VrayRT-GPU on displacement (Material Editor) uses ALL RAM and freezes.

[ramon_perez]

I'm not a big fan myself of 3dsmax displacement on the material editor, however, many scenes I work with use it moderately on their Material Editor displacement map. (ie. tree barks / tiles / etc)

Whenever I hit render on a scene which has somewhere a material using displacement, the 'compiling geometry' process eats all up of my available 64Gbs of RAM and just freezes there doing nothing. (Even though the scene could use only 5Gb)

So now everytime I import a scene I have to make sure to check EVERY material of EVERY object to make sure there are no displacement values/maps to avoid this problem. Which is a painful process..

Is this a known issue or is there a solution for this issue coming soon? Any help would be great,

Note: This is NOT the case with Vray displacement modifier)

Thx!

[yavor.rubenov]

Hello,

Material displacement uses the settings in the Default displacement rollup (in the System tab if your production render is Adv). If the "Edge length" parameter there is very low you could get very high RAM consumption. With the default setting of 4 px in my test the RAM usage was less than 1Gb but if I use 0.1px then RAM usage went above 20 Gb.

Could you check your settings or you send us a scene and we can check ?

Best regards,
Yavor

[ramon_perez]

Thanks Yavor,

I have checked settings and they are all set to the default values in the displacement tab. Which email address should I send the scene to? Thanks.

[yavor.rubenov]

You can send it to our support (support at chaosgroup.com) - they'll check the scene and forward it to me.

Best regards,
Yavor

[ramon_perez]

Hello, I went ahead and troubleshoot the scene to the object that's causing the issue and I think the problem is the following:

The Material with disp. map applied is part of a multi sub-object material. When displacement map is activated, the ENTIRE object gets displacement. ie. A tree with displacement in TRUNK material only, but leafs and branches also get displaced!

Please let me know if this is an known issue within RT-GPU and if there's a solution for it,

Thanks.

[yavor.rubenov]

Yes it's a know issue - displacement in part of a multi sub object material is indeed applied to the whole object in RT. Unfortunately it is not fixed yet. I'll give bump to the priority of this issue in our system.