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# setStrokeColor(gray:alpha:)

Sets the current stroke color to a value in the DeviceGray color space.

```
func setStrokeColor(gray: CGFloat, alpha: CGFloat)
```

## Parameters

`gray`

A value that specifies the desired gray level. The DeviceGray color space permits the specification of a value ranging from `0.0` (absolute black) to `1.0` (absolute white). Values outside this range are clamped to `0.0` or `1.0`.

`alpha`

A value that specifies the opacity level. Values can range from `0.0` (transparent) to `1.0` (opaque). Values outside this range are clipped to `0.0` or `1.0`.

## Discussion

When you call this function, two things happen:

- Core Graphics sets the current stroke color space to DeviceGray. The DeviceGray color space is a single-dimension space in which color values are specified solely by the intensity of a gray value (from absolute black to absolute white).
- Core Graphics sets the current stroke color to the value you specify in the `gray` and `alpha` parameters.

---

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