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vimscrolltext-cursor
john-jones
john-jones

Reputation: 7780

Vim scrolling without changing cursors on-screen position

When cursor is at middle of screen and i scroll down, the cursor moves upwards on the screen. I don't want it to do that.

How can i scroll without changing cursors on-screen position?

Solution, added after answer:

noremap <C-k> 14j14<C-e>
noremap <C-l> 14k14<C-y>

Upvotes: 39

Views: 15748

Answers (6)

M Kelly
M Kelly

Reputation: 81

There are two methods I know of. Add these lines to your .vimrc file (selecting only one of the two methods):

Method 1:

function! s:GetNumScroll(num)
  let num_rows = winheight(0)
  let num_scroll = a:num
  if (a:num == -1)
    let num_scroll = (num_rows + 1) / 2
  elseif (a:num == -2)
    let num_scroll = num_rows
  endif
  if (num_scroll < 1)
    let num_scroll = 1
  endif
  return num_scroll
endfunction

function! s:RtrnToOrig(before_scr_line)
  normal H
  let delta = a:before_scr_line - winline()
  while (delta != 0)
    if (delta < 0)
      let delta = winline() - a:before_scr_line
      let iter = 1
      while (iter <= delta)
        execute "normal" "gk"
        let iter +=1
      endwhile
    elseif (delta > 0)
      let iter = 1
      while (iter <= delta)
        execute "normal" "gj"
        let iter +=1
      endwhile
    endif
    let delta = a:before_scr_line - winline()
  endwhile
endfunction

function! s:scrollUP(num)
  let num_scroll = <SID>GetNumScroll(a:num)
  let num_rows = winheight(0)
  " -------------
  let before_scr_line = winline()
  normal L
  let after_scr_line = winline()
  let extra = num_rows - after_scr_line
  let extra += num_scroll
  " move by 1 to prevent over scrolling
  let iter = 1
  while (iter <= extra)
    execute "normal" "gj"
    let iter +=1
  endwhile
  " -------------
  call <SID>RtrnToOrig(before_scr_line)
endfunction

function! s:scrollDN(num)
  let num_scroll = <SID>GetNumScroll(a:num)
  " -------------
  let before_scr_line = winline()
  normal H
  let after_scr_line = line(".")
  execute "normal" "gk"
  let after_scr2_line = line(".")
  if ( (after_scr_line == after_scr2_line) && (after_scr_line > 1) )
    execute "normal" "gk"
  endif
  let extra = (num_scroll - 1)
  let extra += (winline() - 1)
  " move by 1 to prevent over scrolling
  let iter = 1
  while (iter <= extra)
    execute "normal" "gk"
    let iter +=1
  endwhile
  " -------------
  call <SID>RtrnToOrig(before_scr_line)
endfunction

 nmap <silent> <C-J>     :call <SID>scrollUP(1)<CR>
 nmap <silent> <C-K>     :call <SID>scrollDN(1)<CR>
 nmap <silent> <C-F>     :call <SID>scrollUP(-1)<CR>
 nmap <silent> <C-B>     :call <SID>scrollDN(-1)<CR>
 nmap <silent> <PageDown>:call <SID>scrollUP(-2)<CR>
 nmap <silent> <PageUp>  :call <SID>scrollDN(-2)<CR>

This uses the normal H, L to go to screen top, bot and the gk, gj commands to move up, down by screen line instead of actual line. Its more complicated than would seem needed just to work correctly when lines are longer than the screen width and wordwrap is on.

Or this method (which has previously been posted in vim tips wiki and on Stack Exchange):

Method 2:

" N<C-D> and N<C-U> idiotically change the scroll setting
function! s:Saving_scrollV(cmd)
  let save_scroll = &scroll
  execute "normal" a:cmd
  let &scroll = save_scroll
endfunction

" move and scroll
 nmap <silent> <C-J>           :call <SID>Saving_scrollV("1<C-V><C-D>")<CR>
 vmap <silent> <C-J> <Esc>     :call <SID>Saving_scrollV("gv1<C-V><C-D>")<CR>
 nmap <silent> <C-K>           :call <SID>Saving_scrollV("1<C-V><C-U>")<CR>
 vmap <silent> <C-K> <Esc>     :call <SID>Saving_scrollV("gv1<C-V><C-U>")<CR>

 nmap <silent> <C-F>           :call <SID>Saving_scrollV("<C-V><C-D>")<CR>
 vmap <silent> <C-F> <Esc>     :call <SID>Saving_scrollV("gv<C-V><C-D>")<CR>
 nmap <silent> <PageDown>      :call <SID>Saving_scrollV("<C-V><C-D>")<CR>
 vmap <silent> <PageDown> <Esc>:call <SID>Saving_scrollV("gv<C-V><C-D>")<CR>

 nmap <silent> <C-B>           :call <SID>Saving_scrollV("<C-V><C-U>")<CR>
 vmap <silent> <C-B> <Esc>     :call <SID>Saving_scrollV("gv<C-V><C-U>")<CR>
 nmap <silent> <PageUp>        :call <SID>Saving_scrollV("<C-V><C-U>")<CR>
 vmap <silent> <PageUp> <Esc>  :call <SID>Saving_scrollV("gv<C-V><C-U>")<CR>

The only issue I have with the second method is when lines are longer than the screen width and wordwrap is on then the cursor can move up or down some to account for the extra lines from the wrap. Also at the very top and bottom of the file the cursor can move. The first method really attempts to never move the cursor in all cases.

Upvotes: 1

Alexey
Alexey

Reputation: 4061

This changes the cursor on-screen position, but does not change the cursor line on-screen position:

noremap <C-k> @="1\<lt>C-D>"<CR>:set scroll=0<CR>
noremap <C-l> @="1\<lt>C-U>"<CR>:set scroll=0<CR>

This however resets the scroll option, so subsequent <C-D> and <C-U> will scroll by half screen. Without set scroll=0, the scroll option would have been set to 1, and subsequent <C-D> and <C-U> would be scrolling by one line (Vim is weird).

Probably a Vimscript function based on 1<C-D> and 1<C-U> would be the best.

Upvotes: 0

Matthias 009
Matthias 009

Reputation: 1702

ctrl-D and ctrl-U is what you want.

ctrl-D has the same effect as 14j14<C-e> (just that the number 14 is not hard coded and the amount of movement depends on the actual size of your screen): You move the cursor several lines down in the text but the cursor stays in the middle of the screen.

Similarly ctrl-U works like 14k14<C-y>.

Addendum: If your screen has 30 lines then the the two are exactly the same.

Upvotes: 13

Alok Singhal
Alok Singhal

Reputation: 96101

There are two ways I can think of: ctrl-E and ctrl-Y scroll the buffer without moving the cursor's position relative to the window. I think that is what you want. Also, if you set scrolloff to a large number, you will get the same effect as ctrl-E and ctrl-Y with the movement keys. scrolloff setting will make it hard to get the cursor to move vertically relative to the window though. (Use something like :set so=999, so is an abbreviation for scrolloff.)

:help 'scrolloff'
:help scrolling

Upvotes: 49

IvanM
IvanM

Reputation: 3053

Try this mapping in .vimrc 

map <ScrollWheelUp>   5<C-Y>
map <ScrollWheelDown> 5<C-E>

Upvotes: 1

wds
wds

Reputation: 32283

If you want to both move the cursor and the viewport with the cursor anywhere in the screen, perhaps you should set up some custom key bindings to do both at once.

Such as:

:nnoremap <C-M-u> j<C-e>

This will move the cursor down (j) and move the viewport (Ctrl-e) whenever you press Ctrl-Alt-u (only in normal mode).

Upvotes: 11

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