The Storm Situation And A Crazy New Idea

Hi there.

I am currently working on the last part of Nadia's face rigging; her forehead.

What follows is some very techno-geeky stuff..  So I will not be offended if you want to pass on the rest of this post.

I posted earlier that I had an idea for finishing Nadia that will save a lot of time using Storm.  Storm has this awesome new feature making it possible to be used in character rigs... Firmly attaching soft bodies to bones and such.  It's so great.

Unfortunately it's not so great yet... It has some bugs.  Sometimes it works, other times it doesn't.  The last time I tried it, it worked for the initial test, and then when I completed the model it did not work.  So while it is possible Storm will perform well for Nadia's rig, I think the odds are not good.  The developer told me he does not know when he will have time to fix the problem.  I asked him if it would be safe to say he could get to it in the next 2-3 months.  Even that he could not commit to.  Most unfortunate.  So Storm can be an amazing part of my process in the future but it's not ready quite yet.

Earlier today an idea popped in my head; a crazy new concept that is not quite as good as Storm will be, but is the next best thing.  Some of you have seen my soft body work using my cloth simulator with an internal lattice of springs.  Math eggheads call this Finite Element Method (FEM).

The problem is my cloth simulator is not so good at all with self-collisions.  It approaches self-collisions by assigning a weight value to specific vertexes (points) in the model.. These vertexes are given a radius of self collision.  They only see other self-collision vertexes...  They do not see polygons.  If the radius is small enough to slip by the three or four self-colliding points of a polygon, then you can get the awkward results of geometry looking like it's stuck together.  I've done tests with this and it's quite unpleasant.

What I always did was set up the outer shell/skin to be the self-colliding group.  But it hit me a few hours ago; what if I do not use the vertexes on the outer skin of the model for self collision?  What if I choose vertexes deeper within the model?  I can then increase the radius of the self-collision to reach the outside skin.  Because they are considerably larger, the issue of points slipping between and getting stuck is dramatically reduced, if not removed completely.  So the skin does not collide with the skin.  This is why I call it Subdermal Self-Collision.  The insides collide with the insides, and because all of that is connected to the skin with springs... they carry the skin along with them as they collide.  It's not as precise as Storm would do it, but as I said.. Next-best-thing.

This could be the most amazing idea since velcro.  I'll do some tests after I finish up Nadia's forehead rigging.  Stay tuned!