Houdini 20.5 Nodes Dynamics nodes

Agent Terrain Projection dynamics node

Project the agent/particle points onto the terrain

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Since 14.0

This node projects agents/particles onto the terrain.

Parameters

Activation

1 activates the node. 0 deactivates the node.

Group

The group of agents that this node should affect.

Terrain Source

Source for the terrain object (SOP path or DOP object).

SOP

Use the SOP specified in the SOP Path parameter.

DOP Data

Use the DOP specified in the Terrain Object parameter.

First Context Geometry

Use the SOP connected to the DOP network’s first input.

Second Context Geometry

Use the SOP connected to the DOP network’s second input.

Third Context Geometry

Use the SOP connected to the DOP network’s third input.

Fourth Context Geometry

Use the SOP connected to the DOP network’s fourth input.

SOP Path

The path to the SOP (when the terrain source is set to SOP).

Terrain Object

The DOP object to use as the terrain geometry. This can also be specified as an object/data path for using specific geometry data attached to an object. For example, popobject/Geometry.

This parameter is only available when the terrain source is set to DOP Data.

Terrain Group

The primitives in the terrain geometry to be used for ray intersections.

Mode

Controls the direction of the terrain projection.

Direction Vector

Use the direction specified in Direction.

Up Attribute

Use the agent’s up attribute.

Direction

Direction of the terrain projection when Mode is set to Direction Vector.

Sampling Method

Specifies whether to cast a single ray from the agent’s point (Particle), or cast a ray from each of the agent’s legs (Foot).

Sample From Agent’s Plane

When Sampling Method is set to Foot, projects the foot positions onto the plane defined by the agent’s position and the Direction vector before casting rays. This produces results that are consistent with the Particle sampling method if the agent is on flat terrain. If this option is turned off, the agent will be lowered by the average distance of each foot from the terrain.

Offset

Additional offset that will shift all the agents up or down.

Project Forces

When turned on, the force point attribute will be projected onto the plane defined by the terrain normal.

Normal Attribute

When turned on, an attribute will be output indicating the normal of the terrain geometry underneath the agent.

Prim Num Attribute

When turned on, an attribute will be output indicating the primitive that the agent was projected onto in the terrain geometry.

Prim UVW Attribute

When turned on, an attribute will be added with the coordinates of where the agent was projected onto the terrain geometry.

Offset Attribute

When turned on, an attribute will be added with the agent’s offset from the terrain (according to the Mode, Sampling Method, and Offset parameters). This can be used in combination with the primitive number and UV coordinates to stick agents onto deforming terrain geometry.

Inputs

Agents

The packed primitive agents to modify.

Outputs

Agents

The modified packed primitive agents with terrain projection applied.

See also

Dynamics nodes