Cloth Interaction, and Pinning Vertices to Rig?

Hey everyone,

I have a couple questions involving cloth simulation. I’m working on a character model that will include clothes that I’d like to simulate, and I’m running into a couple issues. Right now I have the person as one mesh with a collision modifier, and a pair of pants with a cloth modifier.

Questions:

  1. Is it possible to use the cloth pinning feature to pin certain vertices to a rig? For example, I’d like the top edge of the pants to be controlled by the rig, but the rest of the vertices in the pants to follow the cloth simulation.

If not, is there another method that would accomplish something similar?

  1. I’m also having some problems with the cloth interacting with a collision object (in this case, the pants interacting with the legs). What I initially did was shrinkwrap the pants to the legs, then scale them outwards a bit. All parts of the pants were above the surface of the legs at this point. However, when I run the simulation, the top of the pants stay pinned like they should, but the nearest vertices freak out as if they’re intersecting with the mesh of the legs, when they aren’t visibly doing so.

If I scale the pants to be even larger and further from the leg mesh, this problem goes away, and the cloth sim works just fine. However, at this point the pants are too big and loose.

In the collision settings for the legs, I have the inner and outer surface settings set as low as possible, assuming that this number is the distance from the mesh that is considered the surface. However, searching around a bit, I’ve seen some people turn these settings all the way up to 1.00 - is this number controlling how solid the surface is? Or something else?

Any other potential issues or settings I might be missing or doing wrong?

Okay, I found a workaround for the second question - I scaled everything up x4, and even though the pants weren’t any farther from the body in relation to each other, they were farther in terms of actual distance, if that makes sense. No more cloth freaking out at that point.

Anyone know if it’s possible to do #1 above?

Use the pinning feature to pin the cloth to the model. The rig moves the model, the pinning moves the cloth, at least, the part of the cloth that’s pinned, probably the waistband and the legs down to around the knees (depending on the style of pants.)

It’s often not worth it to simulate cloth in pants except near the cuffs, since pant legs move pretty much with the body’s legs anyway, so the cloth might as well be pinned to the legs until you get down to the ankles. Extremely baggy pants are the exception, of course.

Thanks Orinoco. In this case, they actually are very baggy, so I think I’m in the exception. They’re not jeans or khakis or anything.

Unless I’m missing something, though, you can’t use the pinning feature to pin the cloth directly to the body or the rig, can you? Off the top of my head, the pinning feature is on/off, and a strength, but no settings to choose an object to pin to. Let me know if I’m missing something there.

One idea I had this morning that I’ll test later on is to parent the pants to the rig, then go into weight paint mode on the pants and paint 100% onto the pinned vertices and 0% on everything else. If I’m understanding it right, that would force the pinned vertices to follow the rig, and everything else will only follow the cloth sim.

You make a vertex group of the vertices you want to pin, then add that vertex group in the cloth pinning parameters.


See that group of seven dots? That’s the ‘vertex group’ icon.

I’ve found a tutorial that explains this better than I can. Pinning part of a piece of clothing to an armture bone starts around 8:30.

Yeah, I’ve been using the pinning feature, just not in conjunction with a rig.

Thanks for the link, though. That’s exactly what I was thinking, and that looks to be a pretty good explanation of the process. I’ll have to try that out tonight.