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# isAlphaToOneEnabled

A Boolean value that indicates whether to force alpha channel values for color attachments to the largest representable value.

```
var isAlphaToOneEnabled: Bool { get set }
```

## Discussion

The default value is <doc://com.apple.documentation/documentation/Swift/false>.

If enabled, alpha channel fragment values are only forced for `colorAttachments[0]`. Other attachments are unaffected.

You may use `alphaToOneEnabled` when you want to write an alpha value that represents partial coverage of the pixel, but also want to disable blending (by forcing alpha to one).

---

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