~ / motions / screenlesson 6/6

The screen: H M L, scrolling and zz

Jump to what you can see, scroll by half or whole screens, and recenter.

?how it works

H, M and L move the cursor to the High (top), Middle and Low (bottom) line of the window. A count measures from that edge: 3H is the third line from the top, 2L the second from the bottom. They're jumps, and great for reaching anything you can see in a long file.

To travel further, scroll: CTRL-D and CTRL-U move half a screen down and up, CTRL-F and CTRL-B a whole screen forward and back. The cursor comes along. CTRL-E and CTRL-Y scroll the view one line without moving the cursor (unless it would fall off the screen).

zz, zt and zb don't move the cursor at all. They scroll so the cursor's line sits in the middle, at the top or at the bottom of the window. zz after a big jump shows you the code around where you landed.

The drill files here fit on one screen, so H and L land on the first and last lines. Scrolling depends on your window size, so it isn't drilled, but try it on a long file in Neovim.

⌨keys

`H`	top line of the window ({count}H: count from the top)
`M`	middle line of the window
`L`	bottom line of the window ({count}L: count from the bottom)
`<C-d>`	scroll half a screen down
`<C-u>`	scroll half a screen up
`<C-f>`	scroll a screen forward (down)
`<C-b>`	scroll a screen back (up)
`<C-e>`	scroll the view down one line
`<C-y>`	scroll the view up one line
`zz`	scroll so the cursor line is in the middle
`zt`	scroll so the cursor line is at the top
`zb`	scroll so the cursor line is at the bottom
`z.`	like zz, and also moves to the first non-blank

Nin neovim

Because Neovim leaves 'startofline' off, H, M, L and the CTRL-D/CTRL-U/CTRL-F/CTRL-B scrolls keep your column instead of jumping to the first non-blank. Neovim also turns the mouse on by default, and the scroll wheel scrolls the window rather than moving the cursor.

2 drills

High, middle, low: Jump to the top, middle or bottom line of the window with H, M or L. Your column stays put.
Count from the edge: Reach the target with a counted H (lines from the top) or L (lines from the bottom).

The drill editor loads in your browser.