Vector displacement using vRay

[DPGrafik]

Hi,

I've been looking through the threads in this forum about vector displacement, and last night i tried it out using Mudbox 2012. I cannot get it to work. I tried just to use the standard method and the 10 step procedure that someone posted somewhere where you switch the green and blue channel i think it is.

Has anyone gotten it work?
And what about using vector displacement with PTEX does that work as well.


Thanks !

[DPGrafik]

i've tried to simplify things abit and just make a ordinary color map using ptex on a cube in mudbox. When i load the ptex file in the vray ptex node and attach it to a shader and object. maya crashes every single time..
Has anyone gotten this to work?

i'm using the latest nightly build
Maya 2012 - Snow leopard

[Yannick]

Have a look here:
http://www.chaosgroup.com/forums/vbu...r+displacement

[DPGrafik]

As I mentioned in the first post. I've tried the suggestions in said thread. But with no luck. I'm now stuck to the point where Maya crashes every single time I load a PTex file. I've also installed the latest nightly build of vray today so maybe there is a bug with PTex in that build?

[vlado]

Can you post a scene that crashes here or email it to me at vlado@chaosgroup.com ?

I haven't tried vector displacement with PTex yet, so I can't confirm if it works or not - I have to make a few tests.

Other than that, I'll try to post an example for regular vector displacement from Mudbox a bit later.

Best regards,
Vlado

[DPGrafik]

Hey vlado that sounds great!

But have you noticed anything with PTex in general using the latest nightly build? Every type of PTex map both color and displacement is crashing Maya. I'm gonna try and roll back a few versions this weekend and see if the crash relates to a specific vray build


I'll email you the scene tomorrow

[DPGrafik]

Hey Vlado,

any news with the ptex issue? Is it a vray bug or did i setup my scene wrong?

[DPGrafik]

If anyone is interested. The problem with Ptex is only present when using a nightly build - at least for me. I've switched to the latest stable build og vray 2.0 and ptex works - for texture maps like color.

But with Vector displacement, it does not work.
Has anyone had succes using vector displacement map with vray in maya?

[jbuttell]

I haven't had any luck with vector displacement yet. Seems regardless of what I feed in, it displaces the polys, but doesn't subdivide them. In my test scene with low poly model, it just pushed the faces out, apart from their UV seams..

I feed a similar map into the regular displacement and it subdivides/generates more polys as needed. I have no idea why it doesn't appear to work.

[DPGrafik]

Yeah, i get the same error. No subdividing and just polys pushed apart so the model breaks. I've tried a least a dozen different ways of connecting the ptex node to the displace node and again to the shading group. Since it's originally connected as ordinary displacement but the displace node does have a vector displace input/input but that doesn't change the end result i'm afraid.

[vlado]

But with Vector displacement, it does not work.
Has anyone had succes using vector displacement map with vray in maya?

Vector displacement requires valid UVs on the mesh. This is because the vector displacement values are relative to the UVN vectors of the surface. This is the only way to do vector displacement if you plan to deform the object (anything else doesn't make sense really - object space or world space obviously don't work for deforming meshes). So, even though the PTex file itself doesn't need UVs, you still need to have them for vector displacement to work.

Best regards,
Vlado

[vlado]

Here is a short tutorial on rendering vector displacement from Mudbox through regular (OpenEXR) files:
http://www.spot3d.com/vray/help/maya...splacement.htm

Best regards,
Vlado

[VasilVelikov]

i've tried to simplify things abit and just make a ordinary color map using ptex on a cube in mudbox. When i load the ptex file in the vray ptex node and attach it to a shader and object. maya crashes every single time..
Has anyone gotten this to work?

i'm using the latest nightly build
Maya 2012 - Snow leopard

I just found out what the problem was and I've fixed. It should be ok in the next nightly build.