runtime, so that I can
#define the number of polygons and recompile, without needing to regen
the datafile.

Then I started experimenting with breaking the TMD into different
numbers of polygons.

What I found was that I was able to get about 53K polygons per sec. 
Much more than than and my framerate dropped.

I've read specs that say the PSX is capable of up to "360K shaded &
textured polygons per sec."  (Data from the Next Generation Online web
site in particular).

This is about 6x slower than the theoretical limit!  The main loop only
does the minimum setup for the matrices, translates the TMD object, and
displays it.  (Look at the main.c from morph, and just remove the
references to "state" and all that "changeTo" stuff).  The only code
that is running are the Yaroze librares operating on a TMD and
displaying it.

Any ideas how much faster I can expect to get with the Yaroze libraries?

Are the profession libs faster just be thier very nature (ie, the pro's
don't use TMDs, they use XXXs, which is faster???)

Do the pro's get thier speed by scrapping the libs completely and
directly programming the GTE/GPU?  I guess I'm wondering how close
Yaroze programming really is to professional PSX programming-  do the
commercial PSX games really use the Gs routines us Yaroze guys
know-and-love?

Thanks for any insights,
Ed Federmeyer