---
title: CGOpenGLDisplayMask
framework: coregraphics
role: symbol
role_heading: Type Alias
path: coregraphics/cgopengldisplaymask
---

# CGOpenGLDisplayMask

A bitmask used in OpenGL to specify a set of attached displays.

## Declaration

```swift
typealias CGOpenGLDisplayMask = UInt32
```

## Discussion

Discussion In macOS, OpenGL can provide information about the capabilities of the hardware renderers driving a specified set of displays. A 32-bit mask is used to specify the displays—each bit in the mask represents a single display. To learn how to find the mask bit that corresponds to a given display, see the function CGDisplayIDToOpenGLDisplayMask(_:).

## See Also

### Data Types

- [CGButtonCount](coregraphics/cgbuttoncount.md)
- [CGCharCode](coregraphics/cgcharcode.md)
- [CGDirectDisplayID](coregraphics/cgdirectdisplayid.md)
- [CGDisplayBlendFraction](coregraphics/cgdisplayblendfraction.md)
- [CGDisplayConfigRef](coregraphics/cgdisplayconfigref.md)
- [CGDisplayCount](coregraphics/cgdisplaycount.md)
- [CGDisplayErr](coregraphics/cgdisplayerr.md)
- [CGDisplayFadeInterval](coregraphics/cgdisplayfadeinterval.md)
- [CGDisplayFadeReservationToken](coregraphics/cgdisplayfadereservationtoken.md)
- [CGDisplayMode](coregraphics/cgdisplaymode.md)
- [CGDisplayReconfigurationCallBack](coregraphics/cgdisplayreconfigurationcallback.md)
- [CGDisplayReservationInterval](coregraphics/cgdisplayreservationinterval.md)
- [CGDisplayStream](coregraphics/cgdisplaystream.md)
- [CGDisplayStreamFrameAvailableHandler](coregraphics/cgdisplaystreamframeavailablehandler.md)
- [CGDisplayStreamUpdate](coregraphics/cgdisplaystreamupdate.md)