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How to reduce thickness in cloth self-collison? - xxxh123 - 17-09-2021

Hi! I am trying to fold a cloth mesh (i.e. T shirt) using self-collision on a table-top scene, but I find that the thickness of the cloth is too high when it is folded many times. How can I reduce the thickness of cloth under particle self-collision just like this? 
[Image: thickness_negative.png]
I have tried to reduce the radius of particles in the blueprint, but that often leads to penetration between two surfaces.

RE: How to reduce thickness in cloth self-collison? - josemendez - 17-09-2021

(17-09-2021, 10:21 AM)xxxh123 Wrote: Hi! I am trying to fold a cloth mesh (i.e. T shirt) using self-collision on a table-top scene, but I find that the thickness of the cloth is too high when it is folded many times. How can I reduce the thickness of cloth under particle self-collision just like this? 
[Image: thickness_negative.png]
I have tried to reduce the radius of particles in the blueprint, but that often leads to penetration between two surfaces.

If you reduce particle radius, then gaps might appear in-between particles that will lead to penetration (think of a "leaky" net)
If you increase mesh density in order to have more particles per surface unit, particles will be smaller -which will lead to a smaller collision gap- but the simulation will also be costlier because there's more particles.

So this is a tradeoff between resolution / particle size, and collision accuracy. This is one of the inherent limitations of a particle-based engine (which all existing realtime cloth engines are).

Obi adds an entirely surface-based collision pipeline to the basic particle-based approach: surface collisions. See:
http://obi.virtualmethodstudio.com/manual/6.2/surfacecollisions.html

These consider the entirety of the cloth surface for collision detection, not just particles. However this comes at a performance cost, which can be hefty for dense self-colliding cloth. You can try using them, but I'm not sure if they will be a good fit for your use case.

kind regards,