Go here:
http://www.geocities.com/bdchambers79/pov_test/beta11c.html

I thought this scene would be useful for developers, as it demonstrates 
a couple of things.

1) The scene renders much too brightly in version 3.7
2) Speed in 3.7 is abysmal.  3.6 renders it at 800x450 in just under 2 
minutes, and 3.7 takes just over 15.

In both cases, I'm using identical ini-file settings.
The 3.7 version is set to use /threads 4 (I've tried /threads 1, and no 
setting {16 threads default?}, to no avail).  I'm on a Pentium 4 2.8gHz, 
no Hyperthreading support so I don't expect the threading to help too 
much.  However, I would expect the sse2 build to increase performance.

The main problems seem to be the refracting chess pieces, where 
performance slows to a crawl.  I'm going to go out on a limb here, 
because I don't know the internals much, except for what I've read on 
these newsgroups, but here's my guess:

I read previously that 3.7 now implements a document / view model, where 
the render is essentially a view of the document (the scene).  When a 
translucent object is traced, it spawns many more rays which must query 
the scene, thus a large amount of interprocess communication.  In 3.6, 
this isn't a problem.  3.7, however, must spawn messages for each ray, 
creating a huge amount of overhead when many reflective / refractive 
objects are being traced.

Although, I've been wrong many times before, and I wouldn't be surprised 
if I were wrong again right now :)

...Chambers

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