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Weetos
12-04-2004, 03:47 AM
Hi

I have a problem with a human model I've made, and I think I may miss something. I used standard tools (extender,smoothshift,drag...) and I obtained a pretty clean geometry, but when it came to the muscles shape I had to use spinquads and since then I got a bad polyflow, especially some points connected to 5 or 6 polygons that cause shading problem. Do I have to start over from the start or is there a way to get rid of those and recover a detailed but clean geometry?

any help would be greatly appreciated :rolleyes:

Lottmedia
12-04-2004, 10:44 AM
Had the same thing happen on one of my models, in about the same places. There are just some places where geometry gets bunched up if you don't watch yourself. Had to eventually re-build sections to get better flow. It's annoying but you'll have a better model for it. You end up just pushing pollys around and not wanting to sacrafice this completed work and it never gets better. I've found just choose a problem section and build a replacement in the background and see how it fits.

J-Rod

spud_q
12-04-2004, 11:17 AM
I have found that usually when you render the errors are not as bad as they are in Modeler sometimes open GL is extra bad about showing creases. If it still looks really bad and you donít mind the extra geometry I usually clean it up by subdividing metiform and re-stitch the problem arias. Then I use the band glue tool to reduce the mesh back down to an acceptable polygon count.

hrgiger
12-04-2004, 11:26 AM
Well, part of the reason you get creases is from having one point share more than 4 polygons. 5 is usually ok like some of the areas on your model, but they are covering a fairly large area and they are trying to define a curve coming from 5 different directions of the polyform so that's why they crease. It's all about directional flow. Triangles can also cause creases but dont' let anyone tell you that you shouldn't use them. You just have to know where and when to use them. But generally, if you can keep most of your geometry to quads, that's optimal, at least while we have to deal with no ngons in Lightwave.
You don't have to start over, but you might want to consider deleting a couple of those areas and extending some new polys into the area.
I would be happy to rebuild an area or two for you as an example (I would place it in the background layer so as not to change your base model so you could compare them) Let me know.

HR

Weetos
12-05-2004, 07:34 AM
Thanks for your replies, now I know can go on instead of start over, which is good ;)

hrgiger, I'm still learning organic modeling so I really appreciate you offer, and knowing where to go thanks to your directions could help me a lot. Thanks again for sharing your experience :)


here's the lastest version of my model

hrgiger
12-05-2004, 08:05 PM
Hey Weetos, hope you don't mind but I took a quick look at your model tonight and made a few changes. I reworked one area of the model to maybe show you how you could get rid of those creases. As I said, I think you just have a few areas where you have too few polys trying to define a contour. This first picture shows you what I did. Obviously the part I changed is highlighted in green.

hrgiger
12-05-2004, 08:09 PM
Oh, and here's something something else you might find helpful. I can tell you work mainly in subpatch mode ;) . Personally, I like to model in polygon most of the time because if your mesh is easily readable in polygon form, you'll get the cleanest easily editable mesh. Here is yours in poly form and after I did some general teaking.

Again, I hope you don't mind, just giving you my .02.

Weetos
12-06-2004, 02:18 AM
Wow... Thank you bunches hrgiger for the time you spent on my dirty model !! you did help a lot. I think I'll first have to clean up this messy thing in poly mode ! What do you think, do I have to clean only some areas or maybe freezing the whole thing with a sudivision level set to 1 would help to get a cleaner base from what I then would be able to add the needed extra geometry? Anyway I guess I'm not yet done with that guy when I look at it :rolleyes:

Ok, back to work now :D

Thank you again for having been so helpful

Kind regards

Weetos

thekho
12-06-2004, 03:21 AM
Just it is an opengl. Try a render which will looks so fine without creases.

Weetos
12-06-2004, 04:24 AM
yeah thekho, I found it renders fine :) , it's just that I want to get a good poly flow so it can render good even if it is deformed by bones or dynamics.

hrgiger
12-06-2004, 04:50 AM
Yeah, it is not so much the creases that are the problem, because it is an openGl issue for the most part but the reason I stress having a few more polys in such a large area is that you'll find it deforms better. It's walking the balance of having enough polys to define the shapes you want in both static model and deformation but also not having so many polys that it is inefficient to work with.

Actually, yeah I have learned weetos (although I don't use it anymore since I'm used to modeling in poly mode) is you can freeze your model like you said and make sure to set your subpatch division to 1 in modeler before you do. That way, you won't add any more geometry when you freeze it but it will help smooth out your base model. Some tweaking will be required afterward though as it may smooth out some areas a little too much and you might lose some of the defined areas (like the pecs flowing into the deltoids for instance).

Weetos
12-06-2004, 05:12 AM
hmm I got it cleaned up by freezing, it smooth way too much certain areas. I think I'm going to start from the smoothed version and see what I can come up with without messing too much with the polygon form. I'll have to add geometry where the details are located, instead of dragging points too far like I used to do

I'll post the result when I'm done, if anyone is interested in my quest for the Great Holy Polyflow ;)

hrgiger
12-06-2004, 07:36 AM
Well, the less geometry you have in your model, the more that subpatching and freezing it will alter it's shape when it smooths it out. As I said, its' not a technique I use anymore, I just rely on pulling points until I'm happy with it.

Weetos
12-06-2004, 02:23 PM
Ok I cleaned it up a little instead of working from the smoothed version. I did so because I've ended up with almost the same messy thing when I added the details.

I reworked the part following hrgiger's advices and I added hands. does it now look ok or should I focus on more cleaning? anyone?

Thanks