Help How to setup collision matrix for obi colliders?

[erdoganhuse]

Hi,

I am trying to seperate obi collisions just like Unity's collision matrix. For example there are Emitter A, Emitter B, Obi Collider A and Obi Collider B. I want emitted particles from Emitter A to collide with just Obi Collider A. I did not achieve such seperation for more than 2 layer with changing Phase value.

Thanks.

[josemendez]

Hi,

I am trying to seperate obi collisions just like Unity's collision matrix. For example there are Emitter A, Emitter B, Obi Collider A and Obi Collider B. I want emitted particles from Emitter A to collide with just Obi Collider A. I did not achieve such seperation for more than 2 layer with changing Phase value.

Thanks.

Hi there,

Set Emitter A and Collider B to phase 1.
Set Emitter B and Collider A to phase 2.

That would make emitter A to collide with collider A, but not with collider B. Emitter B would collide with collider B but not with collider A. Is that what you were referring to?

[erdoganhuse]

Yeah, what I am trying to achieve is that but with more than 2 emitters and colliders. There are 4 emitters in my scene and 4 specific colliders for each of them. I dont think setting Phase like that work with more than 2 layer.

[josemendez]

Yeah, what I am trying to achieve is that but with more than 2 emitters and colliders. There are 4 emitters in my scene and 4 specific colliders for each of them. I dont think setting Phase like that work with more than 2 layer.

Hi,

I see. You can't achieve this with phases, and we can't use a full collision matrix for particles. Unlike with regular rigidbodies, it is not uncommon in Obi to have tens of thousands of contacts per frame. Filtering them using a collision matrix could get really expensive.

Can you provide more details about your use case? There might be alternative ways to achieve what you want.

[erdoganhuse]

Hi,

I see. You can't achieve this with phases, and we can't use a full collision matrix for particles. Unlike with regular rigidbodies, it is not uncommon in Obi to have tens of thousands of contacts per frame. Filtering them using a collision matrix could get really expensive.

Can you provide more details about your use case? There might be alternative ways to achieve what you want.

Of course. I have 4 pipe like objects in my scene and some of them overlaps with each other. At the top of each pipe there is a fluid emitter and couple of them emits fluid at the same time, because of that emitted fluids that belongs to specific pipe, also collides with overlapping pipes. I want emitted fluid to collide with just one pipe.

Actually changing collision logic for phase will be sufficient. If objects with same phase value collides with each other, my problem will be solved.