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Unity Engine

PhysicsCallbacks.ITriggerCallback

An interface that when implemented, can be called as a target by PhysicsWorld.SendTriggerCallbacks.
Read time 1 minuteLast updated 13 days ago

Definition

  • Type: Interface
  • Namespace: Unity.U2D.Physics
  • Assembly: UnityEngine.PhysicsCore2DModule
public interface PhysicsCallbacks.ITriggerCallback

Remarks

A trigger shape doesn't collide with other shapes. Other shapes pass through it instead. Unity calls 
OnTriggerBegin2D
and 
OnTriggerEnd2D
on the main thread after the simulation finishes. For a worked example, refer to the 
PhysicsShapeTriggerCallback
example in the Physics Core 2D examples repository
Additional Resources: PhysicsWorld.SendTriggerCallbacks, PhysicsCallbacks.IContactCallback

Examples

using UnityEngine;using Unity.U2D.Physics;// Add the PhysicsCallbacks.ITriggerCallback interface.public class DetectTriggerOverlap : MonoBehaviour, PhysicsCallbacks.ITriggerCallback{    void Start()    {        PhysicsWorld world = PhysicsWorld.defaultWorld;        // Create a trigger shape that reports overlaps instead of colliding.        PhysicsBody triggerBody = world.CreateBody(new PhysicsBodyDefinition        {            position = new Vector2(0.5f, 8f),            type = PhysicsBody.BodyType.Dynamic        });        PhysicsShape triggerShape = triggerBody.CreateShape(CircleGeometry.defaultGeometry, new PhysicsShapeDefinition        {            isTrigger = true,            triggerEvents = true        });        triggerShape.callbackTarget = this;        // Create a static shape for the trigger to overlap.        PhysicsBody staticBody = world.CreateBody(new PhysicsBodyDefinition        {            position = new Vector2(0f, 0f),            type = PhysicsBody.BodyType.Static        });        staticBody.CreateShape(new CircleGeometry { radius = 3f }, new PhysicsShapeDefinition { triggerEvents = true });    }    // Log when the trigger starts overlapping another shape.    public void OnTriggerBegin2D(PhysicsEvents.TriggerBeginEvent beginEvent)    {        Debug.Log("Trigger overlap started.");    }    // Log when the trigger stops overlapping another shape.    public void OnTriggerEnd2D(PhysicsEvents.TriggerEndEvent endEvent)    {        Debug.Log("Trigger overlap ended.");    }}

Methods

Method

Description

OnTriggerBegin2DCalled when a PhysicsEvents.TriggerBeginEvent for the object occurs. This will always be called on the main-thread after the simulation has finished.
OnTriggerEnd2DCalled when a PhysicsEvents.TriggerEndEvent for the object occurs. This will always be called on the main-thread after the simulation has finished.