---
title: TriggerVolume
framework: realitykit
role: symbol
role_heading: Class
path: realitykit/triggervolume
---

# TriggerVolume

An invisible 3D shape that detects when objects enter or exit a given region of space.

## Declaration

```swift
@MainActor @preconcurrency class TriggerVolume
```

## Overview

Overview A trigger volume is an entity that can participate in collisions because it has a CollisionComponent. You use a trigger volume as a sensor that indicates when another collision-capable entity, like a ModelEntity, enters the region of space occupied by the trigger volume. You can use the generated CollisionEvents between the trigger volume and the other entity to trigger an action, like indicating to the user that a projectile hit its target.

The trigger volume itself is very simple. It lacks any physical appearance, and doesn’t participate in physics simulations. This makes it very efficient for tasks that require only collision detection.

## Topics

### Creating a trigger volume

- [init()](realitykit/triggervolume/init().md)
- [init(shape:filter:)](realitykit/triggervolume/init(shape:filter:).md)
- [init(shapes:filter:)](realitykit/triggervolume/init(shapes:filter:).md)

### Accessing the collision component

- [collision](realitykit/hascollision/collision.md)

### Detecting collisions

- [Configuring Collision in RealityKit](realitykit/configuring-collision-in-realitykit.md)

## Relationships

### Inherits From

- [Entity](realitykit/entity.md)

### Conforms To

- [CoordinateSpace3D](spatial/coordinatespace3d.md)
- [CoordinateSpace3DFloat](spatial/coordinatespace3dfloat.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [Equatable](swift/equatable.md)
- [EventSource](realitykit/eventsource.md)
- [HasCollision](realitykit/hascollision.md)
- [HasHierarchy](realitykit/hashierarchy.md)
- [HasSynchronization](realitykit/hassynchronization.md)
- [HasTransform](realitykit/hastransform.md)
- [Hashable](swift/hashable.md)
- [Identifiable](swift/identifiable.md)
- [Observable](observation/observable.md)
- [RealityCoordinateSpace](realitykit/realitycoordinatespace.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Collision shapes and groups

- [Simulating physics with collisions in your visionOS app](realitykit/simulating-physics-with-collisions-in-your-visionos-app.md)
- [Configuring Collision in RealityKit](realitykit/configuring-collision-in-realitykit.md)
- [Creating an interactive 3D model in visionOS](visionos/creating-an-interactable-3d-model-in-visionos.md)
- [CollisionComponent](realitykit/collisioncomponent.md)
- [CollisionComponent.Mode](realitykit/collisioncomponent/mode-swift.enum.md)
- [ShapeResource](realitykit/shaperesource.md)
- [ShapeResourceError](realitykit/shaperesourceerror.md)
- [CollisionGroup](realitykit/collisiongroup.md)
- [CollisionFilter](realitykit/collisionfilter.md)