Help Question about garment onto a 3d avatar using Obi

[onfitpark]

This is entirely up to you. You can designate which actors should collide with other actors using collision filters.

kind regards,

Hi,
I have faced another problem with collision. I have confirmed in relation to Category and Collides With; and I got it was possible between the body mesh(having Obi Collider) and a cloth(adjust the value in Blueprint), which was good to know.
Next, I'd like to make two clothes collide each other so that top should be set the outer layer, always, as I asked questions in the previous post. And with the manual, it should be working but it seems like it didn't work.

I was wondering if I did it in a wrong way or not. Here is how I set the value.
_body mesh w/ distance field: in ObiCollider, Collision cateroty> 0 / Collides with> Everything
_cloth 1(top): in Blueprint, select all(Particle selection all red), Category> 2, Collides with> 0,1,2
_cloth 2(pants): in Blueprint, select all(Particle selection all red), Category> 1, Collides with> 0,1,2

After seeing that nothings has changed yet, I tried to add Obi Collider component to each clothes and set Category and Collide With value, and I saw the two clothes were just crumpled. I guess Obi might be confused with 3 different Obi Collider working at the same time.

I was wondering if there's a way that two clothes collide each other so that they were well worn on the body, (not intruding each other's surface).




Second, I reduced Collision margin value to 0.001, and I saw the clothes still intrude each other. So is Collision margin nothing to do with collisions in my situation?
*Additional question*: like a waist band of a pants in real life, is there an effect a cloth to shrink towards the body mesh?(I mean the center of an mesh, object, etc.)  

Third, the cloth is slippery and seems like a light cloth like silk. I have look through the manual below.
distance- https://obi.virtualmethodstudio.com/manu...aints.html
bend- https://obi.virtualmethodstudio.com/manu...aints.html
However, since I generated SkinnedCloth, I don't see some of the parameters. When I change the values according the manual, the outcome isn't really changed.
If there's a way that I haven't found yet to give a cloth to some physical properties like less stretch?
Please let me know.


Thank you, always.

[josemendez]

Hi!

After seeing that nothings has changed yet, I tried to add Obi Collider component to each clothes and set Category and Collide With value, and I saw the two clothes were just crumpled. I guess Obi might be confused with 3 different Obi Collider working at the same time.

Adding a ObiCollider component to a cloth doesn't make any sense. ObiCollider should only be added to colliders, as the name implies. See: http://obi.virtualmethodstudio.com/manua...sions.html

Keep in mind that Obi is a particle-based engine, so cloth already has its own collision geometry: particles. No need to add colliders to it.

I was wondering if there's a way that two clothes collide each other so that they were well worn on the body, (not intruding each other's surface).

This should happen by default, as long as particle collision constraints are enabled in the ObiSolver component and there aren't any large gaps in between particles. You can add a ObiParticleRenderer component to the cloth to visually inspect its particles, and see if you should increase their radius in some areas.

Second, I reduced Collision margin value to 0.001, and I saw the clothes still intrude each other.  So is Collision margin nothing to do with collisions in my situation?

Reducing the collision margin will make matters far worse, as particles have less margin to react to nearby particles when moving which will make missed collisions more common. You should instead increase it (be careful as very large margins will have a negative performance impact).

*Additional question*: like a waist band of a pants in real life, is there an effect a cloth to shrink towards the body mesh?(I mean the center of an mesh, object, etc.)  

Yes, you can reduce the stretch scale parameter in the cloth's distance constraints.

Third, the cloth is slippery and seems like a light cloth like silk. I have look through the manual below.
distance- https://obi.virtualmethodstudio.com/manu...aints.html
bend- https://obi.virtualmethodstudio.com/manu...aints.html

If the cloth is slippery or silk-like, it is because it has zero friction when colliding with other objects. Friction is a property of collisions, not internal to the cloth itself, so you can set it in the cloth's collision material. Increasing static/dynamic friction on either the cloth or the colliders it is colliding against will make collision less slippery.

However, since I generated SkinnedCloth, I don't see some of the parameters. When I change the values according the manual, the outcome isn't really changed.

SkinnedCloth has more parameters than regular cloth, not less. Could you specify which parameters you're trying to find on the skinned cloth?

[onfitpark]

Hi again!


I have one parent Solver, and two garments that are Skinned Cloth applied. In runtime, each garment "works" properly; no drops and penetration. But when they are put together at the same time, then I see bottom(pants, under layer) garment slightly dropping down slowly. So I changed top to other garments but still it happened.
I have no idea why this situation happens.
Could you please explain the reason and the solution to this?

Thank you

[josemendez]

Hi again!


I have one parent Solver, and two garments that are Skinned Cloth applied. In runtime, each garment "works" properly; no drops and penetration. But when they are put together at the same time, then I see bottom(pants, under layer) garment slightly dropping down slowly. So I changed top to other garments but still it happened.
I have no idea why this situation happens.
Could you please explain the reason and the solution to this?

Thank you

Hi!

Cloth actors are completely independent from each other, they don't interact except via particle collisions. There's no reason for them to behave differently in presence of other actors. If this is what you're experiencing, could you give some more details and maybe post a short video of the issue so that we can diagnose it?

kind regards,

[onfitpark]

Hi,

attached is two videos!
I hope I make it right.

Thank you

---

[josemendez]

It's not very clear from the second video, but it looks like the bottom part of the shirt is colliding against the waist part of the pants?. Collisions between particles will keep them awake, causing them to slowly drop down due to insufficient friction against the body. This is only speculation as I don't know what your collision/sleep threshold parameters are.

You mentioned you're using ObiSkinnedCloth for the cloth, in that case this can be easily solved by setting the skin radius property for the waist particles to a very small value so that they don't deviate from their original positions.

kind regards,

[onfitpark]

It's not very clear from the second video, but it looks like the bottom part of the shirt is colliding against the waist part of the pants?. Collisions between particles will keep them awake, causing them to slowly drop down due to insufficient friction against the body.

Hi,

thanks for the reply. I agree with your opinion.

I've set 0 sleep threshold, 0.02 collision margin, and I reduced the skin radius value 0.05 to 0.0001, which I think 'very small', but nothing has changed yet. The pants still slowly fall down from the waist to the pelvis. One weird thing is that other short pants aren't affected falling down by any other top clothes. Even the shorts get 0.05 skin radius value(default blueprint setting).

Is there another way to come up with other solutions to this problem? Please let me know.

Thank you



*While waiting the reply, I increased the vertex count of the mesh(pants) doubled, and set negative value of skin backstop radius. It seemed less falling down compared to previous work, but still was affected by shirt I guess.