P°evod RGB na HSL
Public Type HSL
Hue As Integer
Saturation As Integer
Luminance As Integer
End Type
Public Function RGBtoHSL(ByVal Red As Integer, _
ByVal Green As Integer, _
ByVal Blue As Integer) As HSL
Dim pRed As Single
Dim pGreen As Single
Dim pBlue As Single
Dim RetVal As HSL
Dim pMax As Single
Dim pMin As Single
Dim pLum As Single
Dim pSat As Single
Dim pHue As Single
pRed = Red / 255
pGreen = Green / 255
pBlue = Blue / 255
If pRed > pGreen Then
If pRed > pBlue Then
pMax = pRed
Else
pMax = pBlue
End If
ElseIf pGreen > pBlue Then
pMax = pGreen
Else
pMax = pBlue
End If
If pRed < pGreen Then
If pRed < pBlue Then
pMin = pRed
Else
pMin = pBlue
End If
ElseIf pGreen < pBlue Then
pMin = pGreen
Else
pMin = pBlue
End If
pLum = (pMax + pMin) / 2
If pMax = pMin Then
pSat = 0
pHue = 0
Else
If pLum < 0.5 Then
pSat = (pMax - pMin) / (pMax + pMin)
Else
pSat = (pMax - pMin) / (2 - pMax - pMin)
End If
Select Case pMax!
Case pRed
pHue = (pGreen - pBlue) / (pMax - pMin)
Case pGreen
pHue = 2 + (pBlue - pRed) / (pMax - pMin)
Case pBlue
pHue = 4 + (pRed - pGreen) / (pMax - pMin)
End Select
End If
RetVal.Hue = pHue * 239 \ 6
If RetVal.Hue < 0 Then RetVal.Hue = RetVal.Hue + 240
RetVal.Saturation = Int(pSat * 239)
RetVal.Luminance = Int(pLum * 239)
RGBtoHSL = RetVal
End Function