patch 9.0.0908: with 'smoothscroll' cursor may end up in wrong position
Problem: With 'smoothscroll' cursor may end up in wrong position.
Solution: Correct the computation of screen lines. (Yee Cheng Chin,
closes #11502)
diff --git a/src/move.c b/src/move.c
index 66e8c18..4205445 100644
--- a/src/move.c
+++ b/src/move.c
@@ -2460,18 +2460,50 @@
used = curwin->w_cline_height;
#endif
- // If the cursor is below botline, we will at least scroll by the height
- // of the cursor line. Correct for empty lines, which are really part of
- // botline.
+ // If the cursor is on or below botline, we will at least scroll by the
+ // height of the cursor line, which is "used". Correct for empty lines,
+ // which are really part of botline.
if (cln >= curwin->w_botline)
{
scrolled = used;
if (cln == curwin->w_botline)
scrolled -= curwin->w_empty_rows;
min_scrolled = scrolled;
- if (cln > curwin->w_botline && curwin->w_p_sms && curwin->w_p_wrap)
- for (linenr_T lnum = curwin->w_botline + 1; lnum <= cln; ++lnum)
- min_scrolled += PLINES_NOFILL(lnum);
+ if (curwin->w_p_sms && curwin->w_p_wrap)
+ {
+ // 'smoothscroll' and 'wrap' are set
+ if (cln > curwin->w_botline)
+ // add screen lines below w_botline
+ for (linenr_T lnum = curwin->w_botline + 1; lnum <= cln; ++lnum)
+ min_scrolled += PLINES_NOFILL(lnum);
+
+ // Calculate how many screen lines the current top line of window
+ // occupies. If it is occupying more than the entire window, we
+ // need to scroll the additional clipped lines to scroll past the
+ // top line before we can move on to the other lines.
+ int top_plines =
+#ifdef FEAT_DIFF
+ plines_win_nofill
+#else
+ plines_win
+#endif
+ (curwin, curwin->w_topline, FALSE);
+ int skip_lines = 0;
+ int width1 = curwin->w_width - curwin_col_off();
+ int width2 = width1 + curwin_col_off2();
+ // similar formula is used in curs_columns()
+ if (curwin->w_skipcol > width1)
+ skip_lines += (curwin->w_skipcol - width1) / width2 + 1;
+ else if (curwin->w_skipcol > 0)
+ skip_lines = 1;
+
+ top_plines -= skip_lines;
+ if (top_plines > curwin->w_height)
+ {
+ scrolled += (top_plines - curwin->w_height);
+ min_scrolled += (top_plines - curwin->w_height);
+ }
+ }
}
/*