PDA

View Full Version : Procedurals changing between computers



Lude
08-04-2008, 03:31 AM
Is there a way to stop procedural textures changing in appearance when rendering on multiple computers.

Iím rendering a scene on 3 computers all with the same motherboard and CPU but one of them has a different GPU from the rest. Could that cause a procedural texture to be different on it compared to the other two computers?

This is getting quite annoying now, so any help is appreciated.
Lude.

zardoz
08-04-2008, 04:21 AM
well I didn't know that that could happen. What I suggest is to create uvmaps and bake the procedural.

Lude
08-04-2008, 04:24 AM
Ok I did a test, I'm not using screamernet by the way.

All 3 computers rendered the procedural textures differently.

Is this also problem when using a proper network rendering setup?

Lightwolf
08-04-2008, 04:25 AM
I’m rendering a scene on 3 computers all with the same motherboard and CPU but one of them has a different GPU from the rest. Could that cause a procedural texture to be different on it compared to the other two computers?

A different GPU? No, not really, the GPU isn't involved in rendering at all. Which prodcedural is it?

Do all machines use exactly the same plugins?

Cheers,
Mike

Lude
08-04-2008, 04:51 AM
Iím using Puffy Clouds, but this isnít the first time Iíve seen this, it happens with the sort of procedurals you would use all the time.

The scene has no fancy plug-ins itís all bog standard LW 9.2 but itís been happening for years in 7 and 8 and Iím rendering in FPrime 3.2 on all computers.

Up until now it thought it was caused be different computer specs but these 3 Iím using now a very close only difference is 2 have 8800 GTXís and the other an ATI card.

Hereís a gif to show the changes.

Lude
08-04-2008, 04:52 AM
Ignore the crap colours and youíll get the idea.

Lude
08-04-2008, 05:29 AM
I don't think this is an FPrime problem, I tested it in the LW native render and it's the same.

Lightwolf
08-04-2008, 05:39 AM
I don't think this is an FPrime problem, I tested it in the LW native render and it's the same.
If it's the same CPU and the same procedural it should lead to identical renders. I suggest you submit a bug report.

Cheers,
Mike

Lude
08-04-2008, 04:10 PM
So I was thinking about this a bit more, the computers that I'm using all have the same CPU but they have been overclocked and because there ram is not all the same I think they have slightly different settings in there bios.

Could this be whatís causing them to render deferent from each other.

Iím wondering if anyone has list of what needs to match exactly between computers to get matching renders.

Lude
08-04-2008, 04:13 PM
Also I was wondering is this also a problem when using screamernet. Is it able to use computers with differing specs?

Lightwolf
08-04-2008, 04:15 PM
Could this be what’s causing them to render deferent from each other.

Maybe the overclocking, depending on how extreme it is.
What if you try running all at the original clock speed for a test?

I’m wondering if anyone has list of what needs to match exactly between computers to get matching renders.
I've got matched renders on extremely mixed farms (i.e. AMD, intel, anything from a P4 to an Athlon, Athlon64, Core2 Duo and Quad). But I don't use that many different procedurals either.

Cheers,
Mike

Lightwolf
08-04-2008, 04:15 PM
Also I was wondering is this also a problem when using screamernet. Is it able to use computers with differing specs?
Yup, no problem. And 9.5 will make that a bit easier as well.

Cheers,
Mike

shrox
08-04-2008, 06:30 PM
Does overclocking affect the "speed" of something like turbulence procedural, or the movement of a texture on an axis?

Hopper
08-04-2008, 06:36 PM
Well .. it IS a procedural after all. Does this procedural create it's base from a random number seed off the clock perhaps?

And I'm not asking this to be a smart *** ... I'm asking because I don't know, but it would seem to make sense.

Lightwolf
08-05-2008, 01:17 AM
Does overclocking affect the "speed" of something like turbulence procedural, or the movement of a texture on an axis?
No, but it could affect the accuracy of the calculations on the CPU. After all, you are running it out of spec...

Cheers,
Mike

Lightwolf
08-05-2008, 01:18 AM
Well .. it IS a procedural after all. Does this procedural create it's base from a random number seed off the clock perhaps?

Only if it is a badly coded CG procedural. It shouldn't.... but that doesn't mean that it doesn't either ;)

Cheers,
Mike

JBT27
08-05-2008, 02:58 AM
Just to confirm also that on our six machines, all P4s but ranging over about five years, we have never seen this variance in procedurals rendering.....but then we don't overclock either.

Julian.