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View Full Version : Polygon flow problem with Catmull-Clark



Aracirion
01-29-2007, 07:17 AM
Hello

I am trying to model an airplane with Catmull Clark. On the cockpit windows I get the problem illustrated in the attachment. The red lines have sharpness 100, the others 0. Instead of the fuselage connecting smoothly to the edge of the windows, I get those weird bumps (arrows). Is there a way to solve this, or is this just the way catmull clarks work?

Wonderpup
01-29-2007, 11:25 AM
It might be worth checking for two point polys- they can cause this sort of effect.

Surrealist.
01-29-2007, 02:47 PM
Your problem is only related to CC in the sense that CC uses edge weighing which is your problem. Your windows are wieghed and the surrounding polys are not.

You can also see in that example the reason I believe Edge Weights are not a replacement for sound modling techniques - smoothing errors. I get the same problem with subpatch weights on points in Subpatch mode.

My advice is to rethink the model and add a little geometry. If you want to use the weight method you can experiment with it until you find a setting that does not create smothing errors. For this reason I have bagged edge weights for I have not found such a setting that gave me predictable shapes and no smothing errors. But there is no reason you - or I could not experiment with a combination of the two. Maybe someone else has had some success here, that has eluded me. :)