nortia.nvim - temporal colour scheme for neovim

This is neovim only, this will not work with legacy vim

Preview

What is it

Nortia is designed as a configurable and dynamic colour scheme, which by default changes colour during the day. In daylight hours it's a light colourscheme with configurable contrast, and at night it's a dark colourscheme. I built this because I found myself preferring a light colourscheme when my office was bright, but it was too jarring when in lower light conditions. Since using this for a while, as it changes on the hour, it's also useful for keeping track of the time. The colourscheme is made with lush.nvim as the base, and uses the Oklab perceptual colour space in order to determine some complementary colours for syntax highlighting. The colours picked are designed to be spread across the various hues, such that they are complementary to each other and of equal luminence.

Installing

This requires lush.nvim to be installed also, so with a plugin manager such as vim-plug it should just be:

Plug 'rktjmp/lush.nvim'
Plug 'alaric/nortia.nvim'


color nortia-nvim

Light and Dark

The colour scheme uses the same basic palette of colours for the syntax elements when using both light and dark backgrounds, however they can be adjusted differently according to the background. For instance the background accent colours are changed to be darker than the light background, and lighter than the dark background.

Although the scheme automatically changes on the hour throughout the day, this can of course be overriden to suit your conditions.

To set to 1am (dark):

:lua require('nortia.theme').set_hour(1)

To set to 10am (light):

:lua require('nortia.theme').set_hour(10)

To set to 4pm (inbetween):

:lua require('nortia.theme').set_hour(16)

To reset to automatically changing on the hour:

:lua require('nortia.theme').set_hour(-1)

Automatic contrast

The colorscheme automatically adjusts the primary palette to ensure a minimum contrast ratio is achieved. This is usually most difficult on the lighter backgrounds, where colours have to be darkened to produce the intended ratio. I've defaulted it to 2.5 which seems to work well for me, but is far from the W3C standard of 4.5.

If the default threshold is not sufficient for you, the contrast threshold can be configured like:

:lua require('nortia.theme').set_contrast_threshold(3.5)

Tinting

This allows the foreground or background or both to be tinted with a colour for those who prefer a slightly coloured rather than greyscale bg/fg.

:lua require('nortia.theme').tint_bg(190, 0.1)
:lua require('nortia.theme').tint_fg(190, 0.1)
:lua require('nortia.theme').tint(190, 0.1)

The first parameter is the 0-360 hue in degress, the second is the chroma from Oklab. The lightness is derived from the hour of the day.

:lua require('nortia.theme').tint_bg(0, 0.05)

:lua require('nortia.theme').tint_bg(190, 0.1)

Changing the Base

:lua require('nortia.theme').set_base(r, g, b)

This sets the base colour with the r, g, b parameters (0-255), the default value is 255, 189, 60 if you want to return to normal.

The above preview was generated with:

:lua require('nortia.theme').set_base(235, 84, 84)

Integration with bat

The theme supports bat being used inside the neovim instance, such as fzf previews. These variables can be set to change the bat theme as the Nortia theme changes from light to dark through the day.

• g:nortia_bat_light_theme: Set as light background bat theme
• g:nortia_bat_dark_theme: Set as dark background bat theme

Status

The base of the colour scheme is complete in terms of functionality, but it still needs some tweaking for TreeSitter and different language syntaxes/plugins. This might lead to some colours in the palette still changing.