---
title: isAlphaToOneEnabled
framework: metal
role: symbol
role_heading: Instance Property
path: metal/mtlrenderpipelinedescriptor/isalphatooneenabled
---

# isAlphaToOneEnabled

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

## Declaration

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

## Discussion

Discussion The default value is 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).

## See Also

### Specifying rasterization and visibility state

- [isAlphaToCoverageEnabled](metal/mtlrenderpipelinedescriptor/isalphatocoverageenabled.md)
- [isRasterizationEnabled](metal/mtlrenderpipelinedescriptor/israsterizationenabled.md)
- [inputPrimitiveTopology](metal/mtlrenderpipelinedescriptor/inputprimitivetopology.md)
- [rasterSampleCount](metal/mtlrenderpipelinedescriptor/rastersamplecount.md)
- [MTLPrimitiveTopologyClass](metal/mtlprimitivetopologyclass.md)
- [sampleCount](metal/mtlrenderpipelinedescriptor/samplecount.md)