Wow, the speed with which you edited the pillow in this video is nothing short of impressing. Also, 64 threads?! What kind of monster have you managed to enslave inside your computer?

About the Optitex plugin, while I don't have the complete version (I started relatively recently with Daz and by that time it was quite apparent the whole thing was going nowhere fast) I know one of the "premium" parameters it's internal pressure. I don't quite know the nuts and bolts of it, but it's used in the tutorials for their, quite appropiately, pillow set:

https://www.youtube.com/watch?v=7y6CZ577tK4

https://www.youtube.com/watch?v=0POm6CV97KU

I believe it's also used in their promo video for their backpack:

https://www.youtube.com/watch?v=KheDlUfEQSM

Also, thanks for your explanation, for some reason, imagining a mesh filled with tetrahedrons appealed to the gamer in me (those 4 sided dices can be deadly... when walking barefoot). One thing I don't quite understand, though: if using the second method and applying a vector along the normal of a node, couldn't this be applied to a partially open mesh, or even only to a part of it? Let's say, in keeping with the thread's theme, could we make something like this:

My experiments with clothifying human figures tell me there would be lots of "cloth-like" wrinkles, so, not really (also, rigging would be lost, so animation would be out, unless there was a way to fit a rigged figure as a collider inside of the simulated figure that moved it like an skeleton without deforming it too much... maybe even using a literal skeleton, now that I think of it, as the old one has Victoria 4's rig and should be animatable without any hassle, or even fit inside the original figure and copying its movements from the timeline). But if there was any method to get some internal pressure on the human's body... well, that would also work for simulating punches, having tight clothes on (the infamous "muffin top", for instance) or even a "femenine bounce" with energetig movements. Darn, it's far too late for me to keep on rambling, so I will try and stop here. Hope that wasn't too overwhelming, but this tool really makes me want to push things in unexpected directions. Thanks once again for providing it for us, and for your attention to your clients. Really, it is very much appreciated.