Colorschemes

rtdvi reads vim .vim colorscheme files directly. No custom format.

Switching

:colorscheme desert
:colo default

:colorscheme with no argument prints the currently-loaded name.

Search paths

For :colorscheme NAME, rtdvi looks for NAME.vim in this order:

1. ./colors/NAME.vim (CWD)
2. $XDG_CONFIG_HOME/rtdvi/colors/NAME.vim
3. $HOME/.config/rtdvi/colors/NAME.vim
4. /usr/share/vim/vim*/colors/NAME.vim (whatever's installed)

The first match wins. The system path means you get vim's bundled schemes (desert, default, evening, morning, slate, …) for free if you have vim installed.

Default scheme at startup

rtdvi tries default, then desert — first one found wins. If neither exists (no system vim installed), it falls back to the built-in vim defaults (everything still gets sensible colors).

File format rtdvi understands

Only highlight directives — every other vim-script line (let, set, if, endif, syntax …, …) is silently skipped.

Simple group definition

highlight Comment   ctermfg=cyan       guifg=#80a0ff term=bold cterm=bold
highlight Search    ctermbg=3          guibg=#c0c000
highlight Statement ctermfg=yellow                  cterm=bold

Recognised keys:

NONE / bg / empty values are ignored, so old vim schemes with gui=NONE don't accidentally clobber anything.

Linking

highlight default link rustKeyword Statement
hi link cIncluded cString

hi link FROM TO aliases one group to another. Vim's default / def keywords are accepted. Chains of links are followed (depth-capped at 16 to defend against malformed files).

hi clear

hi clear

Wipes every group and link defined so far in this scheme. Useful when a scheme starts by clearing inherited definitions.

cterm vs gui — which wins?

When both ctermfg=… and guifg=… are supplied for the same group, rtdvi picks based on the $COLORTERM env var:

• COLORTERM=truecolor or COLORTERM=24bit → guifg (RGB) wins.
• Anything else → ctermfg (16-color palette) wins.

This means schemes work on basic terminals too, instead of emitting RGB escapes that get ignored. If your terminal supports 24-bit color and you want the richer scheme, export COLORTERM=truecolor.

Vim defaults are always applied

After parsing a scheme, rtdvi layers syncolor.vim's default group definitions and standard SynLink mappings on top — only filling in groups the user's scheme didn't define. This is critical because most schemes only define a handful of groups (Comment, Search, …) and rely on vim's defaults for the rest (Statement, Type, Constant, …).

Defaults wired in:

• Standard links: String→Constant, Number→Constant, Boolean→Constant, Function→Identifier, Conditional→Statement, Repeat→Statement, Label→Statement, Keyword→Statement, Operator→Statement, Exception→Statement, Include→PreProc, Define→PreProc, Macro→PreProc, PreCondit→PreProc, StorageClass→Type, Structure→Type, Typedef→Type, Tag→Special, SpecialChar→Special, Delimiter→Special, SpecialComment→Special, Debug→Special.
• Base group colors (dark-bg variant from vim's syncolor.vim): Comment, Constant, Special, Identifier, Statement, PreProc, Type, Underlined, Error, Todo, Title, Search.

So even a one-line highlight Comment … user scheme produces a fully styled editor.

Writing your own scheme

Example scheme file (~/.config/rtdvi/colors/myscheme.vim):

" Vim color file
hi clear Normal
set bg&
hi clear
if exists("syntax_on")
  syntax reset
endif
let colors_name = "myscheme"
highlight Search    ctermbg=3       guibg=#c0c000
highlight Comment   term=bold cterm=bold ctermfg=cyan  guifg=#80a0ff

You don't need the let/set/if/syntax reset boilerplate for rtdvi's parser — they're harmless but ignored. The minimal scheme is just a handful of highlight lines.