Version: 2019.4
  • C#


struct in UnityEngine


Implemented in:UnityEngine.VehiclesModule

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Contact information for the wheel, reported by WheelCollider.

Friction for the WheelCollider is computed separately from the rest of the physics, using a slip based tire friction model. This allows for more realistic behaviour, but makes wheel colliders ignore standard PhysicMaterial settings.

The way to simulate different ground materials is to query WheelCollider for its collision information (see WheelCollider.GetGroundHit). Usually, you get the other collider the wheel is hitting, and modify the wheel's WheelCollider.forwardFriction and WheelCollider.sidewaysFriction based on the physic material of the ground.

The other members of the WheelHit structure are usually queried for information purposes or special effects. For example, a "slipping tire" sound can be played if forwardSlip or sidewaysSlip exceed some threshold.

See Also: WheelCollider.GetGroundHit.


colliderThe other Collider the wheel is hitting.
forceThe magnitude of the force being applied for the contact.
forwardDirThe direction the wheel is pointing in.
forwardSlipTire slip in the rolling direction. Acceleration slip is negative, braking slip is positive.
normalThe normal at the point of contact.
pointThe point of contact between the wheel and the ground.
sidewaysDirThe sideways direction of the wheel.
sidewaysSlipTire slip in the sideways direction.