Lua Color

Convert and manipulate color values.

Features

• Parse a variety of color formats.
• Style Terminal output.
• Methods for common color manipulations.
• Generate color schemes from a base color.
• Supported color formats: rgb, hsv, hsl, hwb, ncol, cmyk
• Includes X11 colors.

Install

Use luarocks install lua-color or add folder to your project root.
Supports lua >= 5.1.

Documentation

The documentation is availabale here or from the docs folder.

Usage

Import

local Color = require "lua-color"

-- Use x11 color names
Color.colorNames = require "lua-color.colors.X11"

-- Use color names from file
local colors = require "lua-color.colors"
Color.colorNames = colors.load "my-colors.conf"

Create new color

-- With X11 colors enabled
local color = Color "crimson"

-- These create (roughly) the same color
-- (full list of options in the docs @see Color:set)
local color = Color "#41ba69"
local color = Color "hsva 140 65% 73% 1"
local color = Color "cmyk 65% 0% 44% 27%"
local color = Color { r = 0.255, g = 0.729, b = 0.412 }
local color = Color { 0.255, 0.729, 0.412 }
local color = Color { h = 0.389, s = 0.65, v = 0.73 }

local new_color = Color(color)

Retrieve the color

local color = Color "#ff0000"

-- Print color
print(color) -- prints: #ff0000

-- Print color as hsv
local h, s, v = color:hsv()
print(h * 360, s * 100, v * 100) -- prints: 0 100 100
print(color:tostring "hsv")      -- prints: hsv(0, 100%, 100%)

-- Print color as hwb
local h, w, b = color:hsv()
print(h * 360, w * 100, b * 100) -- prints: 0 0 0
print(color:tostring "hwb")      -- prints: hwb(0, 0%, 0%)

-- Print color as hsla
local h, s, l, a = color:hsla()
print(h * 360, s * 100, l * 100, a) -- prints: 0 100 50 1
print(color:tostring "hsla")        -- prints: hsla(0, 100%, 50%, 1)

-- Print color as rgba
local r, g, b, a = color:rgba()
print(r * 255, g * 255, b * 255, a) -- prints: 255 0 0 1
print(color:tostring "rgba")        -- prints: rgba(255, 0, 0, 1)

-- Print color as cmyk
print(color:cmyk())          --prints: 0 1 1 0
print(color:tostring "cmyk") -- prints: cmyk(0%, 100%, 100%, 0%)

-- Print color as NCol
print(color:tostring "ncol") -- prints: R0, 0%, 0%

Manipulate the color

-- Get complementary color
color:rotate(0.5)
color:rotate {deg = 180}
color:rotate {rad = math.pi}

-- Get inverse
color:invert()
local new_color = -color

-- to greyscale
color:grey()

-- to black or white depending on lightness
color:blackOrWhite()

-- Mix two colors
color:mix(other_color, 0.3) -- mix colors with 70:30 ratio
local new_color = color + other_color -- mix colors 50:50 and return new
local new_color = color - other_color -- complement of +
-- Example: #ff0000 + #00ff00 = #808000 (you can use 'color:set {value = 1}' to get #ffff00)
--          #ff0000 + #00ff00 = #000080

-- Apply mask
local new_color = color & 0xff00ff -- Get color without green component

Generate color scheme

-- Complementary
local complementary_color = color:complement()

-- Analogous
local new_a, orig, new_b = color:analogous()

-- Triadic
local orig, new_a, new_b = color:triad()

-- Tetradic
local orig, new_a, new_b, new_c = color:tetrad()

-- Compound
local new_a, orig, new_b = color:compound()

-- Pentadic (and so forth)
local cols = color:evenlySpaced(5)

-- Combine
-- Example: Analogous color scheme around complement
local new_a, new_b, new_c = color:complement():analogous()

Other

-- Check if variable is color
if Color.isColor(color) then print "It's a color!" end

-- Compare lightness of colors
if Color "#000000" > Color "#ffffff" then
    print "Black is lighter than white!" -- Never runs
end

-- Equate colors
assert(color == color:clone())

Terminal colors

local tc = require "lua-color.terminal"

-- Print red text
io.write(tc.set { color = Color "rgb 255 0 0" })
print("Hello world")
io.write(tc.set { color = "default" })

-- Print red text (resets all styles afterward, not just color)
print(tc.apply {
    color = Color "rgb 255 0 0",
    to = "Hello world"
})

-- Make text italic and underlined
print(tc.apply {
    tc.Effect.italic | tc.Effect.underline,
    to = "Hello world"
})

-- Make text italic and underlined
print(tc.apply {
    italic = true,
    underline = true,
    to = "Hello world"
})