u/UpsetAddress3828

What optimizations would you guys recommend I add to this setup? (Ignore the red squiggly lines, they're not connected to anything). I have a basic mannequin character that I animated in Blender (where he just torso twists and bends one arm) that I've imported into Houdini using the USD character import node. I wanted to add some tetrahedral simulations on top so he can eventually flop around like a zombie.

To achieve this, I used a timeshift to freeze the first frame of the animation, did the vdb from/to polygons, remeshed that so it's more accurate in Vellum. Then I used an attribute transfer to transfer a paint I did on the arm of the original model, to the same arm of the remesh. The pointwrangle simply adds everything not included in the paint to a group which the vellum sim will pin later on. From there I feed a point deform into the vellum tetrahedral setup, so the character now animates properly. The arm uses the attribute paint to flop around, which is controlled by a soft pin to target. The "hard" pin to target pins the rest of the body to the animation so it's effectively ignored by the simulation.

This is really slow. Like 30 frames per minute to calculate. I mean I know it's Vellum and tetrahedrals, but this isn't a very complex model or setup, and it's the only thing in the sim. If I don't have any pin to target/animation constraints, and let the tetrahedral model simply flop down to the ground, it calculates everything pretty quickly. Around 2-3 frames a second. Why is it that adding a pin to target slows down the calculation considerably?

Any insight would be appreciated. You can find a zip containing the hip file and the usdc file with the skeletal animation here if you'd like to take a shot optimizing the Vellum tetrahedral simulation. Thanks!