Re: Scrolling over images/tall lines

[Eli Zaretskii <eliz@gnu.org>]

> From: Yuan Fu <casouri@gmail.com>
> Date: Mon, 2 Nov 2020 16:48:59 -0500
> 
> P.S. The case where I have to set window-start and window-vscroll in the same time is this: consider this window:
> 
>  (1)--------------------+
>  |                      |
>  |        image         |
>  |                      |
>  |                      |
>  |                      |
>  +----------------------+
> +------window top--------------+
> |==========line==========      |
> |==========line==========      |
> |==========line==========      |
> 
> If I now scroll up one line, I want to see this:
> 
>  (1)--------------------+
>  |                      |
>  |        image         |
>  |                      |
>  |                      |
> +------window top--------------+
> ||                      |      |
> |+----------------------+      |
> |==========line==========      |
> |==========line==========      |
> |==========line==========      |
> 
> Which requires setting window-start to (1) and setting vscroll to image-height - default-line-height.

Why can't you achieve the same by leaving window-start at its original
place (2) and setting vscroll to get the display you want, like this:

 +----------------------+
 |                      |
 |        image         |
 |                      |
 |                      |
+------window top--------------+--
||                      |      | ^
|+----------------------+      | | vscroll (negative)
|(2)=======line==========      | v
|==========line==========      |
|==========line==========      |

Did you try this method?