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Drop several cubes on the clothes as shown in the picture.
Then some cubes break through the clothes.
Please tell me how not to go through clothes.

I always respect you.

[Image: cloths.jpg]
Hi!

Many cubes on top of the cloth will cause the cloth to stretch due to their combined mass. This can open holes in the particle-based representation of the cloth, trough which cubes can pass.

Either reduce the mass of the cubes, increase the mass of the cloth, or  increase the amount of substeps (found in the ObiFixedUpdater component) to improve simulation quality and allow the cloth to resist heavier loads. Also, using more collision iterations will help with collision detection quality.

Alternatively, you can use surface collisions to extend collision detection to cloth faces, not just cloth vertices. This will make it harder for small cubes to slip in between particles.
(10-01-2022, 12:47 PM)josemendez Wrote: [ -> ]Hi!

Many cubes on top of the cloth will cause the cloth to stretch due to their combined mass. This can open holes in the particle-based representation of the cloth, trough which cubes can pass.

Either reduce the mass of the cubes, increase the mass of the cloth, or  increase the amount of substeps (found in the ObiFixedUpdater component) to improve simulation quality and allow the cloth to resist heavier loads. Also, using more collision iterations will help with collision detection quality.

Alternatively, you can use surface collisions to extend collision detection to cloth faces, not just cloth vertices. This will make it harder for small cubes to slip in between particles.

Thank you so much for your kind and detailed explanation.

One more thing, how do I increase the mass of clothes?
(11-01-2022, 01:49 PM)suxxexx Wrote: [ -> ]Thank you so much for your kind and detailed explanation.

One more thing, how do I increase the mass of clothes?

Hi!

Same way you can change any per-particle property: enter the blueprint editor, set the property dropdown to "mass", then select the desired particles and set their mass value. See:

http://obi.virtualmethodstudio.com/manua...setup.html
(10-01-2022, 12:47 PM)josemendez Wrote: [ -> ]Hi!

Many cubes on top of the cloth will cause the cloth to stretch due to their combined mass. This can open holes in the particle-based representation of the cloth, trough which cubes can pass.

Either reduce the mass of the cubes, increase the mass of the cloth, or  increase the amount of substeps (found in the ObiFixedUpdater component) to improve simulation quality and allow the cloth to resist heavier loads. Also, using more collision iterations will help with collision detection quality.

Alternatively, you can use surface collisions to extend collision detection to cloth faces, not just cloth vertices. This will make it harder for small cubes to slip in between particles.
the surface collision is not available for skinned cloth, is there a plan to add that?
(23-01-2022, 02:44 AM)nikov Wrote: [ -> ]the surface collision is not available for skinned cloth, is there a plan to add that?

Skinned cloth relies on skin constraints for collision "detection", for the most part. I don't see any advantage of using surface collisions for skinned cloth? May I know what is your use case?
(24-01-2022, 08:34 AM)josemendez Wrote: [ -> ]Skinned cloth relies on skin constraints for collision "detection", for the most part. I don't see any advantage of using surface collisions for skinned cloth? May I know what is your use case?
basically for dress/skirts, etc. If legs move too fast they go across the cloth and can't come back. This seem to happen mostly if leg movements are fast.
I wonder if there is a solution to prevent that?
(06-02-2022, 05:35 AM)nikov Wrote: [ -> ]basically for dress/skirts, etc. If legs move too fast they go across the cloth and can't come back. This seem to happen mostly if leg movements are fast.
I wonder if there is a solution to prevent that?

You can try increasing the solver's collision margin a bit:
http://obi.virtualmethodstudio.com/manua...olver.html

This will generate contacts before they actually happen, allowing the solver to be "predictive" rather than "reactive".

Also, using more collision iterations or more substeps will help. Increasing particle radius in your blueprint can also help close gaps in the cloth.