After a little experimenting I found that it was simply that Windows 2000
was sharing the pvengine process across both processors, so that it could
load balance other processes better.  The affinity by default is set on CPU0
+ CPU1, even if the process only contains a single thread.  As more
processes are set to a specific processor, it throttles the other processes
more towards the opposite processor to ensure they're being balanced in
terms of cycles.  I tried forcing pvengine to affinity CPU0, and it does
take up 100-99% of that processor, so the thread is getting the equivilant
of 100% of a processor's time.  As soon as it's switched back to CPU0 + CPU1
it balances again.

The process shows as taking up 50% of the total CPU usage, which is correct.
(graph of the cycles from switch affinty from CPU0 to CPU0 + CPU1 included
just for fun ;)  Even with distributed.net running it still gets 50-49% of
the total usage, while distributed.net is throttled to the other processor,
and gets the remaining 49-50%.  Works well :)

Anyway, that's getting really off-topic (kinda), so back to the image.

I tried raising the jitter from 0.3 to 1 as was suggested by Nathan and it
made the image look a lot better, but it was getting dark and light patches,
so I figured it still needed more photons.  I bumped the count up to 3
million from 2 million, but it was still patchy, so I went to 4 million,
then 5 and then 6 million (heh) and it seems to have smoothed it out a fair
bit.  I probably should read the documentation a little more carefully...
maybe there's an option I've missed to help a little bit, but then again
maybe there isn't (I guess that's what jitter is for really), so I'm happy
with pushing the count up.  It's still a little patchy in some of the more
sparse areas of the shadows, but no where near as bad as it was :)

I've also replaced the standard light with an area light and it looks a lot
better (I'm a big fan of soft shadows, heh) but there is an atefact I've
having difficulties getting rid of (the harsh edge to the shadows that
appears on the shadows of the first and second torii on the left side of the
image, just where it goes really soft).  Any ideas how to get rid of it?  I
tried using 32x32 lights in the area light too (instead of the 18x18 in that
image) but it was still there :/

Anyway, I can see I'm going to have a LOT of fun with photons and radiosity!

Lance.

thezone.firewave.com.au
www.firewave.com.au

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