7. Collision

1. Collision

You can set up the collision object using ‘Create Collider’.  Select the hrSimulator node and the collision object, then press FXHair >> Create Collider

This process will create the hrCollider node and the hrColliderOffset node.

2. Nodes

This is the basic structure of the collision node.
 

The collision node is processed in this order;

Polygon mesh -> hrTriangulate (Triangular Poly Retopology) -> hrCollider (Collision Node) -> hrSimulator

You can check the shape of mesh through the shrCollider1Offset after re-topology or offset has been applied, and as shown in the node structure, hrCollider1Offset mesh will not affect the simulation result.

If you want to apply other hrSimulator with a collision object, connect the output attribute of hrCollider to collisionMesh of hrSimulator.

connectAttr hrColliderShape1.output hrSimulatorShape1.collisionMesh -na;

-Mel Script Example

connectAttr hrColliderShape1.output hrSimulatorShape1.collisionMesh -na;

3. Attributes

Active : Check the Active box to toggle the Collision on and off.

Offset: Sets the minimum distance between the collision object and the hair curve. The default setting is ‘0’ and any value above ‘0’ is set, the collision range will be broader than the object, and any value less than ‘0’ is set, the collision range will be narrower than the object.

The offset parameters can be checked through the hrColliderOffset mesh.  In the diagram below, the blue color represents the collision object and the red color represents ‘hrColliderOffset’ altered by the offset attribute.
 
 
 

Friction: The friction force that affects the collision object.

Priority: This attribute allows you to prioritize the collision objects when there are more than two hair curves. The object with lower number in the Priority setting will be calculated preferentially.

Written by Sol Kim