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# init(bounds:rate:distanceOffset:)

Creates a spatial force falloff.

```
init(bounds: ForceEffectBounds, rate: Double = 1.0, distanceOffset: Double = 0)
```

## Parameters

`bounds`

The spatial bounds used to compute the strength falloff.

`rate`

The rate at which the effect’s strength diminishes.

`distanceOffset`

The offset from the origin where fall begins.

## Discussion

- When the rate is **0**, no falloff occurs. (Rigid bodies outside the bounds are culled.)
- When the rate is **greater than 0 and less than 1.0**, falloff occurs slower and is sublinear.
- When the rate is **1.0**, falloff is linear.
- When the rate is **greater than 1**, falloff occurs faster and is nonlinear.

---

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