# ParticleSystem.ExternalForcesModule

> Script interface for the ExternalForcesModule of a Particle System.

## Definition

* **Type:** Struct
* **Namespace:** [UnityEngine](/engine/6000.6/script-reference/unityengine.md)
* **Assembly:** UnityEngine.ParticleSystemModule

```csharp
public struct ParticleSystem.ExternalForcesModule
```

## Remarks

Additional Resources: [ParticleSystem](/engine/6000.6/script-reference/unityengine/particlesystem.md), [ParticleSystem.externalForces](/engine/6000.6/script-reference/unityengine/particlesystem/externalforces.md).

## Properties

| Property                                                                                                              | Description                                                                               |
| --------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------- |
| [enabled](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/enabled.md)                 | Specifies whether the ExternalForcesModule is enabled or disabled.                        |
| [influenceCount](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/influencecount.md)   | The number of Force Fields explicitly provided to the influencers list.                   |
| [influenceFilter](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/influencefilter.md) | Apply all Force Fields belonging to a matching Layer to this Particle System.             |
| [influenceMask](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/influencemask.md)     | Particle System Force Field Components with a matching Layer affect this Particle System. |
| [multiplier](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/multiplier.md)           | Multiplies the magnitude of external forces affecting the particles.                      |
| [multiplierCurve](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/multipliercurve.md) | Multiplies the magnitude of applied external forces.                                      |

## Methods

| Method                                                                                                                        | Description                                                                                                                                              |
| ----------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [AddInfluence](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/addinfluence.md)               | Adds a [ParticleSystemForceField](/engine/6000.6/script-reference/unityengine/particlesystemforcefield.md) to the influencers list.                      |
| [GetInfluence](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/getinfluence.md)               | Gets the [ParticleSystemForceField](/engine/6000.6/script-reference/unityengine/particlesystemforcefield.md) at the given index in the influencers list. |
| [IsAffectedBy](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/isaffectedby.md)               | Determines whether any particles are inside the influence of a Force Field.                                                                              |
| [RemoveAllInfluences](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/removeallinfluences.md) | Removes every Force Field from the influencers list.                                                                                                     |
| [RemoveInfluence](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/removeinfluence.md)         | Removes the Force Field from the influencers list at the given index.                                                                                    |
| [SetInfluence](/engine/6000.6/script-reference/unityengine/particlesystem/externalforcesmodule/setinfluence.md)               | Assigns the Force Field at the given index in the influencers list.                                                                                      |