kat.nvim

A NeoVim theme with warm blue tones. This is a Fennel remake of my kat.vim colorscheme, using Aniseed. Lua is provided, along with an embedded Aniseed environment.

Built with Lua, this them is dynamic with only a few predefined colors. Almost everything is generated dynamically. Syntax is built off of groups, all statements inherent the colors of its parent color.

Installation:

Install with your plugin manager of choice. Example for vim-plug:

" kat.nvim
Plug 'katawful/kat.nvim'

Example:

Usage

There are only 2 colorscheme files provided: kat.nvim and kat.nwim. The former is a harder contrast, the latter is a softer contrast (the name being shortened from kat.nvim-owo). To set between dark and light schemes, the :set background method is used. Simply set the contrast to whichever you prefer, and set your background in your NeoVim configs.

See the examples above for the differences.

Rendered Support

By default this color scheme will use pre-compiled files to set colors. This is a massive performance benefit, shaving almost 25ms off of my startup time for this plugin on my system (~30ms to ~6ms). The old method of setting colors can be used if wanted. Simply set vim.g.kat_nvim_dont_render to true and reload the colorscheme.

The rendered files themselves support any lingering 0.6 features, and work with each variant and with terminal colors.

0.7 support

This plugin uses Neovim 0.7 features if available. There is no major difference in use with older versions for this plugin, but as time continues and 0.7 feature become the norm, 0.6 support and below will slowly be taken out of this plugin. A deprecation process will be done when this starts.

For those wondering, when comparing 0.7 and 0.6 based highlighting function support for rendered files, I noticed a less than 1ms difference in startup time.

Terminal Colors Support

The following terminals can have a 16 color config file generated based on the current in use kat.nvim theme:

Generate the color file like so:

:KatGenTermTheme kitty

This will generate "kitty-kat.nvim-dark.conf" at the current working directory when kat.nvim with a dark background is used.

Options

Integrations

Filetypes

Stupid Features

Due to the magic speed of Lua, in addition to the wonderful NeoVim API, I was given the ability to add in features unheard of for VimL based colorschemes. Currently the only feature is color fading for the Function highlight group. See the following image for an example. More features will be added in the future as I think of them.

Contributing

I am always open to expanding this colorscheme. This plugin was written in Fennel with Aniseed. This means there are some peculiar requirements for making a PR, in addition for my design scope.

Internal Variables

Due to how Aniseed works, and for ease of development, I require you to stick with using Aniseed's function/variable definition keywords. They get exported much more reliably from the module you write them in (assuming you don't make them private). If you are adding a new color variable for a module, first check katdotnvim.colors, katdotnvim.highlights.main, and katdotnvim.highlights.syntax for ones similar to it. If there isn't one, you have 2 options. If its local to an addition (say you need to blend a color for a statusline), it is ok to keep it within that module. If it's meant, at all, to do more, put it in katdotnvim.highlights.main or katdotnvim.highlights.syntax depending on if its a system color or a filetype color. Otherwise its best to not introduce new color variables

Color functions vs. Color variables

Additionally, in order to keep runtime functionality of :colorscheme, you cannot use def to define color variables. You must use defn to define a function that returns a string. For color variables that just need get the value from another color function, you don't need to define a variable at all:

(defn newColorVariable [] (. (colorFunctionWithLookup) :lookup))

For colors that use one of the katdotnvim.utils.color functions, you must define a variable to return. Otherwise the function will be passed to internal functions, breaking the colorscheme:

(defn newColorVariable []
  (def output (katdotnvim.utils.color.function ...))
	output)
(defn newColorVariable []
  (def output (plainColorFunction))
	output)

Compiling

You need a local build of fennel in the root directory of this repo. This is to compile the fennel files in colors/. These files are what Vim will use to let us change the colorscheme between it's various types. Thus running make will fail if you try to compile this repo without the local fennel script.

Render Color Files

Set vim.g.kat_nvim_compile_enable = true, then when inside this repo use the user command "KatNvimRenderFiles". You should then format with fnlfmt.

fnlfmt

make format will format all files with fnlfmt. It assumes that is in your $PATH.

File Structure

Pretty self explanatory, plugin integrations go in katdotnvim/highlights/integrations, filetype additions in the other folder.

Adding Options

Make sure you add the necessary option to the default function in katdotnvim/utils/error.fnl.

License

The following are directories from different, but compatible, licenses

• lua/externals/hsluv.lua
• Aniseed - distributed in lua/katdotnvim/aniseed/

hsluv is provided as free to use, being able to be integrated into this project provided it's copyright statement is kept in place. For convenience it is placed below as well:

Lua implementation of HSLuv and HPLuv color spaces
Homepage: http://www.hsluv.org/
Copyright (C) 2019 Alexei Boronine
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
associated documentation files (the "Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the
following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial
portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Aniseed is provided into the public domain, and free to use for integration under the unlicense license. See the full project for full licensing details.

Macros shipped in lua/katdotnvim/katcros-fnl is provided under the GPL v3 license. See.

The rest of the code is published under the GPL v3 license, see LICENSE.txt for details