---
title: isAffectedByPhysicsFields
framework: scenekit
role: symbol
role_heading: Instance Property
path: scenekit/scnparticlesystem/isaffectedbyphysicsfields
---

# isAffectedByPhysicsFields

A Boolean value that determines whether physics fields in the scene affect the motion of particles.

## Declaration

```swift
var isAffectedByPhysicsFields: Bool { get set }
```

## Discussion

Discussion SCNPhysicsField objects attached to nodes in the scene apply forces to bodies in their area of effect. For example, a radial gravity field attracts bodies toward its center, and a vortex field applies forces that circulate around a specified axis. The forces applied by a physics field on each particle are proportional to its mass, as specified by the particleMass property. The default value is false, specifying that physics fields in the scene do not affect particles.

## See Also

### Simulating Physics for Particles

- [isAffectedByGravity](scenekit/scnparticlesystem/isaffectedbygravity.md)
- [colliderNodes](scenekit/scnparticlesystem/collidernodes.md)
- [particleDiesOnCollision](scenekit/scnparticlesystem/particlediesoncollision.md)
- [acceleration](scenekit/scnparticlesystem/acceleration.md)
- [dampingFactor](scenekit/scnparticlesystem/dampingfactor.md)
- [particleMass](scenekit/scnparticlesystem/particlemass.md)
- [particleMassVariation](scenekit/scnparticlesystem/particlemassvariation.md)
- [particleCharge](scenekit/scnparticlesystem/particlecharge.md)
- [particleChargeVariation](scenekit/scnparticlesystem/particlechargevariation.md)
- [particleBounce](scenekit/scnparticlesystem/particlebounce.md)
- [particleBounceVariation](scenekit/scnparticlesystem/particlebouncevariation.md)
- [particleFriction](scenekit/scnparticlesystem/particlefriction.md)
- [particleFrictionVariation](scenekit/scnparticlesystem/particlefrictionvariation.md)