# ParticlePhysicsExtensions

> Method extension for Physics in Particle System.

## Definition

* **Type:** Class
* **Namespace:** [UnityEngine](/engine/6000.7/script-reference/unityengine.md)
* **Assembly:** UnityEngine.ParticleSystemModule

```csharp
public static class ParticlePhysicsExtensions
```

## Static Methods

| Method                                                                                                                              | Description                                                                                                                                                                 |
| ----------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [GetCollisionEvents](/engine/6000.7/script-reference/unityengine/particlephysicsextensions/getcollisionevents.md)                   | Get the particle collision events for a GameObject. Returns the number of events written to the array.                                                                      |
| [GetSafeCollisionEventSize](/engine/6000.7/script-reference/unityengine/particlephysicsextensions/getsafecollisioneventsize.md)     | Safe array size for use with [ParticlePhysicsExtensions.GetCollisionEvents](/engine/6000.7/script-reference/unityengine/particlephysicsextensions/getcollisionevents.md).   |
| [GetSafeTriggerParticlesSize](/engine/6000.7/script-reference/unityengine/particlephysicsextensions/getsafetriggerparticlessize.md) | Safe array size for use with [ParticlePhysicsExtensions.GetTriggerParticles](/engine/6000.7/script-reference/unityengine/particlephysicsextensions/gettriggerparticles.md). |
| [GetTriggerParticles](/engine/6000.7/script-reference/unityengine/particlephysicsextensions/gettriggerparticles.md)                 | Get the particles that met the condition in the particle trigger module. Returns the number of particles written to the array.                                              |
| [SetTriggerParticles](/engine/6000.7/script-reference/unityengine/particlephysicsextensions/settriggerparticles.md)                 | Write modified particles back to the Particle System, during a call to OnParticleTrigger.                                                                                   |