private float CalcScale()
{
using (var g = Graphics.FromHwnd(IntPtr.Zero))
{
IntPtr desktop = g.GetHdc();
int logicalScreenHeight = WindowNative.GetDeviceCaps(desktop, (int)WindowNative.DeviceCap.VERTRES);
int physicalScreenHeight = WindowNative.GetDeviceCaps(desktop, (int)WindowNative.DeviceCap.DESKTOPVERTRES);
return((float)physicalScreenHeight / logicalScreenHeight);
}
}