How to set the y-coordinate (in pixels) of the current line

Question

I want to scroll the buffer so that the the current line is, say, 300 pixels from the beginning of the window.

Something like this:

. \ 
. | (300 pixels)
. /
| <-- (current line)

Any ideas?

Note that the buffer may contain figures and different font sizes, so scrolling a fixed number of text lines won't do the trick.

Answer 1

You can set the vertical scroll parameter of your current window (and other windows, too) with pixel precision:

(set-window-vscroll nil 300 t)

This will however not work with any value greater than the frame height though. I've had to hand in a bug where Emacs hangs up for certain display engine configurations upon doing this even.