colorpal.vim

With colorpal, you can define an RGB palette to use in the creation of Vim color schemes. The equivalent terminal colors are automatically set. It also comes with commands that lets you temporarily adjust the color scheme.

Rationale

Neovim and various terminal emulators have supported 24 bit color for a while now. Being able to highlight text in more than 240 colors has its advantages and just looks nicer. But, it's tedious to make adjustments to both cterm and gui colors.

I work in the terminal and have a bad habit of only setting cterm colors in my color scheme. As a result, colors look bad when I need to use a GUI version of Vim. I imagine the problem is the same for those who primarily use GUI Vim.

Installation

Any plugin manager will work.

Commands

Command	Description
CPSaturate	Saturate all colors
CPDesaturate	Desaturate all colors
CPLighter	Ligthen all colors
CPDarker	Darken all colors
CPBrighter	Brighten all colors
CPDimmer	Dim all colors
CPNegative	Negative colors (inverted hue)
CPInvert	Invert colors (inverted hue, saturation, and lightness)
CPReset	Reset color scheme to original colors
CPHL	Command to use the user-defined palette in color schemes

Usage

Note: If you only want the color adjustment commands, you don't need to create a palette and color scheme using this pluign.

Start by creating a palette:

let g:colorpal_palette = {
      \ 'red': 'ff0000',
      \ 'green': '00ff00',
      \ ...etc...
      \ 'blue': '0000ff',
      \ 'emo': '000000',
      \ }

The color names can be anything, but they can't have spaces or commas. Then create your own color scheme. For example:

" Example File: colors/mytheme.vim

call colorpal#begin()
highlight clear
if exists('syntax_on')
  syntax reset
endif

set background=dark
let g:colors_name = 'mytheme'

CPHL Normal green emo
...etc...
CPHL ErrorMsg red - bold
CPHL WarningMsg red,s-=0.4 - bold

Then you would set colorscheme to mytheme

The CPHL command takes up to 4 arguments separated by spaces: group (required), fg, bg, and style. A dash (-) denotes that the field will not be set.

The fg and bg fields require the names that are defined in your palette. They take optional adjustments, such as s-=0.4 above which decreases the saturation by 40% of the current saturation value. The adjustments operate on HSL values. h+=40 rotates the Hue by 30 degrees, s+=40 increases saturation by 40%, and l+=40 increases lightness by 40%.

For saturation and lightness, integer values are divided by 100. Float values are taken as-is. s-=0.4 and s-=40 mean the same thing.

For hue, the value is taken as-is. h-=0.4 rotates the hue by -0.4 degrees and h-=40 rotates the hue by -40 degrees.

The operators += and -= adjusts the current value. The operators + and - (without =) adds or subtracts the amount to the current value.

Given that s=0.5:

• s-=0.4 is expressed as 0.5 - (0.5 * 0.4), which equals 0.2
• s-0.4 is expressed as 0.5 - 0.4, which equals 0.1

There are named adjustments: li[ght], da[rk], br[ight], di[m], ne[gative], co[mplement]. The adjustments light, dark, bright, and dim will adjust values by 0.1. negative gives the opposite RGB color, and complement gives the opposite RYB color.

Adjustments can be chained. For example, to get a bright green color:

CPHL WarningMsg red,complement,s+=10 - bold
" Could be shortened to:
CPHL WarningMsg red,co,s+=10 - bold

base16

Todo: write this