Houdini 19.5 Nodes Dynamics nodes

POP Steer Avoid 2.0 dynamics node

Applies anticipatory avoidance force to agents/particles to avoid potential future collisions with other agents/particles.

Since 14.5

This is a crowd behavior node, but you can also use it on regular particles (see the Output attribute parameter).



When this is off, the node will have no effect. You can animate this to turn the behavior on or off at different times.


Only modify a certain group or groups out of all agents/particles. You can name groups of agents using the Group name parameter on the Crowd Source geometry node.


Controls if the guide geometry for this node should be shown.


Even if it is enabled here, it can also be disabled by using the Hidden flag on the DOP Node.

Output Attribute

If you are working with agents, set this to “Crowds steerforce”. If you are working with particles, set this to “POP force”.

This controls whether the node modifies the agent’s steerforce attribute (used by the crowd solver) or the particle’s force attribute (used by the POP solver).


Available when Output attribute is “Crowd steerforce”. This number is used by the crowd solver to normalize and scale multiple forces that apply to an agent.

Particle Scale Multiplier

The node uses pscale as the size of each agent/particle when calculating potential collisions. You can use this parameter to scale the value of pscale in the calculation, letting you allow agents/particles to be more or less tightly packed. This parameter can be overridden by a pscalemultiplier point attribute.

Force Scale

Scaling factor for the strength of the avoidance force.

Anticipation Time

How far into the future an agent will look for possible collisions (this uses current velocity to project the possible distance). The maximum distance for which an agent considers another agent as a neighbor is the minimum of the agent’s current speed multiplied by the Anticipation Time, and the Neighbor Distance.

Neighbor Group

Specifies the agents/particles that should be considered when searching for nearby agents.

Neighbor Distance

Maximum distance an agent searches for other nearby agents.

Max Neighbors

Maximum number of nearest neighbors to an agent to consider when computing the agent avoidance force.

See also

Dynamics nodes