Help Cloth to simulate slime

[arrnav96]

Here:



The video starts with the basic cloth setup: Create a GameObject with cloth & solver components, choose a cloth topology (I have multiple ready-made ones, so I skipped topology generation) and hit "Initialize".

Then I fix the four corners of the cloth (similar to the setup you describe), and create a 1 kg ball on top of it.
Click play, and the ball sinks trough the cloth. ([1:18] in the video)

Note that I left the cloth mass at its default value of 0.1 kg per particle, for the sake of demonstrating iterations/substeps only. First I try 5 iterations / 2 substeps. Since the cloth mesh is quite dense -made out of many particles- and light, the ball still slips trough. Then I try 5 iterations / 4 substeps, and now cloth is able to withstand the weight of the ball, despite having a mass ratio of 1/10. Reducing the mass ratio by increasing the weight of the cloth would reduce the need for high iteration/substep counts, reducing the density of the mesh would too.

After that, I add a particle renderer component so that you can see the cloth particles. Then begin to reduce the amount of substeps again, until the ball is able to rip a gap between the particles and slip trough.

Hope the video helps you.

PS: I have a feeling that your original goal got lost during this conversation... assuming your slime sim is 2D, I think it would be both easier and much more performant to simply move particles around directly (those near the user's finger), using Oni.SetParticleVelocities()?

Thankyou. Your support is astonishingly helpful. I'm going to try that setup tonight as soon as I get home.

That being said, originally, as you mentioned in the end, I wanted to move particles around the user's finger using SetParticleVelocities(). But I'm unable to understand how would I be able to create a finger's shape on slime's surface. 

If I attenuate positions of particles around the user's finger using a slope equation, I don't understand how that would recreate a "finger shape".

Is increasing substeps really inefficient for such use cases?

I feel the only thing stopping me from using SetParticleVelocities() is the finger shape on surface. 

Also, do you have suggestions on how to make the cloth more "Slimy"? I tried altering values such as stiffness but can't quite get it right.