Wrap that soft body

In the last week I’ve been working on new underwear and bra. For a long time I’ve wanted to make clothing that can hold up a chest, trying to get two physics based objects to interact with one another.

First I had to make the two clothing pieces and get a design down. The underwear got the look of some kind of mix between male and female panties, that way it can be used for all genders.

For the bra I went with something that look like a unisex sportsbra. I made two versions, one where the straps are separated and one where they merge into one on the back.

The one where the straps merge on the back was modeled a bit wrong. It needs to connect near the neck.

Since Blender doesn’t support individual cloth objects to interact with one another, I have to join the clothing meshed with the body mesh. This method is pretty destructive as it alters the body mesh now that it also have clothing. I made a copy of the body mesh and added the clothing to that one, that way I always have the original. The result looked pretty nice but it occurred to me, what about the fur underneath that needs to be flattened or hidden.

I needed to find a different method for this situation. And I ended up doing the more normal thing, making the body not interacting with the clothing and cheat instead. The normal method also makes it possible for the clothing to flatten the fur with the help of dynamic paint.

To make it work, the body mesh needed a small tweak to the belly button. The method need the character mesh to have a slightly larger self-collision distance, going from 1 millimeter to 1.5 millimeters should work, but making it 2 should make the clothing even more stable. But giving the body larger self collision made the belly button go twitchy, as the points that build up a mesh were too close to one another. By making the belly button slightly roomier, allowed the body mesh to have increased self collision, which allows the clothing to have more room to slide into and between, for example under the belly.

To make it look like the underwear and bra hold anything, I first let the simulation run where the body is slightly thinner than the end result, then bake the cloth sim for the clothing. I increase the fatness of the character, and run the simulation again with collision on the clothing, this makes it look like, in this case, it’s the bra that hold up the breast. It’s back and forth but gets the job done.