Maxwell Render

Hello, me again!!

I'm trying to render a stack of 15 speakers for a client. One speaker (80,000 triangles) renders fine and they are all identical, so I thought I'd use Softimage instances (although I have had problems with instances in Maxwell before). I'm rendering at a pretty high res (2048 x 3072) and the error comes in a variety of ways;

- sometimes when I hit render in Softimage the mxs export runs and then Maxwell comes up with an 'encountered an error and needs to close' window immediately
- sometimes if, after this error, you try again the rendering starts and then I get an 'encountered an error and needs to close' windows at a certain sample level; maybe 6, 7 or even 10 - I'm trying to get to 12.
- if I use duplicates instead of instances in Softimage, the mxs exporter fails at about 25% and never even launches Maxwell

There's plenty of RAM; I've got 6GB and Maxwell only seems to be using 500MB (when using instances) in task manager. I'm using Softimage 2010 SP1 (64bit) and Maxwell 2.0.1.0 64bit under Windows XP 64bit SP2.

Any ideas?

_________________
oz.

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Any chance you could send me the scene, or a simplified version of it? Confidentiality is guaranteed, of course.

Mihnea,

thanks for offering to help with this, sorry I didn't get straight back to you yesterday - I got caught up with another project.

The zipped files are 11MB so I've uploaded them to MegaUpload and the link is; (it should be live for about 7 days)

<link sent via pm>

This is a Softimage 2010 SP1 project with all the sub directories. I've included all the materials and pictures, the only extra materials used are some Maxwell 1.7 mxm's that are from the standard install directory.

I've included two scene files;

15subs_04_180110.scn which just has the hanging frame and the top speaker - this seems to render fine.
&
15subs_04_180110_inst.scn which has the hanging frame, the top speaker and 14 instances - this is where the problems are. When I just did a test render it got to sl 5 and then crashed!

I was going to include the duplicate version (which crashes during the Softimage mxs export process) but is was 94MB! This scene can be easily created by taking the single speaker scene above, branch selecting (middle click) the MLA-SUB model and going to the Edit button (bottom right) and selecting Duplicate Multiple; 14 copies with transforms of (-0.6082) in the Y direction.

Thanks again for looking into this for me, let me know if you need anything else?

It would be great if you could resolve this for me as this client has asked for a 24 speaker stack as well!

Cheers,

Richard.

_________________
oz.

"Make lunch, not war."

Visit http://www.3D-Visualist.com/
for all things 3D, especially XSI.

Thanks for the scene and the details, I'll let you know as soon as we figure it out.

Thanks, keep me posted...

_________________
oz.

"Make lunch, not war."

Visit http://www.3D-Visualist.com/
for all things 3D, especially XSI.

Mihnea,

I've just had an idea; there are some emitters in my model (the orange logos are LEDs) and I seem to remember that you can't instance emitters?

Having said that, I've just successfully rendered a smaller stack of 6 speakers (one model and five instances) for the client as a interim render and it got to sl 12 absolutely fine - no errors!?

_________________
oz.

"Make lunch, not war."

Visit http://www.3D-Visualist.com/
for all things 3D, especially XSI.

The crash when using duplicates is caused by a "feature" in the XSI SDK which I wasn't aware of (it might have been introduced in 2010, or maybe we were just lucky and never ran into it until now). I've fixed the problem and we'll release an update as soon as possible. However, even after the fix, exporting the scene with duplicates is not feasible; due to a limitation in the Maxwell SDK, the plug-in would require around 12 GB of RAM to write the scene with 15 speakers. It works if your page file is large enough, but it becomes extremely slow once it starts swapping to disk (unless of course you have a machine with 12 GB of memory).

I tried reproducing the crash with instances, but I don't have all the materials you referenced from the Maxwell DB. Could you please export the MXS with instances on your computer, use Studio's pack'n'go to collect the dependencies, compress everything and send me the archive? RAR or 7z should get the size down to a manageable level, but if it's still too large we can arrange for some FTP space.

Thanks again.

PS: as far as I know, instanced emitters simply don't work, they shouldn't cause crashes, but I might be wrong.

What was the 'feature', or is a techy SDK issue?

Wow, 12GB! Is this due to the complexity of the mesh? Each speaker is only 80,000 tris and the whole dupe scene was only 1.2million. Or is there some other factors involved?

I'll pack'n'go the instanced scene today, thanks.

As far as instanced emitters go, this may have something to do with it. I'm working on another scene for this client and forgot about not instancing emitters and, sure enough, the Render crashed half way through. After a flash of inspiration and stripping out only the emitters from the instances and duplicating them instead, the scene now renders fine.

_________________
oz.

"Make lunch, not war."

Visit http://www.3D-Visualist.com/
for all things 3D, especially XSI.

XSI's string object was freeing its internal memory at a time when I wasn't expecting it. I was using the freed memory, which now contained garbage, so the plug-in crashed. That's the technical explanation, I don't know if it helps. :)



There's something really weird going on here. Initially I thought your mesh is very dense, but I checked now and that's not the reason. Hopefully it's my mistake so I can fix it for the next patch.



I got the scene, thanks. I'm rendering it now and it reached SL 8 without crashing. I'm using a newer Maxwell build than what's publicly available, so it might be that the bug is already fixed for the next patch. I don't know when that patch will be, though. :) I'll keep testing the scene and I'll also try with the public build.

Anyway, once I fix the memory issue on export, you will be able to use duplicates even for 24 speakers, so you won't have to wait for the Maxwell patch to render the scene (the plug-in patch will most likely be ready sooner).

PS: to see instances in Studio you have to select the original object first; I guess that's why you couldn't see them when you did the pack'n'go.

Update: I rendered it again and this time Maxwell crashed, I'll forward it to the people who can fix this.

Re: update. Yes, it seems to be a bit random. Sometimes it renders to sl5, sometimes sl8 but I could never get it to sl12.

However...

I have revisited the scene; stripped out all the emitting objects and put them in a separate model, instanced the speakers (with no emitters) 14 times and then duplicated the new model containing the emitters (also 14 times). This time is worked! It got to sl12, which is what I wanted.

So it does, in fact, look like it was the instanced emitters that were causing the problems. However that doesn't quite explain why the render seems to crash at a random time (although always at an integer sample level; 5, 7, 8, 10). I would have thought that, if instancing emitters doesn't work the scene wouldn't have rendered at all?

Having said all that, it looks like you've found a couple of bugs within the XSI's plugin so I think it's been a worthwhile 'adventure'!

Thanks for looking at this for me and I look forward to seeing the updated XSI plugin...

Cheers,

Richard.

P.S. the techy explanation didn't really help, I'm afraid, but thanks for sharing this with me!

_________________
oz.

"Make lunch, not war."

Visit http://www.3D-Visualist.com/
for all things 3D, especially XSI.

Ok, the memory problem was my fault. The plug-in had a bug which caused it to create one material for each object, instead of recognizing materials shared between objects. The Maxwell SDK needs quite a bit of memory for each material and I was trying to make 2000 separate materials for the scene with 15 speakers. I'm not sure when this bug was introduced (it wasn't always like this, of course), but it's fixed now and we'll release an update as soon as possible.

Great to hear you've found the bug and know how to fix it, thanks for the imminently updated plugin.

In the meantime, stripping out all the emitters from the models and then instancing the non-illuminating parts and duplicating the emitting parts seems to be working - I've run two successful render today without crashing!

_________________
oz.

"Make lunch, not war."

Visit http://www.3D-Visualist.com/
for all things 3D, especially XSI.

Mihnea,

thanks for releasing the 2.0.2 update for the Softimage plugin, I'll give it a spin and let you know how it goes...

_________________
oz.

"Make lunch, not war."

Visit http://www.3D-Visualist.com/
for all things 3D, especially XSI.