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Gates
03-18-2008, 11:12 AM
I'm running 8.3 on a Mac Pro. Watching it render using Activity Monitor it's clear that while it starts off using 800% CPU it soon falls to 500% and eventually to 100%. Why is that? And can it be controlled?

Chilton
03-18-2008, 11:16 AM
How many render threads do you have, and how many processors?

-Chilton

Weepul
03-18-2008, 03:34 PM
By 8.3 I certainly hope you mean 9.3, since only LW9 has been available natively for Intel Macs.

Are you using the Classic Camera? If so, choose Perspective Camera (or another type), since those types will keep all processors chugging away more efficiently.

Gates
03-19-2008, 06:30 AM
Hi Chilton, I have 8 threads applied.

Weepul, I have a new machine - 2 x 2.8 Quad core, ATI Radeon and GeForce 8800 - but haven't got round to getting L/w 9.?. I'm very impressed by the huge improvement in rendering times from my old machine which was an early G4. I understand that 8.3 isn't native - but I would still like to know whether it can be made to utilise all the computing power available? Would 9.3 really make a significant difference?

Chilton
03-19-2008, 07:02 AM
Hi,

The difference between the Universal Binary and 8.3 would be substantial. Just the improvements in rendering would outperform 8.3, but keep in mind that right now you're running LightWave in emulation.

-Chilton

BeeVee
03-19-2008, 09:11 AM
It wouldn't make any difference if it was native - the Classic camera (LightWave 8.x's camera) has a limitation that means that once a portion of the image allocated to a processor is finished, that processor idles. The cameras introduced with LightWave 9 (Perspective, Advanced et al) do not have this limitation. As soon as a portion is finished the remaining portions are redivided among all the processors.

B

Gates
03-25-2008, 12:27 AM
Hey guys,
Thanks for all that. I'm onto it - no more classics. I've been trying out the Beta version of 9 and the Discovery version too. Does anyone know whether there was a bug in Interpolated Radiosity in the Beta version? :)

Chilton
03-25-2008, 05:56 AM
Ask in the Beta forum

Phil
03-25-2008, 09:06 AM
It wouldn't make any difference if it was native - the Classic camera (LightWave 8.x's camera) has a limitation that means that once a portion of the image allocated to a processor is finished, that processor idles. The cameras introduced with LightWave 9 (Perspective, Advanced et al) do not have this limitation. As soon as a portion is finished the remaining portions are redivided among all the processors.

B

Ah, but there was always the cunning subdivided transparent plate approach. You got your volumetrics rendered at the same time as the rest of the scene as well. Made for very efficient threading if you subdivided enough.

BeeVee
03-25-2008, 09:20 AM
Yes for sure, but a bit tougher to explain... :D

B