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RGB to HEX convert script

I have LED Dali strip, which I can set RGB values to. I wanted to use a mosaic widget to set color value but it only works with HEX code. I have three seperate group adresses (r, g, b) and I need to convert them to one HEX group address that I can link to that widget. Is this possible?

EDIT: First question has been solved, sorry I did some deeper research and found whole article.

A completely different question. Is is possible to DIM pre-mixed RGB color? Let's say I also have 3 group adresses, which I mixed and got my final color. I now want to dim it so it's the same color but less bright.

Thanks for any help.
If you didn't use yet then select RGBW widget.
To dim just use the slider.
Thank you very much! Haven't tried that yet but if it works, is there a way to automatize it? I only need a single switch group that switches on already mixed and dimmed RGB strip.
(16.05.2018, 09:04)Jayce Wrote: Thank you very much! Haven't tried that yet but if it works, is there a way to automatize it? I only need a single switch group that switches on already mixed and dimmed RGB strip.

Sorry don't know what you mean by that.
I forgot to mention that the second question was outside of mosaic. Let me explain myself better. Right now, I have created a group (let's call it RGB), where I put a simple script that sets three groups (red, green and blue) to certain value. That means when I set RGB group to 1, my exact color mixture turns on. The problem is it is too bright. I need to dim it. As you said, I might be able to dim it with RGBW widget, but that is widget. I'd need it to be outside of mosaic.
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.

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
 white = math.floor(((255 - saturation) / 255 * (valuered + valuegreen + valueblue) / 3)+ 0.5)

-- 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)
Works, thank you a lot.

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