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Help  Can softbody be used on cloth?
#1
   
   
   

Softbody sphere

I want to drop it on the cloth.

the position of softbody collisions is unstable.
how shall I do it?

gif file will not play click to see.
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#2
(02-06-2023, 03:31 AM)astest Wrote: Softbody sphere

I want to drop it on the cloth.

the position of softbody collisions is unstable.
how shall I do it?

gif file will not play click to see.

Hi,

Hard to tell what the problem might be without further details. My advice at this stage would be to add a ObiParticleRenderer component to both the cloth and the softbody to see how well their particle representations collide against each other, it might be necessary to create a finer representation of them.

kind regards,
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#3
(05-06-2023, 05:53 PM)josemendez Wrote: Hi,

Hard to tell what the problem might be without further details. My advice at this stage would be to add a ObiParticleRenderer component to both the cloth and the softbody to see how well their particle representations collide against each other, it might be necessary to create a finer representation of them.

kind regards,

Please understand my poor English. Sorry

In the example scene of obi, there was an example of dropping a ball on a cloth.

The ball was hard.

I want to use the ball as a soft body and drop it on the cloth.
If you imagine the production, you can think of it as a case of dropping a water balloon onto the cloth.

However, when using the soft body, the collider is not stable like the gif image above.

Continuously shaking, unable to settle gently on the fabric and penetrating without colliding into the collider area.

Is this possible?
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#4
(06-06-2023, 02:05 AM)astest Wrote: Please understand my poor English. Sorry

In the example scene of obi, there was an example of dropping a ball on a cloth.

The ball was hard.

I want to use the ball as a soft body and drop it on the cloth.
If you imagine the production, you can think of it as a case of dropping a water balloon onto the cloth.

However, when using the soft body, the collider is not stable like the gif image above.

Continuously shaking, unable to settle gently on the fabric and penetrating without colliding into the collider area.

Is this possible?
Hi!

It's entirely possible, but how well it works depends on how well the particle representation of both the softbody and the cloth approximate their surface. That's why I suggested you to add a ObiParticleRenderer component to both, to be able to visualize the particles and debug collision detection.

Note that Obi is a particle-based engine, so collision detection between objects is performed using particles. If the object's representation is too sparse (meaning large holes in between particles, or badly placed particles) then collisions will be irregular or even cease to work completely.

kind regards,
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#5
(07-06-2023, 09:21 AM)josemendez Wrote: Hi!

It's entirely possible, but how well it works depends on how well the particle representation of both the softbody and the cloth approximate their surface. That's why I suggested you to add a ObiParticleRenderer component to both, to be able to visualize the particles and debug collision detection.

Note that Obi is a particle-based engine, so collision detection between objects is performed using particles. If the object's representation is too sparse (meaning large holes in between particles, or badly placed particles) then collisions will be irregular or even cease to work completely.

kind regards,

I added ObiParticleRender and tried it.

collision between the softbody and Cloth does not occur properly.

I need to add colliders to make each other react
Adding a collider to Cloth makes it hard.
Adding a collider to a soft body will cause the soft body to fly in a strange direction, or will not return to its original state when it is crushed.

I didn't know what to do, so I filmed the phenomenon.
Please help me in a little more detail. Thank you.

https://drive.google.com/file/d/1NAcZ_4e...sp=sharing
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#6
(08-06-2023, 04:08 AM)astest Wrote: I added ObiParticleRender and tried it.

collision between the softbody and Cloth does not occur properly.

I need to add colliders to make each other react
Adding a collider to Cloth makes it hard.
Adding a collider to a soft body will cause the soft body to fly in a strange direction, or will not return to its original state when it is crushed.

I didn't know what to do, so I filmed the phenomenon.
Please help me in a little more detail. Thank you.

https://drive.google.com/file/d/1NAcZ_4e...sp=sharing

There's a fundamental misconception here: adding Collider component to cloth or softbody doesn't make any sense and will interfere with the simulation. The reason is that Colliders are designed to work with Unity's Rigidbodies, since they cannot deform.

For the same reason, adding a ObiCollider component is also completely unnecessary. Colliders are designed to make cloth/softbodies react to regular geometry in the scene, such as walls, floors, etc. I'd recommend reading the manual page about collisions:
http://obi.virtualmethodstudio.com/manua...sions.html

Obi is a particle-based engine. This means that all aspects of simulation - including collisions- are performed using particles. There's no need to add a Collider to a cloth or softbody for them to collide with other objects, since particles already take care of that. However, you must make sure that the particles in your objects don't have huge gaps in between them (such as the ones seen in your video) since that will allow objects to pass in between particles. The simplest solution is to make your particles bigger, tweaking their radius in the cloth/softbody blueprint editor.

kind regards,
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#7
(08-06-2023, 09:09 AM)josemendez Wrote: There's a fundamental misconception here: adding Collider component to cloth or softbody doesn't make any sense and will interfere with the simulation. The reason is that Colliders are designed to work with Unity's Rigidbodies, since they cannot deform.

For the same reason, adding a ObiCollider component is also completely unnecessary. Colliders are designed to make cloth/softbodies react to regular geometry in the scene, such as walls, floors, etc. I'd recommend reading the manual page about collisions:
http://obi.virtualmethodstudio.com/manua...sions.html

Obi is a particle-based engine. This means that all aspects of simulation - including collisions- are performed using particles. There's no need to add a Collider to a cloth or softbody for them to collide with other objects, since particles already take care of that. However, you must make sure that the particles in your objects don't have huge gaps in between them (such as the ones seen in your video) since that will allow objects to pass in between particles. The simplest solution is to make your particles bigger, tweaking their radius in the cloth/softbody blueprint editor.

kind regards,


As I told you, I've grown the particles in the particles, but they don't collide

Adjusted to Property-Radius value in Blueprint.

I removed all the colliders and obi colliders.

Isn't it this? T_T

   
   
   
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#8
(08-06-2023, 10:17 AM)astest Wrote: As I told you, I've grown the particles in the particles, but they don't collide

Adjusted to Property-Radius value in Blueprint.

I removed all the colliders and obi colliders.

Isn't it this? T_T

If they don't collide at all, check that:

1.- Both the cloth and the softbody belong to the same solver. Actors in different solvers won't interact with each other in any way, since they're part of different simulations. See:
http://obi.virtualmethodstudio.com/manua...olver.html

Quote:Each solver is completely independent from other solvers. Therefore, actors being updated by different solver won't interact / collide with each other. Only actors in the same solver will react to each other.

Just realized that in your video you seem to have 2 separate solvers, one for the cloth and another one for the softbodies. This will ensure they are simulated separately and don't know about each other's existence.

2.- Particle collisions are globally enabled in the ObiSolver component, under the "constraints" foldout.

3.- Collision filters are properly set up for both the cloth and softbody (that is, they're not set to ignore each other's category). See:
http://obi.virtualmethodstudio.com/manua...sions.html

4.- The mass of the cloth and the softbody particles are comparable, you can check this in the blueprint editor. If the softbody is much heavier than the cloth, it will push it out of the way and end up passing trough it.

kind regards,
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#9
(08-06-2023, 10:57 AM)josemendez Wrote: If they don't collide at all, check that:

1.- Both the cloth and the softbody belong to the same solver. Actors in different solvers won't interact with each other in any way, since they're part of different simulations. See:
http://obi.virtualmethodstudio.com/manua...olver.html


Just realized that in your video you seem to have 2 separate solvers, one for the cloth and another one for the softbodies. This will ensure they are simulated separately and don't know about each other's existence.

2.- Particle collisions are globally enabled in the ObiSolver component, under the "constraints" foldout.

3.- Collision filters are properly set up for both the cloth and softbody (that is, they're not set to ignore each other's category). See:
http://obi.virtualmethodstudio.com/manua...sions.html

4.- The mass of the cloth and the softbody particles are comparable, you can check this in the blueprint editor. If the softbody is much heavier than the cloth, it will push it out of the way and end up passing trough it.

kind regards,


Thank you very much!!! It's working fine.
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