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Velocamonkey
09-14-2005, 05:49 PM
I'm trying to model some detail on a curved surface. So I've got some circular indents in it which I can model fine, see the first couple of pics. I can cut and end my edges efficiently and get a nice smooth circle. When it smooths it also keeps the curve of the surounding area and so the surface smoothly blends into this circular indent area. All is good.

PIC
http://www.michael-hull.co.uk/PROBLEM_01.jpg

My problem comes when I need to add more detail, have something that doesn't cut into the surrounding geometry quite so cleanly, like a square shaped indent as before, not a circle.

This means I'll need more cuts in the corners to maintain it's sharp edges when it is smoothed, but I can't seem to cut these in an efficient way without messing up the surrounding topology when smoothed. Please see my different approaches in the pics. I also tried as in the first picture, but finishing the edge loops at these corners, creating tris which is bad, and also it's not great when smoothed.

PIC
http://www.michael-hull.co.uk/PROBLEM_02.jpg


I would greatly appreciate it if you could shed even the smallest light on my problem, maybe I'm just missing something really obvious, but this is the only thing in modelling that keeps tripping me up!

Thanks for reading this, I appreciate the time.

GatorNic
09-15-2005, 06:30 PM
Three things you might consider trying, that come to me first...and I don't have Maya in front of me right now so I can't try them:

1. Instead of adding more edge loops, make some of the edges 'hard' and on the polysmooth use 'keep hard edge'. Its very particuliar how its done but I think it could work. And if you only want hard corners, but smooth edges...bevel the edges you want smoother but in conjuction with hard edge.

2. With the gemetry you already have...have you tried using the smooth sculpt poly brush on the particuliar areas you want smoother. (or sometimes it is better to use the pull sculpt poly brush but with a auto-smooth setting of like 3)

3. Same as #2, but a little more methodical is taking those particuliar vertices and doing an 'average vertices' on them to smooth them.

Velocamonkey
09-16-2005, 09:49 AM
Great, all sound like perfectly logical solutions, why didn't I think of them?! I'll give em a try and let you know. Thanks loads for the response, it was getting a little quiet in here.

mihkeltt
09-18-2005, 05:46 PM
exactly my biggest issue with modelling. if anyone could give a more general advice and not a maya specific solution - would rock my world :)

ares623
09-18-2005, 11:39 PM
try this thread.. it's for max though..
http://forums.cgsociety.org/showthread.php?t=40373

Velocamonkey
09-19-2005, 09:49 AM
Yay!! I'm not the only one! I tried these ideas here, the smoothing one and hard edges and what not, they didn't really work though in the way that I need, I'll check out the thread, cheers. Any other ideas? Surely everyone must have this problem? And if not know how to deal with it?

Velocamonkey
09-19-2005, 10:45 AM
ares623 (member.php?u=110227), is there an actual part in that thread that deals with answering my problem? I've been looking through it a while now and can't find anything yet, it's huge!

ares623
09-19-2005, 11:17 AM
ares623 (http://member.php?u=110227), is there an actual part in that thread that deals with answering my problem? I've been looking through it a while now and can't find anything yet, it's huge!
hehe yep its a huge thread..
try this page.. it's for creating holes on a curved surface though, but maybe you could use some of the techniques to get what you want. hope this helps. :) http://forums.cgsociety.org/showthread.php?p=483183&mode=linear#post483183

Velocamonkey
09-19-2005, 12:35 PM
Cheers for trying, but I'm all good with circular holes and details, as in my first pic, it was a little rough but I still know the concept of how to do them and get nice smooth results. it's just when Im trying to do square type details on curved surfaces that I stumble, anyone with ideas?

NicNac
09-24-2005, 12:28 PM
Yeah i'm having the same problem. Maybe this is the limit to Sub-D? haha :D

TonyEdwards
09-25-2005, 03:19 AM
Velocamonkey,

I think you're adding edges in the wrong places or you're unnecessarily adding edges to the entire object. The resulting loops you're creating at the corners of your square are too close together which is why you get a crease when smoothed.

Here's some examples I hope will help.

http://img384.imageshack.us/img384/5343/triscreen47jy.th.jpg (http://img384.imageshack.us/my.php?image=triscreen47jy.jpg)
As you can see, the “diamond face” used to merge three edge loops into one creates 3 and 5 edged vertices.
However, the derived surface remains completely uniform. This is because using poles allows you to terminate loops
abruptly while maintaining an all-quad surface.
If you haven't already I'd recomend reading the full article, by Tamás Varga, here (http://maxrovat.sns.hu/subdiv/). There are some great subdivision modeling tips there.

Here's an example of the technique mentioned above. Notice how Wiro is able to keep his topology clean and distributed. There are tutorials on his site as well at http://www.secondreality.ch/

http://img384.imageshack.us/img384/4605/screen002iw.th.jpg (http://img384.imageshack.us/my.php?image=screen002iw.jpg)

I'd try and show you an example with a sphere myself but I'm using someone else's computer; no 3d apps and no decent photo editor for me to draw on your image. :banghead:

Hope it helps.

Khorram
09-29-2005, 10:48 AM
What I've noticed from the pictures is that the surfaces are not complex, you can easily do that with Nurbs modeling and you will avoid those extra edge loops which just put stress on the surface. I suggest do it with Nurbs then convert it to poly or SubDiv if you need. Maya has enough tools to do what you've shown in those pictures. You will need Trim, Filllet and following some basic Nurbs modeling rules. And to do it by Polygons again I don't see any needs for those extra edge loops if you keep the geometry as simple as possible you will need just a touch of vertex tweaking in SubDiv mode to get a smooth surface. You better to apply a bevel with a narrow offset distance on edge loops inside the area where you want more definition.

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