---
title: NSCompositingOperation.plusDarker
framework: appkit
role: symbol
role_heading: Case
path: appkit/nscompositingoperation/plusdarker
---

# NSCompositingOperation.plusDarker

The sum of the source and destination images, with color values approach 0 as a limit.

## Declaration

```swift
case plusDarker
```

## Discussion

Discussion The source image is applied using the formula R = MAX(0, (1 - D) + (1 - S)).

## See Also

### Operations for Compositing

- [NSCompositingOperation.clear](appkit/nscompositingoperation/clear.md)
- [NSCompositingOperation.copy](appkit/nscompositingoperation/copy.md)
- [NSCompositingOperation.sourceOver](appkit/nscompositingoperation/sourceover.md)
- [NSCompositingOperation.sourceIn](appkit/nscompositingoperation/sourcein.md)
- [NSCompositingOperation.sourceOut](appkit/nscompositingoperation/sourceout.md)
- [NSCompositingOperation.sourceAtop](appkit/nscompositingoperation/sourceatop.md)
- [NSCompositingOperation.destinationOver](appkit/nscompositingoperation/destinationover.md)
- [NSCompositingOperation.destinationIn](appkit/nscompositingoperation/destinationin.md)
- [NSCompositingOperation.destinationOut](appkit/nscompositingoperation/destinationout.md)
- [NSCompositingOperation.destinationAtop](appkit/nscompositingoperation/destinationatop.md)
- [NSCompositingOperation.xor](appkit/nscompositingoperation/xor.md)
- [NSCompositingOperation.plusLighter](appkit/nscompositingoperation/pluslighter.md)
- [NSCompositingOperation.multiply](appkit/nscompositingoperation/multiply.md)
- [NSCompositingOperation.screen](appkit/nscompositingoperation/screen.md)
- [NSCompositingOperation.overlay](appkit/nscompositingoperation/overlay.md)