Scroll Mode for Vim

“Scroll mode” is a new mode for Vim that allows to scroll a text buffer with classical h/j/k/l bindings and some others, that are all designed for one-hand usage. Forget about <C-f>, <C-d>, and G. You don't need to keep holding modifier keys anymore — everything can be done with single-key mappings!

New key mappings available in the Scroll mode:

• j / k — scroll 5 lines down / up
• l / h — scroll page down / up
• b — scroll to the ending of the buffer (bottom)
• u — scroll to the beginning of the buffer (up)
• ; — quit the Scroll mode
• - — quit the Scroll mode and delete the buffer

With these mappings, you can quickly look around, walk through several screens of text, and when you are in the right place return back to normal mode for more accurate text manipulations.

For example, compare this scenario of a scrolling session in normal mode and in Scroll mode.

	Normal Mode	Scroll Mode
1.	shift g	b
2.	ctrl b	h
3.	ctrl b	h
4.	k k k k k k k k	j j
	13 keys (including 3 modifiers)	5 keys, all for one hand

Since Scroll mode is in fact just a wrapper around normal mode, all keys, that are not remapped by Scroll mode continue to be available: searching (/, ?, n, N), window managing (<C-w>), etc.

If you enter another mode (Command mode, Insert mode, etc.) while Scroll mode is active, then it will be implicitly automatically finished, all Normal mode mappings will be restored, and you will be able to proceed in the mode of your choice.

Installation

Plugin Manager	Command
vim-plug	Plug 'GeneZharov/vim-scrollmode'
vundle	Plugin 'GeneZharov/vim-scrollmode'
pathogen.vim	git clone '[email protected]:GeneZharov/vim-scrollmode.git' ~/.vim/bundle/vim-scrollmode
native pack (:h packages)	git clone '[email protected]:GeneZharov/vim-scrollmode.git' ~/.vim/pack/dist/start/vim-scrollmode

Set a preferred shortcut to enter the Scroll mode:

nmap <Leader>; <Plug>ScrollMode

I prefer to use Scroll mode with a <Space> as my <Leader> key:

" Place it before all the <Leader> mappings
map <SPACE> <Nop>
let mapleader = "\<Space>"

Configuration

Scrolling Settings

• g:scrollmode_actions

  This option allows to configure default Scroll mode key mappings. These key mappings are internally set with the following dictionary.

  \ {
  \ "up": ["k", "<Up>"],
  \ "down": ["j", "<Down>"],
  \ "pagedown": ["l"],
  \ "pageup": ["h"],
  \ "bottom": ["b"],
  \ "top": ["u"],
  \ "exit": [";"],
  \ "bdelete": ["-"]
  \ }

  You can specify any subset of this dictionary as a value for this option in order to override default mappings.

  For example, to add <Esc> key to the keys that exit the Scroll mode:

  let g:scrollmode_actions = {
    \ "exit": [";", "<Esc>"],
    \ }

  I didn't make <Esc> to quit the Scroll mode as default behavior, because in the terminal Vim (but not Neovim) it can break some complex keys like <Up> and <Down> while the Scroll mode is active. If you are not going to use these keys in the Scroll mode or if you use a different Vim version (GVim, Neovim), then you are welcome to use the config from the example above.

• g:scrollmode_mappings

  With this option, you can specify new mappings available in the Scroll mode. This option has precedence over g:scrollmode_actions, so you can rebind a default action with any custom command.

  For example, let's add a custom command for buffer deletion:

  let g:scrollmode_mappings = {
    \ ":Bdelete<CR>": ["-", "c"]
    \ }

  When the Scroll mode is activated, this code will internally result to:

  nnoremap <silent> <buffer> - :Bdelete<CR>
  nnoremap <silent> <buffer> c :Bdelete<CR>

• g:scrollmode_distance

  Number of lines to scroll at once by j / k ("up" and "down" actions).

  Default: 5

Scrolling Indicators

• g:scrollmode_cmdline_indicator

  Enables or disables the Scroll mode indicator in the command line. The indicator looks similar to other indicators for built-in modes and looks like this:

  -- SCROLL --
  

  Default: v:true

• g:scrollmode_statusline_highlight

  Enables or disables StatusLine highlighting, when the Scroll mode is activated. Has no effect with plugins that replace the status line (Airline, Powerline, Lightline).

  I am not fully satisfied with how this feature works, so it is disabled by default. But if you need Scroll mode to be more noticeable and colorful, then you can enable this option. See the options below for color customization.

  Default: v:false

Highlight Groups

Options for status line color customization. Only have effect if g:scrollmode_statusline_highlight is enabled.

• g:scrollmode_statusline_group

  Highlight group that is used for StatusLine when the Scroll mode is active.

  Default: "DiffAdd"

• g:scrollmode_statusline_group_edge

  Highlight group that is used for StatusLine when the Scroll mode is active and the top/bottom edge of the buffer is reached. The color helps to notice that you can't scroll in that direction anymore. Specify v:null if you don't need this behavior.

  Default: "DiffChange"

Hooks

• g:ScrollmodeOnQuit

  Funcref that is called after you exit the Scroll mode.

  function! s:fn() abort
    " ... your code
  endfunction
  
  let g:ScrollmodeOnQuit = function("s:fn")

License

MIT license