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jrandom
02-20-2010, 06:57 PM
In the attached image you'll see a few "tears". Those tears are not only not in the non-SubD mesh, but what appear as two opposite edges of a tear are actually only one edge and can only be selected as such -- the tear cannot be repaired by merging since there are aren't two separate edges to combine.

What causes this and how can it be avoided?

Dexter2999
02-20-2010, 07:06 PM
Can you post this? I'd like to check it please.

probiner
02-20-2010, 07:06 PM
-Try to unweld and merge
-Try to select all polygons or edges and go to Map>Weight>Set Sharpness and use 0%
-Try to look for '1 vertex' and '2 vertex' polygons.
-Try to be patient, since Catmull-Clark can be very very annoying in LW =)

IgnusFast
02-20-2010, 07:06 PM
Only time I've ever seen that is when I have un-merged vertices. Your mileage may vary. :)

jrandom
02-20-2010, 07:33 PM
Here's the object file. (A lot of the surfacing uses the IFW2 nodes, so if you don't have those you'll probably see all sorts of errors on startup. It shouldn't affect the shape of the thing, however.

I'm seeing this problem in the layer called "Lower Panels", although it's cropped up a lot, usually when using multi-shift, bandsaw pro, and subdivide.

This is my first real SubD experiment, so I'm learning as I go.

On a related node, Add Edges doesn't seem to mirror in symmetry mode (only affecting one half of the model). Is this normal?

jrandom
02-20-2010, 07:44 PM
Try to select all polygons or edges and go to Map>Weight>Set Sharpness and use 0%

Detail->Edges->Set Sharpness->0% did it! Weird. After that I was able to play around with different sharpness settings with no tears, and I can get new tears when multi-shifting/bandsawing polys/edges that are already at 0% sharpness.

At least I know how to fix them now. Thanks!

probiner
02-20-2010, 08:52 PM
jrandom, preety model man, i opend the file and got amazed by the simplicity and beauty of the thing. Good Luck

It's very easy to see this happeing in Catmull Clark. Especially if you use Edge Weightning.

Edge Weightning is a great way to do Partial Sharp Edges, avoiding dense meshes from Subpatch control edges and still do things that Subpatch Weight can't do.
Catmull is also great because you can have Subdivided and Regular geometry connected that it won't break.

Still, in LW the Edge Weight brings this kind of issues all the time. Especially if you are still editing the mesh. Setting the Sharpness of everything to 0% in the affected area fixes it, but if you already had the job of weighting the mesh, you have to do it again =(

Cheers

http://i153.photobucket.com/albums/s202/animatics/Lightwave/Catmull-issues_b.png