Hi all, Please consider donating to this or any of my many of opensource projects.

Kurecolor

A collection of tools aimed at those working with color, useful for CSS, Emacs themes, etc.

Use rainbow-mode when using kurecolor commands, for instant feedback on color changes.

Installing

Kurecolor is on MELPA, you can install using package.el

M-x package-install kurecolor

---

Color/hue range grouping

• kurecolor-hue-group (color &optional hue-groups)

Utility functions

• kurecolor-clamp (num min max)
• kurecolor-to-8bit (n)
• kurecolor-interpolate (color1 color2)

CSS helpers

• kurecolor-hex-to-cssrgb (hex)
• kurecolor-hex-to-cssrgba (hex)
• kurecolor-cssrgb-to-hex (cssrgb &optional hexrgba)
• kurecolor-css-rgb-value-to-number (value)

Absolute set hue, saturation, brightness

• kurecolor-hex-set-hue (hex hue)
• kurecolor-hex-set-saturation (hex sat)
• kurecolor-hex-set-brightness (hex val)

Set hue, saturation, brightness from another hex color

• kurecolor-hex-set-brightness-from (source target)
• kurecolor-hex-set-hue-from (source target)
• kurecolor-hex-set-saturation-from (source target)

RGB Hex to rgb

• kurecolor-hex-to-rgb (hex)

RGBA Hex to rgba

• kurecolor-hex-to-rgba (hex)

HSV/RGB/HEX (RGB) conversion

• kurecolor-hex-to-hsv (hex)
• kurecolor-hsv-to-hex (h s v)
• kurecolor-hsv-to-rgb (h s v)
• kurecolor-rgb-to-hex (rgb)

Get hue, saturation, brightness

• kurecolor-hex-get-brightness (hex)
• kurecolor-hex-get-saturation (hex)
• kurecolor-hex-get-hue (hex)

Color adjust

• kurecolor-adjust-saturation (hex amount)
• kurecolor-adjust-brightness (hex amount)
• kurecolor-adjust-hue (hex amount)

XCode color literal helpers

• kurecolor-hex-rgba-to-xcode-color-literal (rgba)
• kurecolor-xcode-literal-to-hex-rgba
• kurecolor-xcode-literal-to-hex-rgb

kurecolor-hue-group (color &optional hue-groups)

Return the color hue group for color.

Optionally provide a list of hue-groups, (default uses kurecolor-hue-groups.)

Also available is kurecolor-simple-hue-groups, both are customizable, or define your own.

This facilitates hue grouping & sorting by a secondary axis.

For example sort a list of colors by some axis (brightness or saturation). Then group by hue groups, and sort the groups.

The format of each group in the list is:

(group-name (n1 . n2))

Where group-name is a symbol to name the group, (n1 . n2) is a hue range specifier (in degrees) low n1 to high n2.

a hue range which crosses the apex (i.e. 360°..0°) is permitted.

(kurecolor-hue-group "#00FF00" '((group-a (340 . 120)) (group-b (120 . 240)) (group-c (240 . 340))))
 ⇒ 'group-b
(kurecolor-hue-group "#FFFF00" kurecolor-hue-groups)
 ⇒ 'yellow-green
(kurecolor-hue-group "#FF0000")
 ⇒ 'red

kurecolor-clamp (num min max)

Clamp num to range of min max.

(kurecolor-clamp 1 -1.0 1.0)
 ⇒ 1
(kurecolor-clamp 2 -1.0 1.0)
 ⇒ 1.0
(kurecolor-clamp -2 -1.0 1.0)
 ⇒ -1.0

kurecolor-to-8bit (n)

Convert n (0.0..1.0) to 0-255.

(kurecolor-to-8bit 0)
 ⇒ 0.0
(kurecolor-to-8bit 1)
 ⇒ 255.0
(kurecolor-to-8bit 0.3231)
 ⇒ 82.39

kurecolor-interpolate (color1 color2)

Interpolate two hex colors color1 and color2, to get their mixed color.

(kurecolor-interpolate "#FFFFFF" "#000000")
 ⇒ "#7F7F7F"
(kurecolor-interpolate "#0077FF" "#111111")
 ⇒ "#084488"
(kurecolor-interpolate "#FF7700" "#111111")
 ⇒ "#884408"

kurecolor-hex-to-cssrgb (hex)

Convert a hex rgb color to css rgb.

(kurecolor-hex-to-cssrgb "#347291")
 ⇒ "rgb(52, 114, 145)"
(kurecolor-hex-to-cssrgb "#000000")
 ⇒ "rgb(0, 0, 0)"
(kurecolor-hex-to-cssrgb "#888888")
 ⇒ "rgb(136, 136, 136)"

kurecolor-hex-to-cssrgba (hex)

Convert a hex rgba color to css rgba.

(kurecolor-hex-to-cssrgba "#347291FF")
 ⇒ "rgba(52, 114, 145, 1.0000)"
(kurecolor-hex-to-cssrgba "#34729100")
 ⇒ "rgba(52, 114, 145, 0.0000)"
(kurecolor-hex-to-cssrgba "#34729180")
 ⇒ "rgba(52, 114, 145, 0.5020)"

kurecolor-cssrgb-to-hex (cssrgb &optional hexrgba)

Convert a cssrgb (rgb() or rgba()) color to hex.

When hexrgba is non-nil the hex color string will be rgba. If css alpha value isn't present, it will be set as 1.0 i.e. no transparency

Valid css rgb() rgba() values are supported.

(kurecolor-cssrgb-to-hex "rgb(10%, 20%, 90%)")
 ⇒ "#1933E5"
(kurecolor-cssrgb-to-hex "rgba(100%, 100%, 100%, 1.0)")
 ⇒ "#FFFFFF"
(kurecolor-cssrgb-to-hex "rgb(52, 114, 145)")
 ⇒ "#347291"

kurecolor-css-rgb-value-to-number (value)

Convert css rgb() or rgba(): r, g, b value.

From number 0-255 or percentage, to 0-255.

(kurecolor-css-rgb-value-to-number "10")
 ⇒ 10
(kurecolor-css-rgb-value-to-number "10%")
 ⇒ 25.5
(kurecolor-css-rgb-value-to-number "100%")
 ⇒ 255.0

kurecolor-hex-set-hue (hex hue)

Change a hex color's hue, amount values from 0.0..1.0. returns a rgb hex color.

(kurecolor-hex-set-hue "#FF7700" 0.5)
 ⇒ "#00FFFF"
(kurecolor-hex-set-hue "#FF00FF" 0.5)
 ⇒ "#00FFFF"
(kurecolor-hex-set-hue "#FFFF00" 0.5)
 ⇒ "#00FFFF"

kurecolor-hex-set-saturation (hex sat)

Change a hex color's saturation sat, amount values from 0.0..1.0. returns a rgb hex color.

(kurecolor-hex-set-saturation "#FF7700" 0.5)
 ⇒ "#FFBB7F"
(kurecolor-hex-set-saturation "#007700" 0.5)
 ⇒ "#3B773B"
(kurecolor-hex-set-saturation "#FF0000" 0.5)
 ⇒ "#FF7F7F"

kurecolor-hex-set-brightness (hex val)

Change a hex color's brightness val, amount values from 0.0..1.0. returns a rgb hex color.

(kurecolor-hex-set-brightness "#FF7700" 0.5)
 ⇒ "#7F3B00"
(kurecolor-hex-set-brightness "#FF0000" 0.5)
 ⇒ "#7F0000"
(kurecolor-hex-set-brightness "#FF0077" 0.5)
 ⇒ "#7F003B"

kurecolor-hex-set-brightness-from (source target)

Copy brightness from source to target.

(kurecolor-hex-set-brightness-from "#008800" "#000000")
 ⇒ "#888888"
(kurecolor-hex-set-brightness-from "#00FF00" "#000000")
 ⇒ "#FFFFFF"
(kurecolor-hex-set-brightness-from "#000000" "#00FF00")
 ⇒ "#000000"

kurecolor-hex-set-hue-from (source target)

Copy brightness from source to target.

(kurecolor-hex-set-hue-from "#FF0000" "#00FF00")
 ⇒ "#FF0000"
(kurecolor-hex-set-hue-from "#00FF00" "#FF0000")
 ⇒ "#00FF00"
(kurecolor-hex-set-hue-from "#0088FF" "#880000")
 ⇒ "#004888"

kurecolor-hex-set-saturation-from (source target)

Copy the saturation of source to target.

(kurecolor-hex-set-saturation-from "#000000" "#00FF00")
 ⇒ "#FFFFFF"
(kurecolor-hex-set-saturation-from "#004400" "#00FF00")
 ⇒ "#00FF00"
(kurecolor-hex-set-saturation-from "#FFBB7F" "#FF7700")
 ⇒ "#FFBA7F"

kurecolor-hex-to-rgb (hex)

Convert a rgb hex color to a list (r g b).

The r,g,b values range between 0.0..1.0.

(kurecolor-hex-to-rgb "#347291")
 ⇒ '(0.2039 0.4471 0.5686)
(kurecolor-hex-to-rgb "#72FF91")
 ⇒ '(0.4471 1.0 0.5686)
(kurecolor-hex-to-rgb "#720091")
 ⇒ '(0.4471 0.0 0.5686)

kurecolor-hex-to-rgba (hex)

Convert a rgba hex color to a list (r g b a).

rgba hex colors = #rrggbbaa`` (i.e. css hex rgba)

e.g. #ffffff00`` white with no opacity. #000000FF black with no transparency.

The returned list (rgba) values will range between 0.0..1.0.

(kurecolor-hex-to-rgba "#34729100")
 ⇒ '(0.2039 0.4471 0.5686 0.0)
(kurecolor-hex-to-rgba "#FFFFFFFF")
 ⇒ '(1.0 1.0 1.0 1.0)
(kurecolor-hex-to-rgba "#72009172")
 ⇒ '(0.44715 0.0 0.5686 0.4471)

kurecolor-hex-to-hsv (hex)

Convert a rgb hex color to h s v.

(kurecolor-hex-to-hsv "#347291")
 ⇒ '(0.5556 0.6414 0.5686)
(kurecolor-hex-to-hsv "#729134")
 ⇒ '(0.2222 0.6414 0.5686)
(kurecolor-hex-to-hsv "#913472")
 ⇒ '(0.8889 0.6414 0.5686)

kurecolor-hsv-to-hex (h s v)

Convert h s v to a rgb hex color.

(kurecolor-hsv-to-hex 0.556 0.65 0.5687)
 ⇒ "#327191"
(kurecolor-hsv-to-hex 1.0 0.7 1.0)
 ⇒ "#FF4C4C"
(kurecolor-hsv-to-hex 0.5 0.5 0.6)
 ⇒ "#4C9999"

kurecolor-hsv-to-rgb (h s v)

Convert hsv (h s v) to red green blue. Note: args h s v are expected to be a values from 0.0..1.0

(kurecolor-hsv-to-rgb 0.5555 0.6413 0.5686)
 ⇒ '(0.2039 0.4472 0.5686)

kurecolor-rgb-to-hex (rgb)

rgb as a list (r g b) to rgb hex color.

The r,g,b values can range between 0.0..1.0.

(kurecolor-rgb-to-hex '(0.204 0.44706 0.5687))
 ⇒ "#347291"

kurecolor-hex-get-brightness (hex)

Get the brightness of hex color.

(kurecolor-hex-get-brightness "#FFFFFF")
 ⇒ 1.0
(kurecolor-hex-get-brightness "#808080")
 ⇒ 0.502
(kurecolor-hex-get-brightness "#000000")
 ⇒ 0.0

kurecolor-hex-get-saturation (hex)

Get the saturation of hex color.

(kurecolor-hex-get-saturation "#00FF00")
 ⇒ 1.0
(kurecolor-hex-get-saturation "#7FFF7F")
 ⇒ 0.502
(kurecolor-hex-get-saturation "#000000")
 ⇒ 0.0

kurecolor-hex-get-hue (hex)

Get the hue of hex color.

(kurecolor-hex-get-hue "#FF0000")
 ⇒ 0.0
(kurecolor-hex-get-hue "#00FF00")
 ⇒ 0.3333
(kurecolor-hex-get-hue "#0000FF")
 ⇒ 0.6667

kurecolor-adjust-saturation (hex amount)

Adjust the hex color saturation by amount -1.0..1.0.

(kurecolor-adjust-saturation "#006091" -0.1)
 ⇒ "#0E6491"
(kurecolor-adjust-saturation "#006091" -0.2)
 ⇒ "#1C6991"
(kurecolor-adjust-saturation "#006091" -0.5)
 ⇒ "#487891"

kurecolor-adjust-brightness (hex amount)

Adjust the hex color brightness by amount -1.0..1.0.

(kurecolor-adjust-brightness "#FFFFFF" -0.1)
 ⇒ "#E5E5E5"
(kurecolor-adjust-brightness "#FFFFFF" -0.2)
 ⇒ "#CCCCCC"
(kurecolor-adjust-brightness "#FFFFFF" -0.5)
 ⇒ "#7F7F7F"

kurecolor-adjust-hue (hex amount)

Adjust the hex color hue by amount 0.0..1.0.

(kurecolor-adjust-hue "#FF0000" -0.1)
 ⇒ "#FF0098"
(kurecolor-adjust-hue "#FF7700" -0.2)
 ⇒ "#FF00BB"
(kurecolor-adjust-hue "#FFFF00" -0.5)
 ⇒ "#0000FF"

kurecolor-hex-rgba-to-xcode-color-literal (rgba)

Convert a hex rgba string to an XCode colorLiteral.

(kurecolor-hex-rgba-to-xcode-color-literal "#0E1B21FF")
 ⇒ "#colorLiteral(red: 0.0549019608, green: 0.1058823529, blue: 0.1294117647, alpha: 1.0000000000)"
(kurecolor-hex-rgba-to-xcode-color-literal "#ECF3F600")
 ⇒ "#colorLiteral(red: 0.9254901961, green: 0.9529411765, blue: 0.9647058824, alpha: 0.0000000000)"
(kurecolor-hex-rgba-to-xcode-color-literal "#ADC3CC80")
 ⇒ "#colorLiteral(red: 0.6784313725, green: 0.7647058824, blue: 0.8000000000, alpha: 0.5019607843)"

kurecolor-xcode-literal-to-hex-rgba

(kurecolor-xcode-color-literal-to-hex-rgba "#colorLiteral(red: 0.0864074271, green: 0.1963072013, blue: 0.2599330357, alpha: 1)")
 ⇒ "#163242FF"
(kurecolor-xcode-color-literal-to-hex-rgba "#colorLiteral(red: 0.0585, green: 0.10855, blue: 0.13, alpha: 1)")
 ⇒ "#0E1B21FF"
(kurecolor-xcode-color-literal-to-hex-rgba "#colorLiteral(red: 0.9280523557, green: 0.9549868208, blue: 0.9678013393, alpha: 1)")
 ⇒ "#ECF3F6FF"

kurecolor-xcode-literal-to-hex-rgb

(kurecolor-xcode-color-literal-to-hex-rgb "#colorLiteral(red: 0.05882352941, green: 0.1098039216, blue: 0.0, alpha: 1)")
 ⇒ "#0E1C00"
(kurecolor-xcode-color-literal-to-hex-rgb "#colorLiteral(red: 0.0585, green: 0.10855, blue: 0.13, alpha: 1)")
 ⇒ "#0E1B21"
(kurecolor-xcode-color-literal-to-hex-rgb "#colorLiteral(red: 0.9280523557, green: 0.9549868208, blue: 0.9678013393, alpha: 1)")
 ⇒ "#ECF3F6"

Test/Examples

The examples documented here are live tests (in kurecolor-examples.el). You can run them using bin/test from the package folder.`

Ephemera

For those interested in such things, the name Kurecolor is unashamedly nicked from a high end marker pen company. Hopefully this outrage will fall silently under their radar, and I won't have to change it due to some frivilous and paranoid law suit. (seriously guys, this is just free advertising.)

I have not been pressured into saying this, however, Kurecolor markers and art supplies are the very best! Buy some (many!) NOW (Like REALLY Immediately!!) for you, your mum and your pet chinchilla Frank.

Since the question comes up occassionally, the mode-line hack used in the presentation is based on original work by Armit Patel. I gisted this a while back, you can get it from. https://gist.github.com/jasonm23/8554119