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# setObject:atIndexedSubscript:

Sets the render pipeline state for a specified color attachment.

```
- (void) setObject:(MTLRenderPipelineColorAttachmentDescriptor *) attachment atIndexedSubscript:(NSUInteger) attachmentIndex;
```

## Parameters

`attachment`

A descriptor that contains the render pipeline description for a color attachment.

`attachmentIndex`

An index in the color attachment array.

## Discussion

This method copies the pipeline state from the descriptor into the specified attachment in the array. The descriptor passed into this method can be modified and reused without affecting a previously set attachment.

If this method is called with `nil` for `attachment` for any legal index, its attachment descriptor state is set to the default values.

---

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