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Old 04-10-12, 09:45 PM   #7
suburbanguy
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Join Date: Aug 2002
Posts: 155
Default Re: SEGA's unreleased 'Saturn 2' and The Dreamcast Story

Here's an interesting USENET post from 1996 about Lockheed Real3D/100 and 3DFX Voodoo Graphics:

http://groups.google.com/group/comp....e=source&hl=en

Quote:
First, let me start off by saying I am going to be buying a Voodoo card.
For low end comsumer grade flight sims and such, the Voodoo looks like
about the best thing available. Second, I am not necessarily responding
to just you, because there seems to be a hell of a lot of confusion
about Lockheed Martin's graphics accelerators. I have been seeing posts
all over the place confusing the R3D/100 with the AGP/INTEL project that
L.M. is working on. The R3D/100 is *NOT* the chipset that is being
developed for the AGP/INTEL partnership.

However, since your inference is that the Voodoo is faster than the
R3D/100, I have to say that you are totally dead wrong. While the specs
say that the Voodoo is *capable* of rendering a higher number of pixels
per second, or the same number of polygons per second as the R3D/100,
the specs fail to mention that these are not real world performance
figures any you probably will not ever see the kind of performance that
3Dfx claims to be able to acheive. This does *not* mean that the Voodoo
is not a good (its great actually) card, just that the game based 3D
accelerator companies (all of them) don't tell you the whole story.


The Voodoo uses a polygon raster processor. This accelerates line and
polygon drawing, rendering, and texture mapping, but does not accelerate
geometry processing (ie vertex transormation like rotate and scale).
Geometry processing on the Voodoo as well as every other consumer (read
game) grade 3D accelerator. Because the cpu must handle the geometry
transforms and such, you will never see anything near what 3Dfx,
Rendition, or any of the other manufacturers claim until cpu's get
significantly faster (by at least an order of magnitude). The 3D
accelerator actually has to wait for the cpu to finish processing before
it can do its thing.


I have yet to see any of the manufacturers post what cpu was plugged
into their accelerator, and what percentage of cpu bandwidth was being
used to produce the numbers that they claim. You can bet that if it was
done on a Pentium 200, that the only task the cpu was handling was
rendering the 3D model that they were benchmarking. For a game,
rendering is only part of the cpu load. The cpu has to handle flight
modelling, enemy AI, environmental variables, weapons modelling, damage
modelling, sound, etc, etc.


The R3D includes both the raster accelerator (see above) and a 100 MFLOP
geometry processing engine. Read that last line again. All geometry
processing data is offloaded from the system cpu and onto the R3D
floating point processor, allowing the cpu to handle more important
tasks. The Voodoo does not have this, and if it were to add a geometry
processor, you would have to more than double the price of the card.


The R3D also allows for up to 8M of texture memory (handled by a
seperate texture processor) which allows not only 24 bit texturemaps
(RGB), but also 32bit maps (RGBA) the additional 8 bits being used for
256 level transparency (Alpha). An addtional 10M can be used for frame
buffer memory, and 5M more for depth buffering.


There are pages and pages of specs on the R3D/100 that show that in the
end, it is a better card than the Voodoo and other consumer and
accelerator cards, but I guess the correct question is, for what? If
the models that are in your scene are fairly low detailed (as almost all
games are - even the real cpu pigs like Back to Bagdhad), then the R3D
would be of little added benefit over something like the Voodoo.
However, when you are doing scenes where the polys are 2x+ times more
than your typical 3D game, the R3D really shines. The R3D is and always
was designed for mid to high end professional type application, where
the R3D/1000 (much much faster than the 100) would be too expensive, or
just plain overkill. I've seen the 1000 and I have to say that it rocks!
I had to wipe the drool from my chin after seeing it at Siggraph (We're
talking military grade simulation equipment there boys, both in
performance and price!)


Now then, as I mentioned before, I'm going be buying the Voodoo for my
home system, where I would be mostly playing games. But, I am looking
at the R3D for use in professional 3D application. More comparible 3D
accelerators would not be Voodoo, Rendition based genre, but more along
the lines of high end GLINT based boards containing Delta geometry
accelerator chips (and I don't mean the low end game base Glint chips,
or even the Permedia for that matter), or possibly the next line from
Symmetric (Glyder series), or Intergraph's new professional accelerator
series.


Ted K.
Shadowbox Graphics
Chicago - where being dead isn't a voting restriction.

Extremely interesting and well written IMHO.
suburbanguy is offline   Reply With Quote