patch 8.1.0372: screen updating slow when 'cursorline' is set
Problem: Screen updating slow when 'cursorline' is set.
Solution: Only redraw the old and new cursor line, not all lines.
diff --git a/src/move.c b/src/move.c
index b2b8486..68f8ae4 100644
--- a/src/move.c
+++ b/src/move.c
@@ -123,6 +123,10 @@
set_empty_rows(wp, done);
}
+#ifdef FEAT_SYN_HL
+static linenr_T last_cursorline = 0;
+#endif
+
/*
* Redraw when w_cline_row changes and 'relativenumber' or 'cursorline' is
* set.
@@ -140,7 +144,22 @@
&& !pum_visible()
# endif
)
- redraw_win_later(wp, SOME_VALID);
+ {
+#ifdef FEAT_SYN_HL
+ if (!wp->w_p_rnu && wp->w_redr_type <= VALID && last_cursorline != 0)
+ {
+ // "last_cursorline" may be set for another window, worst case we
+ // redraw too much. This is optimized for moving the cursor around
+ // in the same window.
+ redrawWinline(wp, last_cursorline, FALSE);
+ redrawWinline(wp, wp->w_cursor.lnum, FALSE);
+ last_cursorline = wp->w_cursor.lnum;
+ redraw_win_later(wp, VALID);
+ }
+ else
+#endif
+ redraw_win_later(wp, SOME_VALID);
+ }
}
/*