Help on how to debug a model

[puzzledpaul]

Difficult to give specifics without seeing the culprit - but if you suspect you've got overlapping (duped) verts

Smoothing the mesh often gives you some clues - by checking 'flow'

Select the whole imported object and try Object | Separate - and see what you get (details shown in Window | Geom Graph)

If you have suspicions about a particular area / region - but can't figure out what's happening ... I sometimes just go into Tools | Tweak and move a few verts around ... to see if there's other stuff lurking underneath etc (then use undo when done)

pp

[Xxaxx]

Hey PuzzledPaul

Separate did not do anything I could see.
Smooth worked like a champ (as smoothing).
The model looks fine after smoothing (but a ton of vertices.) :-)
No doubles were revealed by the tweak.

For this one model I wouldn't mind just remaking it.
However, since this is a persistent problem, if I can find a work flow that fixes it, then I can avoid a ton of future duplication of effort.

If all went well, there should be a copy of the file attached to this posting.
Take a look if you have time. I'm looking at this as a learning experience to become a better wings3d user and modeler.


(http://forums.cgsociety.org/attachment.php?attachmentid=114563&stc=1)

[puzzledpaul]

First, (if these are early attempts at using wings AUV) I'd suggest trying something simpler, with quads where possible.

Apart from anything else, 'reading' edges etc on a quad based model is generally easier than one that's tris.

I don't have time to mess around with this - but if you think of this as a paper model ... that you wanted to unfold and lay flat (or as much as poss) ... then there's some areas that *really* need attention, like the armpit and buttock crease :)

If you're gonna continue with this'un - try creating more (logical) segments so's it opens out better in AUV

Since you intend using this as a 'learning exercise' ... you could also try cutting up the model into smaller chunks and try AUV on each of these smaller parts, in an attempt to find what type of situation causes the problems?

pp

[Xxaxx]

Well, the models I am making from scratch are mailboxes, ceiling vents, turnstiles, toasters, and an occasional bowl of fruit -- mostly simple transformations of the basic cube and/or cylindar. I love da quads and only build in quads at the moment.

That's sorta why when it comes to people, I was hopeful I could purchase an inexpensive model off Turbosquid.

You are correct that some types of areas are not prone to un-wrapping without problems. But I expected those problems to result in weird looking texture maps. This is exactly what happened in an early attempt at unwrapping my toaster -- weird texture map, but no badarith. However, when unwrapping a model I've imported from TurboSquid it's about 80% badarith. Made from scratch in Wings3d 0% badarith, out-sourced through Turbosquid 80-90% badarith.

The learning that I'm looking for is how to work with out-sourced models.

I'll try the cutting it up into smaller pieces idea. But I'll be surprised if this is a simple issue of more logical subdivisions. Notably when I do a smooth the resulting model will run through AUV just fine. So the armpits and butt crease are no problem for the AUV after a smooth has been done. I'm assuming that during the smooth process the engine is putting the vertices into some kind of form that is more compatible with its math.

I was just hoping to find a way to do this "putting into some kind of form that is more compatible" without doubling or quadrupling my number of faces through smooth.

Thanks for the input. I'll poke around a bit and let you know if I stumble on a solution.

Regards,

[puzzledpaul]

Just had a quick look (again)

The problem is around the neck area - RH side, rear
There's duped verts + 1 isolated one.

(using Tools | tweak on this area will show you the problem)

Select object
Object | Cleanup ... eyeball top left info (before / after use) which'll tell you how many etc.

Cleanup will only get rid of duped verts that (are co-incident) and connected by an edge - if the geom is folded back on itself, then it won't do anything.

Also can find (for isolated verts, not dupes)
Select > By > isolated vert or verts with 2 edges.

I stripped the current materials and re-applied default
Took into AUV and segmented by feature detection
Unfolded ok.

Imo, this is a horrible model, btw - compare geom (edgeflow) with that seen on other decent ones (like at subdivisionmodelling.com)

pp

[Xxaxx]

PP,

Thanks for your patience and your help.

The "object -> cleanup" and "select -> by -> isolated vert" are a great help. This should help clean up a multitude of issues.

But even more so, thanks for the link to subdivisionmodeling.com

Looks like a great resource for learning the "finer" artistry of modeling.

Thanks again.

Claude
p.s. In fairness to the original modeler of the chunkette you saw, that was produced by running a severe polygon reduction on the orginal. The model went from 23,000 to 2k. That was sure to introduce some less than elegant looking edgeflow.

[puzzledpaul]

Glad you're finding some of the info useful.

<< p.s. In fairness to the original modeler of the chunkette you saw, that was produced by running a severe polygon reduction on the orginal. The model went from 23,000 to 2k. That was sure to introduce some less than elegant looking edgeflow. >>

That explains a lot.
However (the poly redn app) has made quite a few decisions that (imo) could fairly easily be improved upon ... without necessarily adversely affecting the overall poly count (assuming you wanna stay with tris)

Converting / 'tidying' this model back to quads'd probably be an interesting exercise in its own right ... and first thing would be to create a central edgeloop so's you could use VMirror on it :)

pp

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