I'd like to build a character from the spine up who can be used for distant shots, can be procedurally animated easily, and can be modified to be male, female, fat, skinny, short or tall. My ideal setup would be a completely procedural model that can be animated and deformed without having to go through IK.

This way, I can setup all of my param()'s and have each character inherit it's own unique size, shape and animation for crowd simulation.

I remember way back in some older versions of Houdini there was a SOP called the “arm” or “limb” sop. It allowed for you to setup a simple IK arm/leg at the SOP level.

I'm running into obvious problems with my model… the lack of a skeleton being a big one of those problems. I'm basing everything off what is essentially a bone structure built from points (connected with polys) which looks very much like a stick figure. I have nice deformations on the hips, shoulders, kneck and spine but I'm running into problems with the limbs.

Obviously, without IK my “human's” legs poke through the floor whenever I drop the hips down. If I lock the feet to the floor, my legs just get shorter as I lower the hips down. This is all to be expected.

But is there a way in a point sop or otherwise to fake IK so this doesnt happen??? I wonder…

IK has to know a few things to work. 1.) how many bones 2.) distance between those bones 3.) distance to maintain between bones 4.) bone root 5.) bone goal and 6.) bone hierarchy

This isnt exactly easy for me to impliment. I wonder if any of you have had success animating characters this way (remember, this is for distant shots) using deformations instead of IK and more specifically if any of you know how to “fake IK” at a procedural, SOP-based level.

If I have to, I'll go into the world of real IK == but I'd like to keep everything as procedural as possible. That is, if IK is even possible for use with crowd sims. Most ideal would be 100% procedural. It's a lot to ask, but… any ideas?

In theory, I think you can use param()'s in bones as well.

Thanks, although one reason behind my idea to build everything procedurally was to free myself from the bounds of IK… if I can build a procedural character who's deformations come from the bones up (spline based, basically) I can multiply the character many times before running into serious slowdown issues. 100 IK skeletons with param()'s in the bones could take forever to bake through. It may be my only option though…

My other option of course is to build a good sized library of looping animations in Poser (yes, Poser – perfect for posing people and exporting geometry sequences) and then use those instead.

The most ideal setup would contain either nice models brought in off disk or run through an IK solver, alongside procedurally built models for use in the background.

I'm really very interested in the possibility of finding a way to “fake IK” using something as simple as a 3 point spline, where points 0 and 2 are the goal and root, and point 1 is the knee.

The math for doing 2 bone IK is definitely doable. You just need to draw it out and work it through. It's basically just a triangle. Keep in mind though that there will usually be two solutions and so you want to make sure to pick the one closer to your rest pose.

Yesterday, someone over on the ZBrush Forum posted a link to the Blender MakeHuman project, which is currently in beta - http://www.dedalo-3d.com/index.php?filename=SXCOL/makehuman/news/mahehuman20winter01_is_out.html [dedalo-3d.com]

I'm not saying it's what you're looking for, least of all as it isn't ready yet, but it may be interesting just to have a peak…