Fix backward scrolling in buffers with header-line

* src/window.c (window_scroll_pixel_based): Account for the
header-line when comparing Y coordinate with the last_visible_y.
(Bug#29325)
This commit is contained in:
Eli Zaretskii 2017-11-23 22:29:59 +02:00
parent 8e40429c96
commit b081ec9dd7

View file

@ -5355,6 +5355,9 @@ window_scroll_pixel_based (Lisp_Object window, int n, bool whole, bool noerror)
/* We moved the window start towards BEGV, so PT may be now
in the scroll margin at the bottom. */
move_it_to (&it, PT, -1,
/* We subtract WINDOW_HEADER_LINE_HEIGHT because
it.y is relative to the bottom of the header
line, see above. */
(it.last_visible_y - WINDOW_HEADER_LINE_HEIGHT (w)
- partial_line_height (&it) - this_scroll_margin - 1),
-1,
@ -5392,11 +5395,14 @@ window_scroll_pixel_based (Lisp_Object window, int n, bool whole, bool noerror)
/* See if point is on a partially visible line at the end. */
if (it.what == IT_EOB)
partial_p = it.current_y + it.ascent + it.descent > it.last_visible_y;
partial_p =
it.current_y + it.ascent + it.descent
> it.last_visible_y - WINDOW_HEADER_LINE_HEIGHT (w);
else
{
move_it_by_lines (&it, 1);
partial_p = it.current_y > it.last_visible_y;
partial_p =
it.current_y > it.last_visible_y - WINDOW_HEADER_LINE_HEIGHT (w);
}
if (charpos == PT && !partial_p
@ -5415,7 +5421,7 @@ window_scroll_pixel_based (Lisp_Object window, int n, bool whole, bool noerror)
goal_y = this_scroll_margin;
SET_TEXT_POS_FROM_MARKER (start, w->start);
start_display (&it, w, start);
/* It would be wrong to subtract CURRENT_HEADER_LINE_HEIGHT
/* It would be wrong to subtract WINDOW_HEADER_LINE_HEIGHT
here because we called start_display again and did not
alter it.current_y this time. */
move_it_to (&it, -1, window_scroll_pixel_based_preserve_x,