Re: Displaying scrollable images in a grid-layout

[Eli Zaretskii <eliz@gnu.org>]

> From: Andreas Politz <politza@hochschule-trier.de>
> Date: Mon, 13 Apr 2015 21:35:40 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > I cannot try your recipe [...]
> 
> Try this:

Thanks, will do later.

> > That being said, I think you are missing the PIXELWISE-P argument of
> > both window-vscroll and set-window-vscroll.  Aren't you?  
> 
> No both versions do nothing with above scroll settings for any argument
> I've tried (unless the window is smaller than the first displayed
> image).
> 
> > If not, please elaborate on what kind of partial scrolling did you
> > want to see.
> >
> 
> doc-view let's you scroll the page, i.e. the image is only partially
> visible.  I want the same behaviour for more than one image in the
> buffer. Possible display state with 2 images:

If each image is taller than the window, a simple down-arrow should do
what you want.  (Isn't that what you see in doc-view?)  If the images
are smaller than the window height, why is such scrolling useful?
Emacs tries very hard not to show partial characters and images; what
you are trying to do works against the very design of redisplay, so it
seems.  What's the rationale?

> (set-window-vscroll nil 10) => Nothing happens.
> (set-window-vscroll nil 99) => Nothing happens.
> (set-window-vscroll nil 100 t) => Nothing.

What is the height of the image?  If it's smaller than these offsets,
Emacs won't let you do that, because you are trying to move point out
of the visible portion of the window.

P.S.  Please don't remove the list from the addressees, I don't think
we should make this a private off-list discussion.  Thanks.