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# setFlatness(_:)

Sets the accuracy of curved paths in a graphics context.

```
func setFlatness(_ flatness: CGFloat)
```

## Parameters

`flatness`

The largest permissible distance, measured in device pixels, between a point on the true curve and a point on the approximated curve.

## Discussion

This function controls how accurately curved paths are rendered. Setting the flatness value to less than `1.0` renders highly accurate curves, but lengthens rendering times.

In most cases, you should not change the flatness value. Customizing the flatness value for the capabilities of a particular output device impairs the ability of your application to render to other devices.

---

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