vray displacement confined to one area

[stevesideas]

Hi there,

Is it possible to use texture channels or other methods to confine a vray displacement to specific faces on an mesh or poly ?

[Codi]

We use VertexPaint to mask areas of the mesh we want to displace, tomorrow I can post a sample scene if you need one.

[stevesideas]

That would be greatly appreciated Codi. Thanks a lot.

[stevesideas]

I ended up trying the vertex paint method...good one to remember, but I needed fairly accurate application of the displacement to a string of polys. I ended up using an unwrap uvw mod in channel 2 and then made sure that the mapping of everything else other than the bit I needed mapped was placed on a section of the texture that wasnt displaced..ie, RGB 128. Seems to work well, although it feels a little clumsy at the moment.

[Codi]

Ok, don't know if you ended with the same solution as us. A drawback of the vertex paint method is that you have to plan your geometry carefully, so the painted vertices fall in the desired place and you might also want to have surrounding ones to have a nice gradient.

What we do is apply VertexPaint modifier and paint-bucket all black, then either brush the desired area white or select the vertices that must be displaced and paint-bucket them white. Then we do a mask in the displacement channel between the map you use for the displace and a Vertex Color channel.

I've tried also modifying the UV's the way you suggest, but I usually end up with slices in the transition areas.

Another solution is painting a texture and mapping to the object, but it can be quite time consuming.

Hope it helps

[stevesideas]

Cheers Codi, very good of you.

I'll check out the file ta.