Iray Shaders not working on OBJs imported from Rhino 7?

7th Stone Productions

I've modeled a few items in Rhino 7, which I would like to use in Daz Studio, and render using Iray shaders.  However I cannot seem to get the Iray shaders to work on these imported OBJ models. I was wondering if anyone might have a clue as to why this is?

DETAILS:  I created a few items with NURBS in Rhino 7 and then converted them to quad meshes, and exported them as OBJs. After importing the OBJs into Daz Studio, if I apply an Iray shader (Asphalt or a Wood for example) the overall color of the shader applies but not the color variation, pattern, or bump. I've analyzed the meshes in Rhino and there doesn't appear to be anything wrong with them. The normals and everything check out. I've also examined the shaders setting in Daz, and even tried adjusting the tiling to no effect.

Has anone run into this problem before, or might have a clue as to why this is happening?

Thank you.

Richard Haseltine

Are the models UV mapped?

7th Stone Productions

No, the models are not UV mapped. That is the next thing I intend to try. I would not have thought that UV mapping was necessary to simply apply a shader. The Daz primatives are not UV mapped are they? ...and yet the Iray shaders work on them. I just don't have enough knowledge in this area.

Richard Haseltine

yes, the primitives are UV mapped. The sahder is applying, it just can't generate a pattern without UVs as a source for the position.

Mattymanx

If the shader is NOT dependant on images, than it will still work and look fine.  However, as Richard has already stated, if what you want to apply requires images to work, then it needs to be UV mapped.  UV mapping is not all that hard.  Once you wrap your head around it, pun intended, you will be just fine.

7th Stone Productions

Thanks Richard and Mattymanx for straightening me out on that. It seems that the illness and five year forced hiatus from CG work did more damage to my knowledge and skills then I first realized (including a smalll stroke). I find myself spending a lot of time relearning things lately.