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# MTLStencilOperation

The operation performed on a currently stored stencil value when a comparison test passes or fails.

```
enum MTLStencilOperation
```

## Topics

### Stencil operations

[`MTLStencilOperation.keep`](/documentation/Metal/MTLStencilOperation/keep)

A stencil operation that doesn’t modify a stencil value.

[`MTLStencilOperation.zero`](/documentation/Metal/MTLStencilOperation/zero)

A stencil operation that sets a stencil value to zero.

[`MTLStencilOperation.replace`](/documentation/Metal/MTLStencilOperation/replace)

A stencil operation that replaces a stencil value with a reference value.

[`MTLStencilOperation.incrementClamp`](/documentation/Metal/MTLStencilOperation/incrementClamp)

A stencil operation that increases a stencil value by one, but only when
the current value isn’t the maximum representable value.

[`MTLStencilOperation.decrementClamp`](/documentation/Metal/MTLStencilOperation/decrementClamp)

A stencil operation that decreases a nonzero stencil value by one.

[`MTLStencilOperation.invert`](/documentation/Metal/MTLStencilOperation/invert)

A stencil operation that applies a logical bitwise NOT to a stencil value.

[`MTLStencilOperation.incrementWrap`](/documentation/Metal/MTLStencilOperation/incrementWrap)

A stencil operation that decreases a nonzero stencil value by one,
or when it’s the maximum representable value, resets it to zero.

[`MTLStencilOperation.decrementWrap`](/documentation/Metal/MTLStencilOperation/decrementWrap)

A stencil operation that decreases a nonzero stencil value by one,
or when it’s zero, resets it to the maximum representable value.


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