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Unity Engine

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Unity Engine

OnTriggerEnter(Collider)

Called when a collider enters a trigger collider.
Read time 1 minuteLast updated 10 days ago

Definition

OnTriggerEnter()

public void OnTriggerEnter(Collider collider)

Parameters

collider

Collider

Remarks

OnTriggerEnter
is called on whichever iteration of the physics 
FixedUpdate
loop Unity first detects that the collider has entered the trigger. The colliders involved are not always at the point of initial contact when Unity detects the collision. Both GameObjects must contain a Collider component. At least one of the colliders must be a trigger collider and at least one must be a physics body collider. For more information, refer to OnTrigger events. Both the trigger and the collider that touches the trigger receive 
OnTriggerEnter
if they have implemented it. Trigger events are sent to disabled MonoBehaviours to allow enabling Behaviours in response to collisions.

Examples

using UnityEngine;public class Example : MonoBehaviour{    private float speed = 2f;    //Moves this GameObject 2 units a second in the forward direction    void Update()    {        transform.Translate(Vector3.forward * Time.deltaTime * speed);    }    //Upon collision with another GameObject, this GameObject will reverse direction    private void OnTriggerEnter(Collider other)    {        speed = speed * -1;    }}