vray displacement pulls apart edges on my box

[stayinwonderland]

hi,

 

got a box of water that i want to see all the way around, it has a vray displace modifier for the suface ripples but the displace opens up the edges so you can see through the gaps. Looks pretty ugly.

 

I can't for the life of me figure out how to stop this. I tried shrinking the UVW of the modifier stack and thought if i stopped it from tiling, the displace would terminate a few units short of the edge. Also thought I could make a mask material and fade out the displace towards the edges but this too didn't work.

 

Ideas?

[RyderSK]

hi,

 

got a box of water that i want to see all the way around, it has a vray displace modifier for the suface ripples but the displace opens up the edges so you can see through the gaps. Looks pretty ugly.

 

I can't for the life of me figure out how to stop this. I tried shrinking the UVW of the modifier stack and thought if i stopped it from tiling, the displace would terminate a few units short of the edge. Also thought I could make a mask material and fade out the displace towards the edges but this too didn't work.

 

Ideas?

 

That's what the 2D version of displacement does, hence the surname "for surfaces".

 

But it's fine for volume usages, but you have to up the precision, from default 8 (which is ok for a bit wavy ground) to 32 or even 64, try until you're satisfied.

 

Another thing to do but with above as well, is to use "shift" so the the displace doesn't blow up so much. Use negative value, and bring the displacement back .

[stayinwonderland]

hmm, curious. I tried that and it's till breaking up the edges. Any ideas?

 

UPDATE:

 

Found this: http://www.spot3d.com/vray/help/150SP1/examples_displacement.htm#ex9

 

I think it's 'keep continuity'.

 

"Keep continuity - using this will try to produce a connected surface, without splits, when you have faces from different smoothing groups and/or material IDs. Note that using material IDs is not a very good way to combine displacement maps since V-Ray cannot always guarantee the surface continuity. Use other methods (vertex colors, masks etc) to blend different displacement maps."

 

Just doing a test render now.

Edited January 23, 2012 by stayinwonderland

[RyderSK]

Edit: Allright, I did a test. Keep continuity is 3D feature only, and works if you have different smooth groups assigned.

In 2D, simply using single smooth group helped.

Edited January 23, 2012 by RyderSK

[Tommy L]

try inverting he displacement map and using a negative disp value. An example of this working is subtracting mortar course instead of pushing out the bricks. Its a cheap trick but sometimes works well enough to get you by.