#Sparks
Eric,
As a neutral voice in terms of speed claims, and someone familiar with the
raptor (I built the Screamer prototype unvailed at SigGraph) I would like to
make the following points on speed:
The speed increase seen will depend HEAVILY on the scene content.
The raptor can be slower than the amiga, due to fixed overhead, but only for
very easy scenes. For example, a scene that renders in 20 seconds on an Amiga
might render in 1 or 2 seconds on a raptor, but include 60 seconds or more of
file transfer.
The processers doing the rendering are fundamentaly different (040 vs r4400).
This is IMPORTANT to speed claims. The big advantage of the 4400 (other than
generally being faster) is its pipelined FPU. The 040 as you may recall has a
limited FPU and requires software libraries to do most of the higher functions
(sin, tan, etc..) while the R4400 does all this in hardware. This means that
for certian types of images that are FPU intensive (it also helps if most of
the rendering code fits in the cache of the 4400).
I did most of my work with these things using two processors of the older (and
slower) deskstation machines. Results varied from perceptually quite a bit
faster to way,way,way faster, as long as the scene was sufficiently complex
(i.e. more than a few min rendering time). Based on my experience, the 10x
stock amiga 4000-040 is the 'typical' number. Very few things will go any
slower than this at all, and certian classes of scenes will go MUCH faster.
All of this indicates it is very difficult to determine reletive speed between
architecurally different machines, even if they are running the same
application.
To wrap up, from everyone I know doing 3D graphics for $, the Raptor is a very
effective, revenue enhancing tool. You certianly don't have to buy one (it is
a free country). Deskstation, however, does seem to make the fastest R4400
based NT machines around, and as I understand, does a good job of installing
the ScreamerNet software and making things work out of the box (not a trivial
task with an NT machine, as I know).
Charles