Hi there

I made a simple crowd with fish agents.
Just one state, which is swim.

My first problem is that the agents (fish) can change their heading only in
the xz plane. Since the swarm is not constrained to a ground plane,
how can I allow the fishes heading (controlled by velocity) to change in all planes?

The second question:
- I set up a crowd using “Populate” and “Simulate” from the shelf.
- Then set “Initial Velocity”, “Heading”, “Up” to 0 in the “Crowdsource” node.
> As soon as I add a POP node (ie pop force) in the simulation, I also get an
initial force on the Z axis. Why is that and where does it come from?

Any help appreciated

Marc Lauper
My first problem is that the agents (fish) can change their heading only in
the xz plane. Since the swarm is not constrained to a ground plane,
how can I allow the fishes heading (controlled by velocity) to change in all planes?

I think you want to allow the solver to modify the agent's up vector - this is controlled by the Adjust Up Vector parameter on the crowd solver.

Marc Lauper
The second question:
- I set up a crowd using “Populate” and “Simulate” from the shelf.
- Then set “Initial Velocity”, “Heading”, “Up” to 0 in the “Crowdsource” node.
> As soon as I add a POP node (ie pop force) in the simulation, I also get an
initial force on the Z axis. Why is that and where does it come from?

I think it would probably be useful to see an example file for that issue

Thanks cwhite. Up vector drop-down solves my problem.
As for the initial force; I have to investigate on that further.

Cheers