Subject: bug#16840: 24.3.50; Jerky motion and up/down asymmetry scrolling images in Eww

From: Lars Ingebrigtsen <[email-masked]>
Date: Fri, 27 Sep 2019 16:12:31 +0200

Eli Zaretskii <[email-masked]> writes:

> Your code generates an image whose height is smaller than the window
> height, and in that case Emacs scrolls the entire image off the window
> in one go, because all of the image was already visible once.

Oh, the

  (set-frame-height (window-frame (selected-window)) 1000 nil t)

bit didn't work?  That was supposed to ensure that the window was
shorter than the image...

> If I decrease the frame height so that the image becomes taller than
> the window, the image is scrolled partially until you had a chance to
> see all of it, then the rest is scrolled away in one large step.  This
> is exactly how the code in simple.el is designed and implemented, so I
> see no bug here.

It might be how it's designed, but it's (as you can see from this bug
report) behaviour that people find surprising.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no