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# stiffness

The stiffness by which the particle is pulled towards the position.

```
var stiffness: Float { get set }
```

## Discussion

In the context of a target shape, this gets multiplied by the weight of the target shape.
A stiffness of 0 will effectively inactivate the position constraint.

The valid range is [0.0, 1.0], both included. Values outside the valid range are clamped.

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