bug#65214: 29.1; Tall images in 'image-mode' can't be scrolled with 'pixel-scroll-precision-mode' on

[Rahguzar]

Hi Po,

Po Lu <luangruo@yahoo.com> writes:

> I tried to fix this differently on master.  Please see if it resolves
> your problem (and other issues with scrolling past large images.)
>
> As always, keep an eye out for performance regressions.  Thanks.


The issue is still there and can be reproduced by evaluating

(let* ((win (display-buffer (get-buffer-create "image-pixel-precision-test")))
       (height (* (window-text-height win t) 2))
       (file "path/to/image"))
  (select-window win)
  (erase-buffer)
  (insert-image (create-image file nil nil))
  (goto-char 1)
  (pixel-scroll-precision-mode)
  nil)

The resulting image cannot be scrolled.

In the new code this is because vscroll is reset to 0 inside the binding
for `line-after`. Commenting out that line allows me to scroll the
image.

Rahguzar