Command/definecolor

Summary

The command \definecolor is used to create or copy a named color.

Settings

\definecolor[...][...=...,...]
[...]	name
r	number
g	number
b	number
c	number
m	number
y	number
k	number
h	number
s	number
v	number
w	number
x	number
a	number none normal multiply screen overlay softlight hardlight colordodge colorburn darken lighten difference exclusion hue saturation color luminosity
t	number

Option Explanation

color name, must not contain spaces or numbers

r

RGB red channel (0–1)

g

RGB green channel (0–1)

b

RGB blue channel (0–1), HWB blackness (0–1)

c

CMYK cyan channel (0–1)

m

CMYK magenta channel (0–1)

y

CMYK yellow channel (0–1)

k

CMYK black channel (0–1)

h

HSV or HWB hue degree (0–360)

s

Grayscale black value (0–1), HSV saturation (0–1)

v

HSV value (0–1)

w

HWB whiteness (0–1)

x

RGB hex value (as in HTML/CSS)

a

transparency mode (“alternative”), see Transparency and the color manual. You can use the number or the name of a mode.
number	mode number
none	no transparency
normal	also no transparency
multiply	colors get darker
screen	multiply negatively, colors get lighter
overlay	copy together: mixture of `multiply` and `screen`, increases contrast
softlight	milder version of `overlay`
hardlight	more intense version of `overlay`
colordodge	similar to `screen`, makes lights lighter and increases contrast
colorburn	similar to `multiply`, increases intensity and contrast
darken	use the darker of two colors
lighten	use the lighter of two colors
difference	same values become black, other colors get inverted
exclusion	similar to `difference`, but more matte
hue	upper layer defines the hue, saturation and lightness stay
saturation	upper layer defines the saturation, hue and lightness stay
color	upper layer defines the hue, luminosity stays; good for coloration
luminosity	upper layer defines the luminosity, hue stays

t

transparency value (0–1) – actually, opacity: 1 is opaque, 0 is invisibly transparent

Settings name

\definecolor[...][...]
[...]	name
[...]	color

Option	Explanation
new name
original (parent) name

Description

\definecolor associates a name with a set of color values, for later use with the \color command.

You can omit 0 values.

Examples

Normal usage

% rgb
\definecolor[bluu][r=.25, g=.1, b=1]
Hey, \color[bluu]{look at that!}

% hex
\definecolor[salmon][x=AB5757]
Hey, \color[salmon]{look at that!}

\definecolor[brightorange][c=0, m=.4325, y=.9286, k=.0118]
Hey, \color[brightorange]{orange you glad I didn't say banana?}

\definecolor[darknavy][c=.9753, m=.4444, y=0, k=.6824]
Hey, \color[darknavy]{is this dark navy?}

Defining derivative colors

Colors defined in terms of other colors are processed at the Lua end, unless they are direct clones. In that case, the new name is never told to Lua. That means that this does not work:

% direct clone, processed by TeX
\definecolor[ColorA][red]
% fails, ColorA not known to Lua
\definecolor[ColorB][.5(ColorA)]

Writing it as a fake fraction works.

% definition involves a fraction, processed by Lua.
\definecolor[ColorA][1.0(red)]
% succeeds
\definecolor[ColorB][.5(ColorA)]

Notes

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