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HSL.ToHex

Converts HSL color values to hexadecimal format

EvaluationContext.Colour.HSL.ToHex( h, s, l, alpha )
Parameter Type Required Description
h INT64 Hue (0-360)
s DOUBLE Saturation (0-1)
l DOUBLE Lightness (0-1)
alpha DOUBLE The alpha value (0-1)

STRING Hex color string with optional alpha

EvaluationContext.Colour.HSL.ToHex(0, 1, 0.5) // Returns "#FF0000"

function 'EvaluationContext.Colour.HSL.ToHex' =
        (
            h: INT64,
            s: DOUBLE,
            l: DOUBLE,
            alpha: DOUBLE
        ) =>

            VAR C = ( 1 - ABS(2 * l - 1 ) ) * s
            VAR X = C * ( 1 - ABS( MOD( H / 60, 2 ) - 1 ) )
            VAR M = l - C / 2

            VAR RGB1 = SWITCH(
                true,
                h < 60, C & "," & X & ",0",
                h < 120, X & "," & C & ",0",
                h < 180, "0," & C & "," & X,
                h < 240, "0," & X & "," & C,
                h < 300, X & ",0," & C,
                C & ",0," & X
            )

            VAR RPrime =        VALUE( LEFT( RGB1, SEARCH(",", RGB1 ) - 1 ) )
            VAR Remaining =     RIGHT( RGB1, LEN( RGB1 ) - SEARCH( ",", RGB1 ) )
            VAR GPrime =        VALUE( LEFT( Remaining, SEARCH( ",", Remaining ) - 1) )
            VAR BPrime =        VALUE( RIGHT( Remaining, LEN( Remaining ) - SEARCH( ",", Remaining ) ) )

            VAR FinalR =        ROUND( ( RPrime + M) * 255, 0)
            VAR FinalG =        ROUND( ( GPrime + M) * 255, 0)
            VAR FinalB =        ROUND( ( BPrime + M) * 255, 0)

            VAR result =
                "#" &
                EvaluationContext.Colour.Int.ToHex(FinalR, 2) &
                EvaluationContext.Colour.Int.ToHex(FinalG, 2) &
                EvaluationContext.Colour.Int.ToHex(FinalB, 2) &
                IF( NOT ISBLANK( alpha ), EvaluationContext.Colour.Int.ToHex( alpha * 255, 2 ) )

            RETURN result