Vray Multiscatter issues

[Alyosha]

Ok cool, I'm glad you got it working:-)

[Tommy L]

I simply cannot believe that normal maps crash Max is used in Multiscatter. But its true. Its taken me 3 days to find this thread and figure it out.

[icube]

I simply cannot believe that normal maps crash Max is used in Multiscatter. But its true. Its taken me 3 days to find this thread and figure it out.

 

its documented in the official manual http://docs.rendering.ru/en:multiscatter#crashing )

[clauco]

Many hours spent to find why causes 3dsmax to crash using vray and multiscatter. I verified to don´t have normal maps into my scene materials, try to have vraymaterials applied to every object, but it continues crashing. Most of the times when calculating LC, but in few cases when rendering process finishes.

 

Somewhere I read about of issues when trying to scatter groups. That´s not my case, usually I scatter only vraymeshes but max continues crashing. Checking memory consumption from task manager panels everything seems to be ok, memory used is a half of what is available. Another curious thing is if I override overall scene materials with a color in Vray global switches panels, everything works fine, but if I back to objects materials problems arise.

 

For some reason I decided to break hierarchies (groups and warps,usually) into my scene, but keeping settings and objects. After that, issues dissapears and troubles seems to be solved.

 

Does anyone else experienced this? I mean, even having groups into the scene (not for being scatered) max crashes when using multiscatter.

 

I´m not really sure about my practice efficiency, It works for me, so I encourage to try this and would like to read about your results.

[icube]

here are some ideas for troubleshooting:

 

1. Check your objects and materials for any problems.

Basically speaking, it may render fine with small CPU or RAM errors, which may be unnoticed when rendering a single object,

but when you multiply it thousands or millions times with MultiScatter that problem will just grow exponentially and crush the system

 

2. Try not to use LC.

Light Cache is very fast algorithm, but there are some drawbacks. Light Cache needs much more RAM than other V-Ray GI algorithms. MultiScatter is a tool for creating huge amount of geometries which also needs RAM.

therefore there is a big chance to encounter problems (very slow rendering or crashing) when you use LC with MultiScatter.

 

So using Light Cache in exterior visualisation consumes lots of memory wherever you are using MultiScatter or not,

and its just our very general recommendation not to use it, unless you really know what you are doing and have tons of memory.

 

3. Don't use groups.

as MultiScatter support only geometries, but groups may include other non-supported objects

 

4. Check rendering settings.

MultiScatter itself is a very solid plugin but it generates lots of geometries, which pushes VRay, 3ds Max and the hardware to its limits, so optimisation is required in all parts of the process

advanced knowledge of VRay is also essential, especially for exterior visualization

 

in case you still cannot find the cause of the problem, please send us the file to troubleshoot

please also make sure you are using latest version 1.2.0.12