ProOptimizer causes .vrscene file to balloon in size massively

[Joelaff]

I have a scene with a bunch of condensation on bottles. When I export a vrscene for rendering in Standalone the vrscene file is about 120MB.

I added a Pro Optimizer to each of 9 EditMesh objects for the various condensation droplets. After I applied the Pro Optimizers (and thus LOWERED the poly count) the next time I exported the vrscene file it ballooned to 7GB !

Any thoughts on how to avoid this? In this case I left the Pro Optimizer as a modifier. I guess I will try collapsing.

I went back and disabled the modifiers and the vrscene file went back to the smaller size.

Thoughts on why this would happen? I would think the vrscene export would just write the final mesh from the top of the modeling stack, but something is definitely weird here.

Max 2023, VRay 6.1 nightly form Apr 18, 2023

Thanks.

[vladimir_krastev]

Hi, thanks for posting. Just tested this in 3ds Max 2023.3 and V-Ray 6.10.06 and the files are the same size. No collapsing.
The scene is too big to upload directly but you can test the same easily. I used a car from Cosmos and imported the proxy as mesh and went from there.

[Joelaff]

Weird. I definitely got a 7GB+ vrscene file with the pro optimizers ON, and then a ~100MB vrscene file with them off. My objects were EditMesh before the optimizers if that makes a difference.

[Joelaff]

I will see if I can get it to happen with one of the object in a scene by itself, and then send.

[Joelaff]

I have a test scene ready to send to support, but I wanted to make sure you were testing with an animation range set in the output of the vrscene. FWIW I have 1002-1126 set (even though these objects actually have no animation at all).

[Joelaff]

I sent a link to the simpler scene to support (client NDA stuff)

Ticket # 108316


Below is the info I sent in the support ticket as well:

If you export a vrscene of this scene you get a very large vrscene file.
If you turn off the ProOptimizer modifiers in each object the vrscene is
small again.

** Please note you need to export an animation to the vrscene. I
specifically have the frame range set to 1002-1126 in the vrscene exporter
(or if I use Deadline's vrscene exporter the same thing happens).

Also note that if you for some reason do NOT get a giant vrscene file with
the ProOptimizers enabled delete those modifiers and re-create them (using
the same settings, which are 35% for the first object and 50% for the
other two).

Max 2023.3, Win10, VRay Build 32029 nightly

Thanks.

[vladimir_krastev]

Hi, I haven't tested animation, just a static model. I will have a look at your scene and get back to the thread.

[Joelaff]

Thanks. Much of the sized is the the geometry, and having to write it as ASCII (7bit I guess, or 8 at the most), but in this case the ProOptimizer made a giant difference. I am guessing that the object was somehow seen as animated, but I am not sure. I did notice that some parent objects had visibility animated (and inherit visibility was on). It wasn't actually animated. It just had a bunch of 1.0 keyframes due to some export from Maya. I deleted those, but I don't think it solved the issue.

[Joelaff]

I discovered something else, which may be the root of the evil. Adding objects (dense meshes) to a Multimatte Element by selecting them in the include box (Red include/exclude, G, B) makes the file size grow massively! (The massively part I think was from adding multiple tylfow derived objects, which may be being treated as animated and are stopred frame for frame perhaps?? But either way it is definitely duplicating mesh data for MultiMattes, and possibly ExtraTex)

Why would adding Multimattes copy the actual mesh data? Can't it just reference the existing node already included in the vrscene?

In fact, it seems to even increased the size when you include meshes or tyflows that are not even able to render!

[vladimir_krastev]

Hi, I tested the ProOptimiser in a simple scene and file size increases in a similar fashion if we export animation. In general the vrscene exports the differences from frame to frame and this adds up to the file size.
So in this case it seems to store the model with ProOptimizer for each frame. For instance if we have animated Bend modifier it is the same but at least we have a change in the model from frame to frame. Let me dig a bit more into this and I will get back to the thread.

[vladimir_krastev]

The final outcome is an issue with the ProOptimizer itself and I am sorry to say we can not help with that. I tested the Optimizer modifier though and it is not causing these issues. If you can please use the Optimizer modifier instead and it should be fine.

[Joelaff]

So the ProOptimizer is telling max that the data changes every frame? And thus it gets re written for every frame even though it is not actually changing?

Could you folks pass this on to Autodesk so perhaps they would fix that? They are more likely to listen to you

The MultimatteElement thing is definitely a VRay issue, though. This occurs with or without ProOptimizers.

[vladimir_krastev]

Adding objects (dense meshes) to a Multimatte Element by selecting them in the include box (Red include/exclude, G, B) makes the file size grow massively!

Hi, I was not able to reproduce this behaviour. File size of the exported vrscene stays the same with or without MultiMatteElement. Please send us a scene that reproduces the issue trough your ticket.

[Joelaff]

Let me see if I can find that. I think it depends on using all the multimatte channels and only happens if you use Include/Exclude.