Values in resizeOverlay not coherent with values in showOverlay about flutter_overlay_window

[jglatre]

Looking source code of OverlayService I see you are applying dpToPx to parameters of resizeOverlay buy not applying it to parameters of showOverlay. I hope that will be a hint.

[rorystephenson]

The initial width/height does not take in to account the display metrics whilst resizeOverlay does. A workaround is to apply the display metrics yourself when setting the initial width/height by multiplying your desired size by MediaQuery.devicePixelRatioOf(context). The result is not exactly identical as there seems to be a rounding difference but it should be within 1px.

EDIT: The rounding difference is avoidable. The resizeOverlay method applies the display metrics and then truncates (drops the decimal) the resulting width/height since it needs to be specified as an int. My setting of the initial width/height was rounding up to make sure I have at least as much space as I ask for. Two options to get a more consistent size:

1. When applying the device pixel ratio to the original width/height, round down. This can result in a slightly lower size than desired.
2. When calling resizeOverlay we can round up the width/height so that when it is multiplied by the device pixel ratio and then truncated it will be at least as large as our desired width/height. Unfortunately since the arguments to resizeOverlay are ints we cannot totally avoid unnecessary rounding up (without modifying the package). Here is an example method:

  static Future<bool?> resizeOverlay(BuildContext context, Size size) {
    final devicePixelRatio = MediaQuery.devicePixelRatioOf(context);

    final adjustedWidth =
        (((size.width * devicePixelRatio).ceilToDouble()) / devicePixelRatio)
            .ceil();
    final adjustedHeight =
        (((size.height * devicePixelRatio).ceilToDouble()) / devicePixelRatio)
            .ceil();

    return FlutterOverlayWindow.resizeOverlay(adjustedWidth, adjustedHeight);
  }

[Ahmadu-Suleiman]

Why was resizeOverlay written that way, seems unnecessary to me. Can someone explain pls?