3dsMax Vray Displacement Help

[TomD_Arch]

So I'm new to Vray as of this year. I'm having a hard time with displacement in Vray and the VrayDisplacementMod. Any time I try to use it it seems to eat-up memory calculating geometry or resolving light cache and never even gets to start rendering. I've been reading everything I can find, but seems to fully explain the theory behind how you optimize your displacement setting for the rendering. I've been to Chaos Group and read through the online vray manual without much more understanding. With all this emphasis on PBM materials and the use of displacement, I feel like I am missing something and would love a bit of help.

[Nicolai Bongard]

I think this should cover most if not all of your questions related to displacement in vray.

Give it a go, and if you still do not get displacement to work you should perhaps try posting some of your displacement and render settings.

https://docs.chaosgroup.com/display/VRAY3MAX/Displacement+Modifier+%7C+VRayDisplacementMod

[Francisco Penaloza]

As rule of thumb, I try to go brute force when I have to us displacement. I usually use brute force first bounce and light cache for second, but Light cache is not displacement friendly, both of them fight for RAM

Having said that, try to use 2D displacement as much as you can, I know sometimes it won't apply but this is easy on memory.

Also a well subdivided geometry also help displacement, other than that follow the guide that Nicolai posted.

[Tom Sproule]

Yes, I would agree with Francisco.

 

I would suggest you do a test and figure out your settings. I use displacement fairly frequently now. The way I came to grips with it was creating a simple scene with a plane, a light and a camera. I put a brick material on the plane with displacement. I opened task manager and watched to see how much memory it was eating. Then I put a subdivide modifier on the plane, under the VrayDisplacement Mod and tried rendering again and again to see how much of a difference the change in subdivide did to how much memory displacement was eating.

 

Unless we're working on a massive scene or we're using fog in the scene we always work in mm. I've found that normally about 200 on the subdivide - that's subdividing it into 200mm geometric faces, normally works great with most scenes when I use displacement.

 

Hope this helps.

 

Best, Tom

[TomD_Arch]

That subdividing my Geometry did the trick. I had 4 30' tall 2'x3' masonry columns I was using Vizpark walls & Tiles to texture. when I added the displacement I couldn't even get the rendering to finich light caching on my farm. The columns were all simple rectangular poly geometry. I went back into teh box and started adding more edges 70 along the 30', 10 along the 2' and 14 along the 3' (all were just guess's at a first attempt). Bam! the thing rendering with beautiful displacement and it only took about 20 minutes longer then the original 3 hour render for 4800x 3200 resolution.

 

This is the first time I've read anyone mentioning needing to subdivide the geometry itself. I kept think when subdivide was brought up it was in reference to the Max Subdivs number in the displacement setting.

 

Thanks everyone!