The goal is to simulate a cloth or softbody object that is full of air or fluid. For instance, a balloon which is squeezed or compressed on one axis, would bulge out in other areas. The extreme case is a dropped water balloon, although simulating that level of internal waves is above and beyond what I’m trying to get.
As I imagine anyone who has experimented with Blender softbodies has experienced, if your mesh is complex the softbody tends to collapse in on itself. This isn’t unexpected based on how the stiffness settings work, but frustrating. Jello-like simulations tend to only work with very simple meshes, or you have to add internal geometry that supports the outer surface.
Maya seems to have a method of adding internal pressure to an ncloth object as seen here. Is there any way to do this in Blender? I’d guess that an addon would be necessary, but perhaps there is a way to fake it with softbody targets or something like that?
I have had some success using the Molecular addon. For those who don’t know it, this allows you to create a volume of particles which link together and act like a solid. The links can be springy or break apart depending on the settings.
A particle volume with the compression stiffness set higher than the expansion stiffness behaves reasonably close to the goal: if one part is pushed in, the rest of the particle mass bulges somewhat. So this is a reasonable way to “fake” the behavior although it is more like jelly than liquid. The problem here is that you don’t keep the original mesh geometry. It’s possible to use CubeSurfer addon to create a new surface from the particles, which does generate a smooth mesh, but you lose the original UVs so you can’t texture it AFAIK.
I’m asking here to see if anyone has advice on simulating this kind of interaction on an existing mesh. I know that sometimes the only way is to animate it manually with bones or shape keys, but ideally I’d like to have an object interact with arbitrary colliders without creating a custom setup for each one. Thanks!