WetDesertRock / vivid

Vivid is a simple lua library for dealing with simple color math.

vivid.lua

One file simple color manipulation library. Used for color conversion and math.

All functions can take an alpha after the three components of a color. This variable is not modified, but passed through for convenience. Whenever you pass a color, you can either pass a table or an unpacked list of arguments.

Included in this repository is a simple example using Quickie that demonstrates the uses of this library. It can also serve as a tool if you need a good color picking utility for when you use this library. If it has problems finding vivid you will either need to make a symlink or just copy the file over.

All conversion formulas are taken from EasyRGB with the exception of HuSL (which is not included yet).

Available Colorspaces

This library works in the following colorspaces:

• RGB (0-1)
• HSL (0-1)
• HSV (0-1)
• XYZ
• CIE L*ab (Known as Lab in the code)
• CIE-L*CH (Known as LCH in the code)
• CIE-L*uv (Known as Luv in the code)

And hopefully soon:

• HuSL (not supported, I do not want to decipher coffeescript just yet)

Conversion from RGB

vivid.RGBtocolorspace(r,g,b,a)

Returns the four components of colorspace.

print(vivid.RGBtoHSL(10,20,10,100))

Conversion to RGB

vivid.colorspacetoRGB(h,s,l,alpha)

Return r,g,b,a components of the colorspace input.

print(vivid.HSVtoRGB(0,1,0.5))

Additional Conversion Functions

vivid.XYZtoLab(x,y,z,alpha)

vivid.LabtoXYZ(l,a,b,alpha)

vivid.XYZtoLuv(x,y,z,alpha)

vivid.LuvtoXYZ(l,u,v,alpha)

vivid.LabtoLCH(l,a,b,alpha)

vivid.LCHtoLab(l,c,h,alpha)

Color Manipulations

Most of these manipulations take color which looks like {r,g,b,a} or just four more arguments r,g,b,a, performs the operation, and returns the modified color. Color spaces used are chosen due to my somewhat limited understanding on how each performs.

vivid.lighten(amount, color)

Uses the HSL colorspace.

vivid.darken(amount, color)

Uses the HSL colorspace.

vivid.saturate(amount, color)

Uses the HSV colorspace.

vivid.desaturate(amount, color)

Uses the HSV colorspace.

vivid.hue(hue, color)

Sets the hue using HSL.

vivid.invert(color)

Inverts the color using simple RGB inversion.

vivid.invertHue(color)

Inverts the color using simple 1-hue inversion in HSL.

Utility Functions

vivid.HSVSpread(count,hoffset,s,l,a)

vivid.HSLSpread(count,hoffset,s,v,a)

vivid.LCHSpread(count,l,c,hoffset,a)

These functions return an even spread of colors across a color space. It will take evenly spaced h values across the whole colorspace and use the other given values for colors. Useful for quick and easy color scheme generation for random colors and such. count is how many colors you want, and hoffset is the hue offset.

vivid.wrapcolorspace(fn)

Wraps fn that may normally take RGBA arguments to take colorspace argument.