Powershell script to convert HSL to RGB

ConvertFrom-Hsl.ps1

function ConvertFrom-Hsl {
    param(
        $Hue,
        $Saturation,
        $Lightness, 
        # Return in ConEmu.xml ABGR hex format
        [Switch]$ABGR
    )
    
    function ToHex ($c) {
        $hex = [Convert]::ToString([Math]::Round($c * 255), 16).ToUpper()
        if ($hex.Length -eq 1) {
            "0$hex"
        } else {
            "$hex"
        }
    }

    $Hue = [double]($Hue / 360)
    if ($Saturation -gt 1) {
        $Saturation = [double]($Saturation / 100)
    }
    if ($Lightness -gt 1) {
        $Lightness = [double]($Lightness / 100)
    }
    
    if ($Saturation -eq 0) {
        # No color
        $red = $green = $blue = $Lightness
    } else {
        function HueToRgb ($p,$q,$t) {
            if ($t -lt 0) {
                $t++
            }
            if ($t -gt 1) {
                $t--
            } 
            if ($t -lt 1/6) {
                return $p + ($q - $p) * 6 * $t
            } 
            if ($t -lt 1/2) {
                return $q
            }
            if ($t -lt 2/3) {
                return $p + ($q - $p) * (2/3 - $t) * 6
            }
            return $p
        }
        $q = if ($Lightness -lt .5) {
            $Lightness * (1 + $Saturation)
        } else {
            $Lightness + $Saturation - $Lightness * $Saturation
        }
        $p = 2 * $Lightness - $q
        $red = HueToRgb $p $q ($Hue + 1/3)
        $green = HueToRgb $p $q $Hue
        $blue = HueToRgb $p $q ($Hue - 1/3)
    }
    
    if ($ABGR) {
        $b = ToHex $blue
        $g = ToHex $green
        $r = Tohex $red
        "$b$g$r"
    } else {
        [Ordered]@{
            Red = [Math]::Round($red * 255)
            Green = [Math]::Round($green * 255)
            Blue = [Math]::Round($blue * 255)
        }
    }
}