Wednesday, January 16, 2013

Fixin that shoulder geo . . .

Here's a relatively quick video where I go over a technique I pulled from a Bay Raitt modeling time-lapse video like 10 years ago (vid is here). Basically, the idea is that to get more natural edge flow in the shoulder area, you just make a slight adjustment to the first extrusion from the torso which gives you a more natural angle to then extrude the rest of the arm. This helps a) make it more likely you'll model your arm at 45 deg angle, which I prefer to a t-pose when possible and b) help dictate the direction the edge flow wants to naturally travel.
As soon as I posted this on Vimeo, a fella named Ike commented (which I totally appreciate, btw) that maybe it sounded like I was bashing the idea that one should ever build a shoulder in the "tube" method, just extruding out of the torso in a straight line, and that, in fact, plenty of people model in this way and that it often works out (he gives some examples of his experience at The Mill and on Planet 51). To be clear, I totally agree with him! There a bunch of reasons why someone would model in a manner other than I'm proposing here. . . I've seen VERY senior and smart people pretty much advocating for a more "tube-like" approach. Some of the reasons they have mentioned (and I'd reprint the threads, but it was on a private message board and I don't feel like asking for permission to reprint all the stuff verbatim) include:
  • more even distribution of the geo makes it much easier to deal with driving the skin via other influences (like muscles layers, fat layers, etc)
  • more even distribution can make it easier to weight the skin sometimes
  • more even distribution also makes it easier to retopo if you have to later on.
  • sometimes the model just WANTS to be that way!
(note that often people advocating this work are in bigger shops, or have much more robust methodology for dealing with specific kinds of geo. Not always but often.)
Totally appreciate all of those reasons and wouldn't presume to argue with them. . . A good example is the clothing someone is wearing. . . obviously it doesn't make a ton of sense to model an edgeflow based on musculature when the character is wearing a heavy coat:) Despite the fact that I probably sounded more dogmatic in the vid than I intended to, my main point stands, in that you definitely want to look at reference for the way something is intended to move. For example, if you look at a man's blazer or tailored jacket, try to lay it out flat and put the sleeves in a T-pose. They probably won't do that, because that's not the way your arm naturally wants to move, hence the clothes aren't made that way! So while the edge flow would obviously be different than that of a muscly shoulder, it also wouldn't be a straight extrusion from the torso, either. . .
Also would add:
  • I'm, at least in part, concerned with passing info to my students, many of whom are learning about these things for the first time. The shoulder is a place on their models that frequently goes awry and this concept at least gives em a place to start. . .
  • I also work mostly freelance on commercial in NYC, often in smaller shops, and I often (maybe 20% of the time?) see geo that is actively harmful to my ability to rig a character:) So I feel like one is less likely to go wrong following edgeflow than one is just ignoring it.
  • Looking back, I have had plenty of good experiences with different styles of geo. Just wanted to say that too. . .
Also here's a link for some examples of different styles of modeling the shoulder area. ..
Enough about that! here's the vid:
Maya/Rigging/Modeling: Tip for creating better shoulder edgeflow from zeth willie on Vimeo.


  1. so easy, so simple..
    but so awesome.

    thank you very much !!

  2. Haha i love how you said that finding reference images is a good excuse for looking at topless women!

    Also this trick is a life saver and I'm glad i found this on your site.