Presampling Displacement Saving

[jujubee]

I'm not entirely sure what Vray is doing when it goes to Presample Displacement.

I have a file that has a lot of displacement, and it's taking a long time to calculate. When running DR, I wonder if this forces the other computers to also calculate this pass.

Can or is the presample stored anywhere similar to a saved IR or LC map?

[vlado]

The presampling phase for displacement is used to determine a more precise bounding box for the dipsplaced geometry. You can avoid it if you turn off the "Tight bounds" option in the displacement modifier. Especially for cases with more or less regular displacement maps, like grass etc, turning this option off may speed things up.

Best regards,
Vlado

[jujubee]

I turned on tight bounds because I had a stone wall with corners, and where the corners appear there would be a strange gap. Is this problem more solve with continuity instead?

[vlado]

Yep, the "Keep continuity" option should solve this.

Best regards,
Vlado

[plastic_]

The presampling phase for displacement is used to determine a more precise bounding box for the dipsplaced geometry. You can avoid it if you turn off the "Tight bounds" option in the displacement modifier. Especially for cases with more or less regular displacement maps, like grass etc, turning this option off may speed things up.

Best regards,
Vlado

wow, that's important info! this should definitely be in the helpfile...

[jacksc02]

To hijack this thread a little..... I had a dream a while ago that displacement could be calculated and then saved as a proxy file

[vlado]

Yes, it has been requested a number of times; for the time being you can use the 3ds Max Displace modifier for this...

Best regards,
Vlado

[3LP]

I understand that we could use 3dsmax displace modifier for that, but does 3dsmax sample the quad like vray would ?
I though vray would only subdivide the mesh where the displace would be used. Because, with the 3dsmax modifier, or you cut your object in pieces, or you have a object with a lot of subdivides where you don't need it.

isn't it ?

Thanks
Stan

[vlado]

Actually V-Ray will subdivide the object blindly everywhere (the only exception is if the displacement map is perfectly flat over some triangle).

Best regards,
Vlado