So I have a sim of a snowground and a character going through it. But whenever I try to emit and fire a snowball towards the character mid-sim, the snowball gets flattened instantly, as if there's a non-moving velocity field around it that squishes it.

I already tried adding a volume source to the mpm solver with the snowball having a velocity volume generated, but this gives errors.

How would something like this be achieved?


When I sim it seperately (first the ground, later a sim for the snowball), the snowball stays round.

Just found out that upping the Global Substeps and enabling Particle-Level Collision (Velocity Based) prevents this problem, but that's a very cost heavy way plus it changes the look of the whole sim.

If anyone knows I'd be interested to know why if the whole snowball has the same velocity on every point still gets crushed flat when sourcing it. If I'd simulate/emit the snow ball from the start it'd not have this problem.