RGB to HEX convert script

[Daniel]

OK bit of calculation is needed. Here is script which converts 3B RGB in to RGBW and saturation. You could convert it to your needs.

Code:

addressred = '1/1/16' addressgreen = '1/1/17' addressblue = '1/1/18' addresswhite = '1/1/19' addresssaturation = '1/1/20' -- Get Value of RGB picker value = event.getvalue() -- Convert to HEX for splitting to 3 byte values value = lmcore.inttohex(value, 3) -- 3 = number of bytes inside value -- Split First 2 byte HEX values from 3 byte HEX redandgreen = string.sub(value, 1, 4) -- Split First Value from 2 byte HEX red = string.sub(redandgreen, 1, 2) -- Split Last value from 2 byte HEX green = string.sub(redandgreen, -2) -- Split Last byte value from 3 byte HEX blue = string.sub(value, -2) -- Convert HEX values back to integer valuered = lmcore.hextoint (red) valuegreen = lmcore.hextoint (green) valueblue = lmcore.hextoint (blue) -- Calculate lowest value of RGB value low = math.min(unpack({valuered, valuegreen, valueblue})) -- Calculate highest value of RGB value high = math.max(unpack({valuered, valuegreen, valueblue})) -- Calculate Saturation (The saturation is the colorfulness of a color relative to its own brightness) The difference between the last two variables divided by the highest is the saturation. saturation = math.floor((100 * ((high - low) / high)) + 0.5) if valuered == 0 and valuegreen == 0 and valueblue == 0 then  white = 0 else  white = math.floor(((255 - saturation) / 255 * (valuered + valuegreen + valueblue) / 3)+ 0.5) end -- Write integer RGB values and Calculated White & Saturation to KNX grp.update(addressred, math.floor((valuered / 2.55) + 0.5)) grp.update(addressgreen, math.floor((valuegreen / 2.55) + 0.5)) grp.update(addressblue, math.floor((valueblue / 2.55) + 0.5)) grp.update(addresswhite, math.floor((white / 2.55) + 0.5)) grp.update(addresssaturation, saturation)

BR