To switch from vertical split to horizontal split fast in Vim

Vim mailing list says (re-formatted for better readability):

To change two vertically split windows to horizonally split Ctrl-w t Ctrl-w K Horizontally to vertically: Ctrl-w t Ctrl-w H Explanations: Ctrl-w t makes the first (topleft) window current Ctrl-w K moves the current window to full-width at the very top Ctrl-w H moves the current window to full-height at far left

Note that the t is lowercase, and the K and H are uppercase.

Also, with only two windows, it seems like you can drop the Ctrl-w t part because if you're already in one of only two windows, what's the point of making it current?

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Ctrl-w followed by H, J, K or L (capital) will move the current window to the far left, bottom, top or right respectively like normal cursor navigation.

The lower case equivalents move focus instead of moving the window.

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When you have two or more windows open horizontally or vertically and want to switch them all to the other orientation, you can use the following:

(switch to horizontal)

:windo wincmd K

(switch to vertical)

:windo wincmd H

It's effectively going to each window individually and using ^WK or ^WH.

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The following ex commands will (re-)split any number of windows:

To split vertically (e.g. make vertical dividers between windows), type :vertical ball

To split horizontally, type :ball

If there are hidden buffers, issuing these commands will also make the hidden buffers visible.

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In VIM, take a look at the following to see different alternatives for what you might have done:

:help opening-window

For instance:

Ctrl-W s Ctrl-W o Ctrl-W v Ctrl-W o Ctrl-W s ...

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Horizontal to vertical split Ctrl+W for window command, followed by Shift+H or Shift+L

Vertical to horizontal split Ctrl+W for window command, followed by Shift+K or Shift+J

Both solutions apply when only two windows exist.

After issuing the window command Ctrl+W, one is basically moving the window in the direction indicated by Shift+direction letter.

Opening help in a vertical split by default

Add both of these lines to .vimrc:

cabbrev help vert help
cabbrev h vert h

cabbrev stands for command abbreviation.

:vert[ical] {cmd} always executes the cmd in a vertically split window.

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Inspired by Steve answer, I wrote simple function that toggles between vertical and horizontal splits for all windows in current tab. You can bind it to mapping like in the last line below.

function! ToggleWindowHorizontalVerticalSplit()
  if !exists('t:splitType')
    let t:splitType = 'vertical'
  endif

  if t:splitType == 'vertical' " is vertical switch to horizontal
    windo wincmd K
    let t:splitType = 'horizontal'

  else " is horizontal switch to vertical
    windo wincmd H
    let t:splitType = 'vertical'
  endif
endfunction

nnoremap <silent> <leader>wt :call ToggleWindowHorizontalVerticalSplit()<cr>

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Following Mark Rushakoff's tip above, here is my mapping:

" vertical to horizontal ( | -> -- )
noremap <c-w>-  <c-w>t<c-w>K
" horizontal to vertical ( -- -> | )
noremap <c-w>\|  <c-w>t<c-w>H
noremap <c-w>\  <c-w>t<c-w>H
noremap <c-w>/  <c-w>t<c-w>H

Edit: use Ctrl-w r to swap two windows if they are not in the good order.

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