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# rate

The spatial falloff / attenuation rate.

```
var rate: Double
```

## Discussion

An exponent that determines how the effect’s strength diminishes with distance. Use a non-negative rate.

- When the rate is **0**, no falloff occurs.
- 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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