constrain multiple objects to a plane

[FIELD]

Hey Peeps,

Im new to Houdini and currently trying to get into its dynamics system.

Ive setup a simple scene that looks like a 2D arcade game (super mario) - multiple elements fall down and collide with the 'level' geometry - that all works fine.

Now I'd simply like to constrain the falling elements to always stay on a 2D plane (z=0) but cant figure out how to setup the DOP nodes.

I guess one would use a Constraint + Hard Connection Relationship + Anchor Object Space Position + Anchor World Space Position nodes - correct?

If so how do you set them up so the constraint works with all elements of the fractured object?

Any tips / help please?

Cheers

Marcus

[kubabuk]

have a look at the apply relationship dop

[anim]

what about just setting position Z and velocity Z to 0 each timestep?

maybe at the end of the dop tree to override all objects?

[FIELD]

what about just setting position Z and velocity Z to 0 each timestep?

maybe at the end of the dop tree to override all objects?

@Tomas

that's exactly what Im trying to do - is there a simple way to do this?

I tried an apply data + position node after gravity but that didnt seem to affect anything.

@Kuba

the relationship dop is a bit overwhelming, but it seems that once i have the plane constraint working for a single object that behaviour could be copied onto all other objects with it?

[anim]

here it is

just setting tz to 0

DOPs_RBD_2D.hipnc

[FIELD]

here it is

just setting tz to 0

Oh wow - thanks Tomas!

Your example works fine, but when i try to apply it to my fractured rigid body object only one of the elements is constrained to the plane.

Will try and experiment a bit more, but at least that points me in the right direction ...