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Unity Engine


OnCollisionEnter(Collision)

OnCollisionEnter is called when this collider/rigidbody has begun touching another rigidbody/collider.
Read time 1 minuteLast updated 7 days ago

Definition

OnCollisionEnter()

public void OnCollisionEnter(Collision collision)

Parameters

collision

Remarks

In contrast to OnTriggerEnter, OnCollisionEnter is passed the Collision class and not a Collider. The Collision class contains information about contact points, impact velocity etc. If you don't use collisionInfo in the function, leave out the collisionInfo parameter as this avoids unneccessary calculations. Notes: Collision events are only sent if one of the colliders also has a non-kinematic rigidbody attached. Collision events will be sent to disabled MonoBehaviours, to allow enabling Behaviours in response to collisions.

Examples

using UnityEngine;using System.Collections;public class ExampleClass : MonoBehaviour{ AudioSource audioSource; void Start() { audioSource = GetComponent<AudioSource>(); } void OnCollisionEnter(Collision collision) { // Debug-draw all contact points and normals foreach (ContactPoint contact in collision.contacts) { Debug.DrawRay(contact.point, contact.normal, Color.white); } // Play a sound if the colliding objects had a big impact. if (collision.relativeVelocity.magnitude > 2) audioSource.Play(); }}