public static float GetDPIScalingFactor()
{
Graphics g = Graphics.FromHwnd(IntPtr.Zero);
IntPtr desktop = g.GetHdc();
int LogicalScreenHeight = Gdi32Interop.GetDeviceCaps(desktop, (int)DeviceCap.VERTRES);
int PhysicalScreenHeight = Gdi32Interop.GetDeviceCaps(desktop, (int)DeviceCap.DESKTOPVERTRES);
float ScreenScalingFactor = (float)PhysicalScreenHeight / (float)LogicalScreenHeight;
return(ScreenScalingFactor);
}
/// <summary>
/// gamma range from 3 - 44
/// </summary>
/// <param name="gamma"></param>
private void SetGamma(int gamma)
{
_ramp.Red = new ushort[256];
_ramp.Green = new ushort[256];
_ramp.Blue = new ushort[256];
for (int i = 1; i < 256; i++)
{
_ramp.Red[i] = _ramp.Green[i] = _ramp.Blue[i]
= (ushort)Math.Min(
65535,
Math.Max(
0, (Math.Pow((i + 1) / 256.0, gamma * 0.1) * 65535 + 0.5)));
}
Gdi32Interop.SetDeviceGammaRamp(_hdc, ref _ramp);
}
