How to convert the position in CGDisplayBounds() to global coordinate ( like NSEvent.mouseLocation) in Swift

I'm a newbie in Swift and MacOS.
I gonna find a method to get the exact display coordinate

NSEvent.mouseLocation

I have found method in CoreGraphic :

func CGDisplayBounds(_ display: CGDirectDisplayID) -> CGRect

but the coordinate is different.

I can workaround to apply a method to mathematically method to convert point Y.
But is there any method to get or convert the position programmatically?

I expect to get the same coordinate with NSEvent.mouseLocation.

Thank for your attention.

It returns to the same coordinate with mouse location.

As you noted, CoreGraphics has what Apple calls ‘flipped’ geometry, with the origin at the top left and the y coordinates increasing toward the bottom of the screen. This is the geometry used by most computer graphics systems.

AppKit prefers what Apple calls ‘non-flipped’, with the origin at the bottom left and the y coordinates increasing toward the top of the screen. This is the geometry normally used in mathematics.

The origin (0, 0) of the CoreGraphics global geometry is always at the top-left of the ‘main’ display (identified by CGMainDisplayID()). The origin of the AppKit global geometry is always at the bottom-left of the main display. To convert between the two geometries, subtract your y coordinate from the height of the main display.

That is:

extension CGPoint {
    func convertedToAppKit() -> CGPoint {
        return .init(
            x: x,
            y: CGDisplayBounds(CGMainDisplayID()).height - y
        )
    }

    func convertedToCoreGraphics() -> CGPoint {
        return .init(
            x: x,
            y: CGDisplayBounds(CGMainDisplayID()).height - y
        )
    }
}

You may notice that these two functions have the same implementation. You don't really need two functions; you can just use one. It converts in both directions.

Calling CGDisplayBounds(CGMainDisplayID()) might also be inefficient. You might want to cache the value or batch your transformations if you're going to be doing a lot of them. But if you cache the value, you'll want to subscribe to NSApplication.didChangeScreenParametersNotification so you can update the cached value if it needs to change.