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# openGLContext()

Returns the OpenGL context used by the view.

```
func openGLContext() -> NSOpenGLContext!
```

## Return Value

An `NSOpenGLContext` object.

## Discussion

This context as a read-only object . Do not attempt to change any of its settings. If you subclass `QCView` so that you can perform custom OpenGL drawing, you’ll need to use this method to retrieve the view’s OpenGL context.

## See Also

[`render(atTime:arguments:)`](/documentation/Quartz/QCView/render(atTime:arguments:))

Overrides to perform  your custom operations prior to or after rendering a frame of a composition.


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