Invisible mapping in preview

[willunwin]

Occasionally when working with some materials (woods, brushed metals, etc) it is not possible to see a preview of them on the actual model itself when setting the scene up. This makes it very difficult to see whats going on if i'm trying to map them in a particular way. Somethimes if i tweak the glosiness or something similar a preview will then show up, but might then dissapear later.

Is there any reason why this happens? I was thinking maybe the bitmap used was to small or something...but thats just a guess..

Any thoughts would be greatly appreciated.

Thanks,

Will

[dalomar_cg]

Re: Invisible mapping in preview

What exactly are you expecting to see? The Rhino material is limited in terms of what it can really show within the viewport. Basically, at this point, all we can really show is diffuse information. Any reflection, refraction, emissive, or bump info won't be shown in the viewport.

[willunwin]

Re: Invisible mapping in preview

Ah..that probably explains it. I have a brushed steel material from the internet. The bitmap(of the scratches) is located within the reflection drop down menu under the fresnel option. I suppose if it were within the diffuse dropdown I would be able to see it?

Thanks

[dalomar_cg]

Re: Invisible mapping in preview

yep that certainly does. Here's a little trick that might help in this situation. I'm assuming that you have a diffuse layer that's contributes to the material and is opaque (can't see what's underneath). Just add a dummy diffuse layer with the map you're trying to see. The diffuse layer that is at the top of the stack will be the one that shows up in the viewport, so when you're working in the Rhino viewport drag the dummy layer on top. Once you're ready to render drag the dummy layer below the one that you actually want rendered and you should be fine.