polygon to subdiv
 

hi guys im working on a model, and im regularly switching between polygon and subdiv, but every so often ill change something on the polygon model (add a few edges or delete some unnecessary ones) and itll stop converting into a subdiv, everytime i try to change it, it will say result 0, i can still apply a smooth but its no subdiv.

anyone know what causes this? and if there is a solution?

Hi Chilled,

It's been a while singe I've used the poly-subD route for modelling. As far as I can remember you get strange non converting results with non manifolds and tris I.E non quads. The history may also build up and cause problems depening on the changes.

Personally I would now advise using purely polys and using the smooth mesh preview for smoother iterations of the model for previewing the smooth poly (as I'm sure thats what your going to render in)

Jays the best for sub-d's as he knows the whole shizazle when it comes to modeling, NURBS, Polys and Subs.

Cheers

Steve

thanks for the advice .
i have to admit im following a tutorial thats why im converting to sub div, of course the tutorial guy never has this problem. lol
yea your right about the smoothing thing, thats how the finished model will be rendered, just using the sub div to push and pull a few things. :D

Thanks Steve

Yeah Subds have their little probs in the convert every so often.

I take it from what you're saying its purely in the switching to and from the SD surface.

Usually its a build up of history on the sub-D surface which is basically called blind data. These nodes do have their uses but in modelling they can cause a bit of trouble. To get rid of them simply go to the hypergraph with the model selected and graph the up and downstream connections. This will show you all the nodes attached to the geometry, from the actual shape node right down to any history.

If there are any blind data nodes visible, delete them. But make sure you have deleted all the history too on the model otherwise it may not work. Hopefully this is the problem and you should now be able to carry on. Also be aware that sometimes the model may just seem to disappear, this is one of Mayas little quirks, so simply check the Outliner and make sure its all there, select the model and re-apply a shader to it.

Another prob with conversions to sd's can be points that may not be merged or left over from a deleted edge or an edit. Run a cleanup from the Poly menu set, anything that is wrong will get hilighted.

Lastly, Ive not used Subds for a while since the intro of the 3 key command to convert to a smooth poly. Its just as good as good if not better as subds can become heavy once you start placing those level edits on them, so bear that in mind, and also texturing needs more attention because of the smoothing algorythm place on them too.



hope this helps
Jay

yea that is a great help, i was just gonna ask if it is better to use poly smooth, i have to admit not having to switch to subdiv could be nice :)