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# depthCompareFunction

The comparison that is performed between a fragment’s depth value and the depth value in the attachment, which determines whether to discard the fragment.

```
var depthCompareFunction: MTLCompareFunction { get set }
```

## Discussion

The default value is [`MTLCompareFunction.always`](/documentation/Metal/MTLCompareFunction/always), which indicates that the depth test always passes and the fragment remains a candidate to replace the data at the specified location. For more information on possible values, see [`MTLCompareFunction`](/documentation/Metal/MTLCompareFunction).

## See Also

  [Metal Shading Language Guide](https://developer.apple.com/library/archive/documentation/Metal/Reference/MetalShadingLanguageGuide/Introduction/Introduction.html#//apple_ref/doc/uid/TP40014364)

  [Metal Programming Guide](https://developer.apple.com/library/archive/documentation/Miscellaneous/Conceptual/MetalProgrammingGuide/Introduction/Introduction.html#//apple_ref/doc/uid/TP40014221)


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