Screen name identifier for multiple screens scenarios (Screen numbering on Windows is not reliable)

[PippoApps]

I have several installations running requiring 3 or more screens attached to the same machine.
Whilst AIR handles multi-screen setups perfectly, there is no precise way to detect via code which screen number corresponds to the physical screen. Windows on restart often changes screen numbering. Or, there are scenarios where the installations stays powered on at night, but tmain projector is off. Punctually, when the projector is powered on, or at a machine restart, windows reassigns screen numbering, that gets reflected in the AIR app, messing up the setup and focing to cumbersome remote operations.

Although it is possible to access the "primary screen" flag, on setups with 3+ screens it is not enough.

Windows has access to a screen name, and several third party apps also do, so I believe there is no limitation in providing the Screen class in ActionScript access to the screen name. This would be a game changer when powering up or maintaining remote installations built in AIR that require multiple screens.

[itlancer]

Essential function. Maybe we need to have a way to get GUID of monitor. Or maybe get native screen object via native extension similar to FRENativeWindow and get work with that as application logic needed.

[PippoApps]

It seems that information is available to other applications even without admin privileges.

[PippoApps]

Or it could rely not on the monitor numbering but on the GPU port id...

[ajwfrost]

Hi all

Attached is a zip of an ANE that will do this, plus a couple other utilities..

Class to create is com.harman.extension.WindowsScreen and the methods available are then:

• getScreenName(scrn : Screen) : String - the name per that "\.\DISPLAY1" type format.
• getMonitorGUID(scrn : Screen) : uint - the GUID (it's meant to be a handle type on Windows, but even on 64-bit Windows it seems only the bottom 32 bits are used..)
• getNativeWindowPositionInVirtualScreenCoordinates(wnd : NativeWindow) : Rectangle - to get the window rectangle in virtual/global desktop coordinates (i.e. ignores scaling and assumes monitors are laid out per your Settings with the primary monitor at (0,0))
• setNativeWindowPositionInVirtualScreenCoordinates(wnd: NativeWindow, pos:Rectangle) : void - sets it using the same mechanism.
• moveNativeWindowToScreen(wnd : NativeWindow, scrn : Screen, unscaledPos : Rectangle = null) : void - moves a window to a new screen, either leaving the size alone or using the given rectangle (in unscaled coordinates so giving the monitor resolution would result in a full-screen view)
• getScreensForNativeWindow(wnd : NativeWindow) : Array - provide an array containing all the screens that the window is present on, with it's default screen being the first in the list. If the window isn't on a screen then it returns null.

Let us know of any issues/comments! It might be that we put some of this functionality into the AIR core AS3 API at some point if it seems like this would be useful for other platforms too; right now this is just for Windows.

thanks

Andrew
WindowsScreen.ane.zip

[PippoApps]

Thank you Andrew, it works beautifully.
As far as I can see, GUID should remain consistent on system restarts right?
It would be great to have it as a core feature in AIR.
Even better, being able to read screen manufacturer and model (apparently it is doable on windows)
Cheers

[ajwfrost]

Yes I'm 99% sure the GUID is always the same..
I can check whether the same sorts of capabilities could be implemented on macOS (and possibly Linux) which would mean we could then consider it for core functionality..

[PippoApps]

Thank you, Andrew; that would be fantastic allowing air as a suitable solution for museum installations. If you also implement NDI video transmission, then it would again be a game changer, competing with TouchDesigner but more robust and code-oriented. I am willing to advocate for AIR as a viable solution for installations and performances in contemporary art through conferences and speeches, but NDI and screen consistency are a must. (So far I mostly use a virtual display driver and OBS capture with NDI transmission, but it is complex to restart in a museum/exhibition context). Cheers for your help! The ane makes it usable at least for me!