mental ray will not render my subd model??
 

Hi guys, I have another newb problem.

I have a model and when I convert it to subd and try to render it with mental ray (draft default) the dragon head does not render and I get the following error message:

select -r polyToSubd1 ;
deleteInternalValence2Verts |polyToSubd1|subdTessShape1;
polyToSubdiv -ap 0 -ch off -aut on -maxPolyCount 1000 -maxEdgesPerVert 32 |polyToSubd1|subdTessShape1;
// Warning: Nothing is selected. Select objects or components to delete. //
// Result: polyToSubdShape1 //
delete |polyToSubd1|subdTessShape1;
// Error: (Mayatomr.Geometry) : polyToSubdShape1, non-quadrilateral face in subdivision surface base mesh not supported, ignored //

Maya software will render the head, maya hardware does the same thing as mental ray but gives no error message.


What have I done wrong? Is it correctable?

Here is a picture to help. The top one is the model converted to subd then rendered with Maya software. The bottom is the same model rendered with mental ray (draft).

Do you have any faces that are have more or less than 4 edges?
As of right now, MentalRay will not handle subD's from Maya with none quad geometry. The easiest method is to take it in ploy mode or on your low poly mesh and smooth it once. Or go in manually and edit the mesh to be all quads.

ACk! I have a number of tri's. Try as I might there were some areas that I just could not figure a way to make into quads without adding lots of unessessary faces or very narrow faces that would be hard to avoid creases in.

I was not sure I followed your instructions about smoothing?

Did you say take the model back to poly mode and do a level one smooth on it?

Aside from manual converting all the tri's to quads is that the only methed available? I noticed something labeled "quadrangulate" in the poly menu but I could not figure how to do anything useful with it.

Thanks for the info Pony. I'll give it a try. I was trying to avoid smoothing as the model is already up to 625 faces (half the head) and I did not want to add the geometry that a smooth is going to add because it will start to become hard to work on a model that has lots of dense geometry.

I feel your pain. well I would say convert to polys and do a level 1 smooth on it.. but you might have edits on subD that you could luse. I'm not sure how you have it right now. Although not the most thrilling option I figure your best bet is just to kill the tries buy hand. If you really want a MR render. A posibility would be for renders only to convert it back to poly with a high tensilation just befor render. MR will handel any poly's that are trie or N'gons.

I feel your pain, its a bummer MR will not handle them.