Curvature shader

V-Ray V-Ray for Maya Requests
1

Hi,

I am looking for a VRay shader or node which can render the same effect like this shader for Mental Ray.

http://www.tomcowland.com/mentalray/tc\_curvature/index.html

Is there any node inside VRay for these kind of shading effect?

Greetings Paul

2

There is currently no ready solution for this; you can get a similar effect using the VRayDirt texture with “invert normals” enabled. Otherwise, which of all the possible options for this shader would be most useful for you?

Best regards,
Vlado

3

The invert normals trick is working.

From the 1000 different attributes of the curvature shader I would choose :slight_smile:

Calculate from: Normal sampling
Method: Gaussian
Convex only (+ve)
Thats it, but I think that I can do it with the occlusion node.
Is it possible to bake this information into the vertex color directly with VRay?
As far as I know it is only possible to bake into texture files?!?

Paul

4

Maybe helpful, but not exactly the same concept:

5

Currently you can only bake to textures, yes. Other people have requested vertex baking though, so we’ll get there at some point.

Best regards,
Vlado

6

FR has a curvature shader that I was messing with that’s absolutely perfect. It doesn’t bake to vertex, and it’s really fast and great for certain effects (in this case, areas exposed vs. areas recessed on a rock face). Having to bake to vertex’s is a downside if you ask me..

Here’s the obligatory paper with tests to our favourite bunny:
http://www.cs.wustl.edu/MediaAndMachines/publications/papers/smi05tdg.pdf

7

I second the curvature shader request. Its one of the last really missing base shading functions. I know there isn’t such a thing as smoothly varying derivative for polygons but I have seen some cheats to get around that. And with smoothed subds you get close to how renderman approaches it.

Any thoughts Vlado?

im sure youve seen this…

http://www.tomcowland.com/mentalray/tc\_curvature/index.html

http://studentpages.scad.edu/~mparro21/curvature/curvature.htm

8

So uh, how’s about that vertex baking?

9

Heya,

to bring this topic up again:

I´ve found a new texture node which is called: BerconGradTex Is this maybe the curvature function I was asking for a while ago?
If yes, it crashes Maya instantly ^^ not possible to render it. Error msg is: Error: Exception : Rendering region (256,256)-(320,320)

I´m using Maya 2011 and VRay
[2011/Nov/3|16:16:45] V-Ray: V-Ray for Maya version 2.15.01, revision 17264 from Oct 28 2011, 07:32:07
[2011/Nov/3|16:16:45] V-Ray: V-Ray core version is 2.00.01

Thanks in advance

Paul