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# setCachedSeparately:

Sets whether each image representation uses a separate offscreen window to cache its contents.

```
- (void) setCachedSeparately:(BOOL) flag;
```

## Parameters

`flag`

<doc://com.apple.documentation/documentation/Swift/true> if you want each of the receiver’s image representation objects to use a separate offscreen window for caching; otherwise, <doc://com.apple.documentation/documentation/Swift/false>.

## Discussion

If you specify <doc://com.apple.documentation/documentation/Swift/false>, a representation can be cached together with other images, though in practice it might not be. This method does not invalidate any existing caches.

If you plan to resize an `NSImage` object frequently, it is usually more efficient to cache its representations separately. In some situations, you might also want to enable separate caching if you plan to use the [`compositeToPoint:fromRect:operation:`](/documentation/AppKit/NSImage/compositeToPoint:fromRect:operation:) or [`compositeToPoint:fromRect:operation:fraction:`](/documentation/AppKit/NSImage/compositeToPoint:fromRect:operation:fraction:)methods to draw the image.

## See Also

[`func recache()`](/documentation/AppKit/NSImage/recache())

Invalidates and frees offscreen caches of all image representations.


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