Merge branch 'vim-with-runtime' into feat/rel-line-numbers
[vim_extended.git] / src / move.c
blob423284b5ea3e0fca23e303ee688a46a09c91eb87
1 /* vi:set ts=8 sts=4 sw=4:
3 * VIM - Vi IMproved by Bram Moolenaar
5 * Do ":help uganda" in Vim to read copying and usage conditions.
6 * Do ":help credits" in Vim to see a list of people who contributed.
7 * See README.txt for an overview of the Vim source code.
8 */
9 /*
10 * move.c: Functions for moving the cursor and scrolling text.
12 * There are two ways to move the cursor:
13 * 1. Move the cursor directly, the text is scrolled to keep the cursor in the
14 * window.
15 * 2. Scroll the text, the cursor is moved into the text visible in the
16 * window.
17 * The 'scrolloff' option makes this a bit complicated.
20 #include "vim.h"
22 static void comp_botline __ARGS((win_T *wp));
23 static int scrolljump_value __ARGS((void));
24 static int check_top_offset __ARGS((void));
25 static void curs_rows __ARGS((win_T *wp, int do_botline));
26 static void validate_botline_win __ARGS((win_T *wp));
27 static void validate_cheight __ARGS((void));
29 typedef struct
31 linenr_T lnum; /* line number */
32 #ifdef FEAT_DIFF
33 int fill; /* filler lines */
34 #endif
35 int height; /* height of added line */
36 } lineoff_T;
38 static void topline_back __ARGS((lineoff_T *lp));
39 static void botline_forw __ARGS((lineoff_T *lp));
40 #ifdef FEAT_DIFF
41 static void botline_topline __ARGS((lineoff_T *lp));
42 static void topline_botline __ARGS((lineoff_T *lp));
43 static void max_topfill __ARGS((void));
44 #endif
47 * Compute wp->w_botline for the current wp->w_topline. Can be called after
48 * wp->w_topline changed.
50 static void
51 comp_botline(wp)
52 win_T *wp;
54 int n;
55 linenr_T lnum;
56 int done;
57 #ifdef FEAT_FOLDING
58 linenr_T last;
59 int folded;
60 #endif
63 * If w_cline_row is valid, start there.
64 * Otherwise have to start at w_topline.
66 check_cursor_moved(wp);
67 if (wp->w_valid & VALID_CROW)
69 lnum = wp->w_cursor.lnum;
70 done = wp->w_cline_row;
72 else
74 lnum = wp->w_topline;
75 done = 0;
78 for ( ; lnum <= wp->w_buffer->b_ml.ml_line_count; ++lnum)
80 #ifdef FEAT_FOLDING
81 last = lnum;
82 folded = FALSE;
83 if (hasFoldingWin(wp, lnum, NULL, &last, TRUE, NULL))
85 n = 1;
86 folded = TRUE;
88 else
89 #endif
90 #ifdef FEAT_DIFF
91 if (lnum == wp->w_topline)
92 n = plines_win_nofill(wp, lnum, TRUE) + wp->w_topfill;
93 else
94 #endif
95 n = plines_win(wp, lnum, TRUE);
96 if (
97 #ifdef FEAT_FOLDING
98 lnum <= wp->w_cursor.lnum && last >= wp->w_cursor.lnum
99 #else
100 lnum == wp->w_cursor.lnum
101 #endif
104 wp->w_cline_row = done;
105 wp->w_cline_height = n;
106 #ifdef FEAT_FOLDING
107 wp->w_cline_folded = folded;
108 #endif
109 wp->w_valid |= (VALID_CROW|VALID_CHEIGHT);
111 if (done + n > wp->w_height)
112 break;
113 done += n;
114 #ifdef FEAT_FOLDING
115 lnum = last;
116 #endif
119 /* wp->w_botline is the line that is just below the window */
120 wp->w_botline = lnum;
121 wp->w_valid |= VALID_BOTLINE|VALID_BOTLINE_AP;
123 set_empty_rows(wp, done);
127 * Update curwin->w_topline and redraw if necessary.
128 * Used to update the screen before printing a message.
130 void
131 update_topline_redraw()
133 update_topline();
134 if (must_redraw)
135 update_screen(0);
139 * Update curwin->w_topline to move the cursor onto the screen.
141 void
142 update_topline()
144 long line_count;
145 int halfheight;
146 int n;
147 linenr_T old_topline;
148 #ifdef FEAT_DIFF
149 int old_topfill;
150 #endif
151 #ifdef FEAT_FOLDING
152 linenr_T lnum;
153 #endif
154 int check_topline = FALSE;
155 int check_botline = FALSE;
156 #ifdef FEAT_MOUSE
157 int save_so = p_so;
158 #endif
160 if (!screen_valid(TRUE))
161 return;
163 check_cursor_moved(curwin);
164 if (curwin->w_valid & VALID_TOPLINE)
165 return;
167 #ifdef FEAT_MOUSE
168 /* When dragging with the mouse, don't scroll that quickly */
169 if (mouse_dragging > 0)
170 p_so = mouse_dragging - 1;
171 #endif
173 old_topline = curwin->w_topline;
174 #ifdef FEAT_DIFF
175 old_topfill = curwin->w_topfill;
176 #endif
179 * If the buffer is empty, always set topline to 1.
181 if (bufempty()) /* special case - file is empty */
183 if (curwin->w_topline != 1)
184 redraw_later(NOT_VALID);
185 curwin->w_topline = 1;
186 curwin->w_botline = 2;
187 curwin->w_valid |= VALID_BOTLINE|VALID_BOTLINE_AP;
188 #ifdef FEAT_SCROLLBIND
189 curwin->w_scbind_pos = 1;
190 #endif
194 * If the cursor is above or near the top of the window, scroll the window
195 * to show the line the cursor is in, with 'scrolloff' context.
197 else
199 if (curwin->w_topline > 1)
201 /* If the cursor is above topline, scrolling is always needed.
202 * If the cursor is far below topline and there is no folding,
203 * scrolling down is never needed. */
204 if (curwin->w_cursor.lnum < curwin->w_topline)
205 check_topline = TRUE;
206 else if (check_top_offset())
207 check_topline = TRUE;
209 #ifdef FEAT_DIFF
210 /* Check if there are more filler lines than allowed. */
211 if (!check_topline && curwin->w_topfill > diff_check_fill(curwin,
212 curwin->w_topline))
213 check_topline = TRUE;
214 #endif
216 if (check_topline)
218 halfheight = curwin->w_height / 2 - 1;
219 if (halfheight < 2)
220 halfheight = 2;
222 #ifdef FEAT_FOLDING
223 if (hasAnyFolding(curwin))
225 /* Count the number of logical lines between the cursor and
226 * topline + p_so (approximation of how much will be
227 * scrolled). */
228 n = 0;
229 for (lnum = curwin->w_cursor.lnum;
230 lnum < curwin->w_topline + p_so; ++lnum)
232 ++n;
233 /* stop at end of file or when we know we are far off */
234 if (lnum >= curbuf->b_ml.ml_line_count || n >= halfheight)
235 break;
236 (void)hasFolding(lnum, NULL, &lnum);
239 else
240 #endif
241 n = curwin->w_topline + p_so - curwin->w_cursor.lnum;
243 /* If we weren't very close to begin with, we scroll to put the
244 * cursor in the middle of the window. Otherwise put the cursor
245 * near the top of the window. */
246 if (n >= halfheight)
247 scroll_cursor_halfway(FALSE);
248 else
250 scroll_cursor_top(scrolljump_value(), FALSE);
251 check_botline = TRUE;
255 else
257 #ifdef FEAT_FOLDING
258 /* Make sure topline is the first line of a fold. */
259 (void)hasFolding(curwin->w_topline, &curwin->w_topline, NULL);
260 #endif
261 check_botline = TRUE;
266 * If the cursor is below the bottom of the window, scroll the window
267 * to put the cursor on the window.
268 * When w_botline is invalid, recompute it first, to avoid a redraw later.
269 * If w_botline was approximated, we might need a redraw later in a few
270 * cases, but we don't want to spend (a lot of) time recomputing w_botline
271 * for every small change.
273 if (check_botline)
275 if (!(curwin->w_valid & VALID_BOTLINE_AP))
276 validate_botline();
278 if (curwin->w_botline <= curbuf->b_ml.ml_line_count)
280 if (curwin->w_cursor.lnum < curwin->w_botline)
282 if (((long)curwin->w_cursor.lnum
283 >= (long)curwin->w_botline - p_so
284 #ifdef FEAT_FOLDING
285 || hasAnyFolding(curwin)
286 #endif
289 lineoff_T loff;
291 /* Cursor is (a few lines) above botline, check if there are
292 * 'scrolloff' window lines below the cursor. If not, need to
293 * scroll. */
294 n = curwin->w_empty_rows;
295 loff.lnum = curwin->w_cursor.lnum;
296 #ifdef FEAT_FOLDING
297 /* In a fold go to its last line. */
298 (void)hasFolding(loff.lnum, NULL, &loff.lnum);
299 #endif
300 #ifdef FEAT_DIFF
301 loff.fill = 0;
302 n += curwin->w_filler_rows;
303 #endif
304 loff.height = 0;
305 while (loff.lnum < curwin->w_botline
306 #ifdef FEAT_DIFF
307 && (loff.lnum + 1 < curwin->w_botline || loff.fill == 0)
308 #endif
311 n += loff.height;
312 if (n >= p_so)
313 break;
314 botline_forw(&loff);
316 if (n >= p_so)
317 /* sufficient context, no need to scroll */
318 check_botline = FALSE;
320 else
321 /* sufficient context, no need to scroll */
322 check_botline = FALSE;
324 if (check_botline)
326 #ifdef FEAT_FOLDING
327 if (hasAnyFolding(curwin))
329 /* Count the number of logical lines between the cursor and
330 * botline - p_so (approximation of how much will be
331 * scrolled). */
332 line_count = 0;
333 for (lnum = curwin->w_cursor.lnum;
334 lnum >= curwin->w_botline - p_so; --lnum)
336 ++line_count;
337 /* stop at end of file or when we know we are far off */
338 if (lnum <= 0 || line_count > curwin->w_height + 1)
339 break;
340 (void)hasFolding(lnum, &lnum, NULL);
343 else
344 #endif
345 line_count = curwin->w_cursor.lnum - curwin->w_botline
346 + 1 + p_so;
347 if (line_count <= curwin->w_height + 1)
348 scroll_cursor_bot(scrolljump_value(), FALSE);
349 else
350 scroll_cursor_halfway(FALSE);
354 curwin->w_valid |= VALID_TOPLINE;
357 * Need to redraw when topline changed.
359 if (curwin->w_topline != old_topline
360 #ifdef FEAT_DIFF
361 || curwin->w_topfill != old_topfill
362 #endif
365 dollar_vcol = 0;
366 if (curwin->w_skipcol != 0)
368 curwin->w_skipcol = 0;
369 redraw_later(NOT_VALID);
371 else
372 redraw_later(VALID);
373 /* May need to set w_skipcol when cursor in w_topline. */
374 if (curwin->w_cursor.lnum == curwin->w_topline)
375 validate_cursor();
378 #ifdef FEAT_MOUSE
379 p_so = save_so;
380 #endif
384 * Return the scrolljump value to use for the current window.
385 * When 'scrolljump' is positive use it as-is.
386 * When 'scrolljump' is negative use it as a percentage of the window height.
388 static int
389 scrolljump_value()
391 if (p_sj >= 0)
392 return (int)p_sj;
393 return (curwin->w_height * -p_sj) / 100;
397 * Return TRUE when there are not 'scrolloff' lines above the cursor for the
398 * current window.
400 static int
401 check_top_offset()
403 lineoff_T loff;
404 int n;
406 if (curwin->w_cursor.lnum < curwin->w_topline + p_so
407 #ifdef FEAT_FOLDING
408 || hasAnyFolding(curwin)
409 #endif
412 loff.lnum = curwin->w_cursor.lnum;
413 #ifdef FEAT_DIFF
414 loff.fill = 0;
415 n = curwin->w_topfill; /* always have this context */
416 #else
417 n = 0;
418 #endif
419 /* Count the visible screen lines above the cursor line. */
420 while (n < p_so)
422 topline_back(&loff);
423 /* Stop when included a line above the window. */
424 if (loff.lnum < curwin->w_topline
425 #ifdef FEAT_DIFF
426 || (loff.lnum == curwin->w_topline && loff.fill > 0)
427 #endif
429 break;
430 n += loff.height;
432 if (n < p_so)
433 return TRUE;
435 return FALSE;
438 void
439 update_curswant()
441 if (curwin->w_set_curswant)
443 validate_virtcol();
444 curwin->w_curswant = curwin->w_virtcol;
445 curwin->w_set_curswant = FALSE;
450 * Check if the cursor has moved. Set the w_valid flag accordingly.
452 void
453 check_cursor_moved(wp)
454 win_T *wp;
456 if (wp->w_cursor.lnum != wp->w_valid_cursor.lnum)
458 wp->w_valid &= ~(VALID_WROW|VALID_WCOL|VALID_VIRTCOL
459 |VALID_CHEIGHT|VALID_CROW|VALID_TOPLINE);
460 wp->w_valid_cursor = wp->w_cursor;
461 wp->w_valid_leftcol = wp->w_leftcol;
463 else if (wp->w_cursor.col != wp->w_valid_cursor.col
464 || wp->w_leftcol != wp->w_valid_leftcol
465 #ifdef FEAT_VIRTUALEDIT
466 || wp->w_cursor.coladd != wp->w_valid_cursor.coladd
467 #endif
470 wp->w_valid &= ~(VALID_WROW|VALID_WCOL|VALID_VIRTCOL);
471 wp->w_valid_cursor.col = wp->w_cursor.col;
472 wp->w_valid_leftcol = wp->w_leftcol;
473 #ifdef FEAT_VIRTUALEDIT
474 wp->w_valid_cursor.coladd = wp->w_cursor.coladd;
475 #endif
480 * Call this function when some window settings have changed, which require
481 * the cursor position, botline and topline to be recomputed and the window to
482 * be redrawn. E.g, when changing the 'wrap' option or folding.
484 void
485 changed_window_setting()
487 changed_window_setting_win(curwin);
490 void
491 changed_window_setting_win(wp)
492 win_T *wp;
494 wp->w_lines_valid = 0;
495 changed_line_abv_curs_win(wp);
496 wp->w_valid &= ~(VALID_BOTLINE|VALID_BOTLINE_AP|VALID_TOPLINE);
497 redraw_win_later(wp, NOT_VALID);
501 * Set wp->w_topline to a certain number.
503 void
504 set_topline(wp, lnum)
505 win_T *wp;
506 linenr_T lnum;
508 #ifdef FEAT_FOLDING
509 /* go to first of folded lines */
510 (void)hasFoldingWin(wp, lnum, &lnum, NULL, TRUE, NULL);
511 #endif
512 /* Approximate the value of w_botline */
513 wp->w_botline += lnum - wp->w_topline;
514 wp->w_topline = lnum;
515 #ifdef FEAT_AUTOCMD
516 wp->w_topline_was_set = TRUE;
517 #endif
518 #ifdef FEAT_DIFF
519 wp->w_topfill = 0;
520 #endif
521 wp->w_valid &= ~(VALID_WROW|VALID_CROW|VALID_BOTLINE|VALID_TOPLINE);
522 /* Don't set VALID_TOPLINE here, 'scrolloff' needs to be checked. */
523 redraw_later(VALID);
527 * Call this function when the length of the cursor line (in screen
528 * characters) has changed, and the change is before the cursor.
529 * Need to take care of w_botline separately!
531 void
532 changed_cline_bef_curs()
534 curwin->w_valid &= ~(VALID_WROW|VALID_WCOL|VALID_VIRTCOL
535 |VALID_CHEIGHT|VALID_TOPLINE);
538 void
539 changed_cline_bef_curs_win(wp)
540 win_T *wp;
542 wp->w_valid &= ~(VALID_WROW|VALID_WCOL|VALID_VIRTCOL
543 |VALID_CHEIGHT|VALID_TOPLINE);
546 #if 0 /* not used */
548 * Call this function when the length of the cursor line (in screen
549 * characters) has changed, and the position of the cursor doesn't change.
550 * Need to take care of w_botline separately!
552 void
553 changed_cline_aft_curs()
555 curwin->w_valid &= ~VALID_CHEIGHT;
557 #endif
560 * Call this function when the length of a line (in screen characters) above
561 * the cursor have changed.
562 * Need to take care of w_botline separately!
564 void
565 changed_line_abv_curs()
567 curwin->w_valid &= ~(VALID_WROW|VALID_WCOL|VALID_VIRTCOL|VALID_CROW
568 |VALID_CHEIGHT|VALID_TOPLINE);
571 void
572 changed_line_abv_curs_win(wp)
573 win_T *wp;
575 wp->w_valid &= ~(VALID_WROW|VALID_WCOL|VALID_VIRTCOL|VALID_CROW
576 |VALID_CHEIGHT|VALID_TOPLINE);
580 * Make sure the value of curwin->w_botline is valid.
582 void
583 validate_botline()
585 if (!(curwin->w_valid & VALID_BOTLINE))
586 comp_botline(curwin);
590 * Make sure the value of wp->w_botline is valid.
592 static void
593 validate_botline_win(wp)
594 win_T *wp;
596 if (!(wp->w_valid & VALID_BOTLINE))
597 comp_botline(wp);
601 * Mark curwin->w_botline as invalid (because of some change in the buffer).
603 void
604 invalidate_botline()
606 curwin->w_valid &= ~(VALID_BOTLINE|VALID_BOTLINE_AP);
609 void
610 invalidate_botline_win(wp)
611 win_T *wp;
613 wp->w_valid &= ~(VALID_BOTLINE|VALID_BOTLINE_AP);
616 #if 0 /* never used */
618 * Mark curwin->w_botline as approximated (because of some small change in the
619 * buffer).
621 void
622 approximate_botline()
624 curwin->w_valid &= ~VALID_BOTLINE;
626 #endif
628 void
629 approximate_botline_win(wp)
630 win_T *wp;
632 wp->w_valid &= ~VALID_BOTLINE;
635 #if 0 /* not used */
637 * Return TRUE if curwin->w_botline is valid.
640 botline_valid()
642 return (curwin->w_valid & VALID_BOTLINE);
644 #endif
646 #if 0 /* not used */
648 * Return TRUE if curwin->w_botline is valid or approximated.
651 botline_approximated()
653 return (curwin->w_valid & VALID_BOTLINE_AP);
655 #endif
658 * Return TRUE if curwin->w_wrow and curwin->w_wcol are valid.
661 cursor_valid()
663 check_cursor_moved(curwin);
664 return ((curwin->w_valid & (VALID_WROW|VALID_WCOL)) ==
665 (VALID_WROW|VALID_WCOL));
669 * Validate cursor position. Makes sure w_wrow and w_wcol are valid.
670 * w_topline must be valid, you may need to call update_topline() first!
672 void
673 validate_cursor()
675 check_cursor_moved(curwin);
676 if ((curwin->w_valid & (VALID_WCOL|VALID_WROW)) != (VALID_WCOL|VALID_WROW))
677 curs_columns(TRUE);
680 #if defined(FEAT_GUI) || defined(PROTO)
682 * validate w_cline_row.
684 void
685 validate_cline_row()
688 * First make sure that w_topline is valid (after moving the cursor).
690 update_topline();
691 check_cursor_moved(curwin);
692 if (!(curwin->w_valid & VALID_CROW))
693 curs_rows(curwin, FALSE);
695 #endif
698 * Compute wp->w_cline_row and wp->w_cline_height, based on the current value
699 * of wp->w_topine.
701 * Returns OK when cursor is in the window, FAIL when it isn't.
703 static void
704 curs_rows(wp, do_botline)
705 win_T *wp;
706 int do_botline; /* also compute w_botline */
708 linenr_T lnum;
709 int i;
710 int all_invalid;
711 int valid;
712 #ifdef FEAT_FOLDING
713 long fold_count;
714 #endif
716 /* Check if wp->w_lines[].wl_size is invalid */
717 all_invalid = (!redrawing()
718 || wp->w_lines_valid == 0
719 || wp->w_lines[0].wl_lnum > wp->w_topline);
720 i = 0;
721 wp->w_cline_row = 0;
722 for (lnum = wp->w_topline; lnum < wp->w_cursor.lnum; ++i)
724 valid = FALSE;
725 if (!all_invalid && i < wp->w_lines_valid)
727 if (wp->w_lines[i].wl_lnum < lnum || !wp->w_lines[i].wl_valid)
728 continue; /* skip changed or deleted lines */
729 if (wp->w_lines[i].wl_lnum == lnum)
731 #ifdef FEAT_FOLDING
732 /* Check for newly inserted lines below this row, in which
733 * case we need to check for folded lines. */
734 if (!wp->w_buffer->b_mod_set
735 || wp->w_lines[i].wl_lastlnum < wp->w_cursor.lnum
736 || wp->w_buffer->b_mod_top
737 > wp->w_lines[i].wl_lastlnum + 1)
738 #endif
739 valid = TRUE;
741 else if (wp->w_lines[i].wl_lnum > lnum)
742 --i; /* hold at inserted lines */
744 if (valid
745 #ifdef FEAT_DIFF
746 && (lnum != wp->w_topline || !wp->w_p_diff)
747 #endif
750 #ifdef FEAT_FOLDING
751 lnum = wp->w_lines[i].wl_lastlnum + 1;
752 /* Cursor inside folded lines, don't count this row */
753 if (lnum > wp->w_cursor.lnum)
754 break;
755 #else
756 ++lnum;
757 #endif
758 wp->w_cline_row += wp->w_lines[i].wl_size;
760 else
762 #ifdef FEAT_FOLDING
763 fold_count = foldedCount(wp, lnum, NULL);
764 if (fold_count)
766 lnum += fold_count;
767 if (lnum > wp->w_cursor.lnum)
768 break;
769 ++wp->w_cline_row;
771 else
772 #endif
773 #ifdef FEAT_DIFF
774 if (lnum == wp->w_topline)
775 wp->w_cline_row += plines_win_nofill(wp, lnum++, TRUE)
776 + wp->w_topfill;
777 else
778 #endif
779 wp->w_cline_row += plines_win(wp, lnum++, TRUE);
783 check_cursor_moved(wp);
784 if (!(wp->w_valid & VALID_CHEIGHT))
786 if (all_invalid
787 || i == wp->w_lines_valid
788 || (i < wp->w_lines_valid
789 && (!wp->w_lines[i].wl_valid
790 || wp->w_lines[i].wl_lnum != wp->w_cursor.lnum)))
792 #ifdef FEAT_DIFF
793 if (wp->w_cursor.lnum == wp->w_topline)
794 wp->w_cline_height = plines_win_nofill(wp, wp->w_cursor.lnum,
795 TRUE) + wp->w_topfill;
796 else
797 #endif
798 wp->w_cline_height = plines_win(wp, wp->w_cursor.lnum, TRUE);
799 #ifdef FEAT_FOLDING
800 wp->w_cline_folded = hasFoldingWin(wp, wp->w_cursor.lnum,
801 NULL, NULL, TRUE, NULL);
802 #endif
804 else if (i > wp->w_lines_valid)
806 /* a line that is too long to fit on the last screen line */
807 wp->w_cline_height = 0;
808 #ifdef FEAT_FOLDING
809 wp->w_cline_folded = hasFoldingWin(wp, wp->w_cursor.lnum,
810 NULL, NULL, TRUE, NULL);
811 #endif
813 else
815 wp->w_cline_height = wp->w_lines[i].wl_size;
816 #ifdef FEAT_FOLDING
817 wp->w_cline_folded = wp->w_lines[i].wl_folded;
818 #endif
822 wp->w_valid |= VALID_CROW|VALID_CHEIGHT;
824 /* validate botline too, if update_screen doesn't do it */
825 if (do_botline && all_invalid)
826 validate_botline_win(wp);
830 * Validate curwin->w_virtcol only.
832 void
833 validate_virtcol()
835 validate_virtcol_win(curwin);
839 * Validate wp->w_virtcol only.
841 void
842 validate_virtcol_win(wp)
843 win_T *wp;
845 check_cursor_moved(wp);
846 if (!(wp->w_valid & VALID_VIRTCOL))
848 getvvcol(wp, &wp->w_cursor, NULL, &(wp->w_virtcol), NULL);
849 wp->w_valid |= VALID_VIRTCOL;
850 #ifdef FEAT_SYN_HL
851 if (wp->w_p_cuc
852 # ifdef FEAT_INS_EXPAND
853 && !pum_visible()
854 # endif
856 redraw_win_later(wp, SOME_VALID);
857 #endif
862 * Validate curwin->w_cline_height only.
864 static void
865 validate_cheight()
867 check_cursor_moved(curwin);
868 if (!(curwin->w_valid & VALID_CHEIGHT))
870 #ifdef FEAT_DIFF
871 if (curwin->w_cursor.lnum == curwin->w_topline)
872 curwin->w_cline_height = plines_nofill(curwin->w_cursor.lnum)
873 + curwin->w_topfill;
874 else
875 #endif
876 curwin->w_cline_height = plines(curwin->w_cursor.lnum);
877 #ifdef FEAT_FOLDING
878 curwin->w_cline_folded = hasFolding(curwin->w_cursor.lnum, NULL, NULL);
879 #endif
880 curwin->w_valid |= VALID_CHEIGHT;
885 * Validate w_wcol and w_virtcol only.
887 void
888 validate_cursor_col()
890 colnr_T off;
891 colnr_T col;
892 int width;
894 validate_virtcol();
895 if (!(curwin->w_valid & VALID_WCOL))
897 col = curwin->w_virtcol;
898 off = curwin_col_off();
899 col += off;
900 width = W_WIDTH(curwin) - off + curwin_col_off2();
902 /* long line wrapping, adjust curwin->w_wrow */
903 if (curwin->w_p_wrap
904 && col >= (colnr_T)W_WIDTH(curwin)
905 && width > 0)
906 /* use same formula as what is used in curs_columns() */
907 col -= ((col - W_WIDTH(curwin)) / width + 1) * width;
908 if (col > (int)curwin->w_leftcol)
909 col -= curwin->w_leftcol;
910 else
911 col = 0;
912 curwin->w_wcol = col;
914 curwin->w_valid |= VALID_WCOL;
919 * Compute offset of a window, occupied by absolute or relative line number,
920 * fold column and sign column (these don't move when scrolling horizontally).
923 win_col_off(wp)
924 win_T *wp;
926 return (((wp->w_p_nu || wp->w_p_rnu) ? number_width(wp) + 1 : 0)
927 #ifdef FEAT_CMDWIN
928 + (cmdwin_type == 0 || wp != curwin ? 0 : 1)
929 #endif
930 #ifdef FEAT_FOLDING
931 + wp->w_p_fdc
932 #endif
933 #ifdef FEAT_SIGNS
935 # ifdef FEAT_NETBEANS_INTG
936 /* always show glyph gutter in netbeans */
937 usingNetbeans ||
938 # endif
939 wp->w_buffer->b_signlist != NULL ? 2 : 0)
940 #endif
945 curwin_col_off()
947 return win_col_off(curwin);
951 * Return the difference in column offset for the second screen line of a
952 * wrapped line. It's 8 if 'number' or 'relativenumber' is on and 'n' is in
953 * 'cpoptions'.
956 win_col_off2(wp)
957 win_T *wp;
959 if ((wp->w_p_nu || wp->w_p_rnu) && vim_strchr(p_cpo, CPO_NUMCOL) != NULL)
960 return number_width(wp) + 1;
961 return 0;
965 curwin_col_off2()
967 return win_col_off2(curwin);
971 * compute curwin->w_wcol and curwin->w_virtcol.
972 * Also updates curwin->w_wrow and curwin->w_cline_row.
973 * Also updates curwin->w_leftcol.
975 void
976 curs_columns(scroll)
977 int scroll; /* when TRUE, may scroll horizontally */
979 int diff;
980 int extra; /* offset for first screen line */
981 int off_left, off_right;
982 int n;
983 int p_lines;
984 int width = 0;
985 int textwidth;
986 int new_leftcol;
987 colnr_T startcol;
988 colnr_T endcol;
989 colnr_T prev_skipcol;
992 * First make sure that w_topline is valid (after moving the cursor).
994 update_topline();
997 * Next make sure that w_cline_row is valid.
999 if (!(curwin->w_valid & VALID_CROW))
1000 curs_rows(curwin, FALSE);
1003 * Compute the number of virtual columns.
1005 #ifdef FEAT_FOLDING
1006 if (curwin->w_cline_folded)
1007 /* In a folded line the cursor is always in the first column */
1008 startcol = curwin->w_virtcol = endcol = curwin->w_leftcol;
1009 else
1010 #endif
1011 getvvcol(curwin, &curwin->w_cursor,
1012 &startcol, &(curwin->w_virtcol), &endcol);
1014 /* remove '$' from change command when cursor moves onto it */
1015 if (startcol > dollar_vcol)
1016 dollar_vcol = 0;
1018 extra = curwin_col_off();
1019 curwin->w_wcol = curwin->w_virtcol + extra;
1020 endcol += extra;
1023 * Now compute w_wrow, counting screen lines from w_cline_row.
1025 curwin->w_wrow = curwin->w_cline_row;
1027 textwidth = W_WIDTH(curwin) - extra;
1028 if (textwidth <= 0)
1030 /* No room for text, put cursor in last char of window. */
1031 curwin->w_wcol = W_WIDTH(curwin) - 1;
1032 curwin->w_wrow = curwin->w_height - 1;
1034 else if (curwin->w_p_wrap
1035 #ifdef FEAT_VERTSPLIT
1036 && curwin->w_width != 0
1037 #endif
1040 width = textwidth + curwin_col_off2();
1042 /* long line wrapping, adjust curwin->w_wrow */
1043 if (curwin->w_wcol >= W_WIDTH(curwin))
1045 /* this same formula is used in validate_cursor_col() */
1046 n = (curwin->w_wcol - W_WIDTH(curwin)) / width + 1;
1047 curwin->w_wcol -= n * width;
1048 curwin->w_wrow += n;
1050 #ifdef FEAT_LINEBREAK
1051 /* When cursor wraps to first char of next line in Insert
1052 * mode, the 'showbreak' string isn't shown, backup to first
1053 * column */
1054 if (*p_sbr && *ml_get_cursor() == NUL
1055 && curwin->w_wcol == (int)vim_strsize(p_sbr))
1056 curwin->w_wcol = 0;
1057 #endif
1061 /* No line wrapping: compute curwin->w_leftcol if scrolling is on and line
1062 * is not folded.
1063 * If scrolling is off, curwin->w_leftcol is assumed to be 0 */
1064 else if (scroll
1065 #ifdef FEAT_FOLDING
1066 && !curwin->w_cline_folded
1067 #endif
1071 * If Cursor is left of the screen, scroll rightwards.
1072 * If Cursor is right of the screen, scroll leftwards
1073 * If we get closer to the edge than 'sidescrolloff', scroll a little
1074 * extra
1076 off_left = (int)startcol - (int)curwin->w_leftcol - p_siso;
1077 off_right = (int)endcol - (int)(curwin->w_leftcol + W_WIDTH(curwin)
1078 - p_siso) + 1;
1079 if (off_left < 0 || off_right > 0)
1081 if (off_left < 0)
1082 diff = -off_left;
1083 else
1084 diff = off_right;
1086 /* When far off or not enough room on either side, put cursor in
1087 * middle of window. */
1088 if (p_ss == 0 || diff >= textwidth / 2 || off_right >= off_left)
1089 new_leftcol = curwin->w_wcol - extra - textwidth / 2;
1090 else
1092 if (diff < p_ss)
1093 diff = p_ss;
1094 if (off_left < 0)
1095 new_leftcol = curwin->w_leftcol - diff;
1096 else
1097 new_leftcol = curwin->w_leftcol + diff;
1099 if (new_leftcol < 0)
1100 new_leftcol = 0;
1101 if (new_leftcol != (int)curwin->w_leftcol)
1103 curwin->w_leftcol = new_leftcol;
1104 /* screen has to be redrawn with new curwin->w_leftcol */
1105 redraw_later(NOT_VALID);
1108 curwin->w_wcol -= curwin->w_leftcol;
1110 else if (curwin->w_wcol > (int)curwin->w_leftcol)
1111 curwin->w_wcol -= curwin->w_leftcol;
1112 else
1113 curwin->w_wcol = 0;
1115 #ifdef FEAT_DIFF
1116 /* Skip over filler lines. At the top use w_topfill, there
1117 * may be some filler lines above the window. */
1118 if (curwin->w_cursor.lnum == curwin->w_topline)
1119 curwin->w_wrow += curwin->w_topfill;
1120 else
1121 curwin->w_wrow += diff_check_fill(curwin, curwin->w_cursor.lnum);
1122 #endif
1124 prev_skipcol = curwin->w_skipcol;
1126 p_lines = 0;
1127 if ((curwin->w_wrow >= curwin->w_height
1128 || ((prev_skipcol > 0
1129 || curwin->w_wrow + p_so >= curwin->w_height)
1130 && (p_lines =
1131 #ifdef FEAT_DIFF
1132 plines_win_nofill
1133 #else
1134 plines_win
1135 #endif
1136 (curwin, curwin->w_cursor.lnum, FALSE))
1137 - 1 >= curwin->w_height))
1138 && curwin->w_height != 0
1139 && curwin->w_cursor.lnum == curwin->w_topline
1140 && width > 0
1141 #ifdef FEAT_VERTSPLIT
1142 && curwin->w_width != 0
1143 #endif
1146 /* Cursor past end of screen. Happens with a single line that does
1147 * not fit on screen. Find a skipcol to show the text around the
1148 * cursor. Avoid scrolling all the time. compute value of "extra":
1149 * 1: Less than "p_so" lines above
1150 * 2: Less than "p_so" lines below
1151 * 3: both of them */
1152 extra = 0;
1153 if (curwin->w_skipcol + p_so * width > curwin->w_virtcol)
1154 extra = 1;
1155 /* Compute last display line of the buffer line that we want at the
1156 * bottom of the window. */
1157 if (p_lines == 0)
1158 p_lines = plines_win(curwin, curwin->w_cursor.lnum, FALSE);
1159 --p_lines;
1160 if (p_lines > curwin->w_wrow + p_so)
1161 n = curwin->w_wrow + p_so;
1162 else
1163 n = p_lines;
1164 if ((colnr_T)n >= curwin->w_height + curwin->w_skipcol / width)
1165 extra += 2;
1167 if (extra == 3 || p_lines < p_so * 2)
1169 /* not enough room for 'scrolloff', put cursor in the middle */
1170 n = curwin->w_virtcol / width;
1171 if (n > curwin->w_height / 2)
1172 n -= curwin->w_height / 2;
1173 else
1174 n = 0;
1175 /* don't skip more than necessary */
1176 if (n > p_lines - curwin->w_height + 1)
1177 n = p_lines - curwin->w_height + 1;
1178 curwin->w_skipcol = n * width;
1180 else if (extra == 1)
1182 /* less then 'scrolloff' lines above, decrease skipcol */
1183 extra = (curwin->w_skipcol + p_so * width - curwin->w_virtcol
1184 + width - 1) / width;
1185 if (extra > 0)
1187 if ((colnr_T)(extra * width) > curwin->w_skipcol)
1188 extra = curwin->w_skipcol / width;
1189 curwin->w_skipcol -= extra * width;
1192 else if (extra == 2)
1194 /* less then 'scrolloff' lines below, increase skipcol */
1195 endcol = (n - curwin->w_height + 1) * width;
1196 while (endcol > curwin->w_virtcol)
1197 endcol -= width;
1198 if (endcol > curwin->w_skipcol)
1199 curwin->w_skipcol = endcol;
1202 curwin->w_wrow -= curwin->w_skipcol / width;
1203 if (curwin->w_wrow >= curwin->w_height)
1205 /* small window, make sure cursor is in it */
1206 extra = curwin->w_wrow - curwin->w_height + 1;
1207 curwin->w_skipcol += extra * width;
1208 curwin->w_wrow -= extra;
1211 extra = ((int)prev_skipcol - (int)curwin->w_skipcol) / width;
1212 if (extra > 0)
1213 win_ins_lines(curwin, 0, extra, FALSE, FALSE);
1214 else if (extra < 0)
1215 win_del_lines(curwin, 0, -extra, FALSE, FALSE);
1217 else
1218 curwin->w_skipcol = 0;
1219 if (prev_skipcol != curwin->w_skipcol)
1220 redraw_later(NOT_VALID);
1222 /* Redraw when w_row changes and 'relativenumber' is set */
1223 if (((curwin->w_valid & VALID_WROW) == 0 && (curwin->w_p_rnu
1224 #ifdef FEAT_SYN_HL
1225 /* or when w_row changes and 'cursorline' is set. */
1226 || curwin->w_p_cul
1227 #endif
1229 #ifdef FEAT_SYN_HL
1230 /* or when w_virtcol changes and 'cursorcolumn' is set */
1231 || (curwin->w_p_cuc && (curwin->w_valid & VALID_VIRTCOL) == 0)
1232 #endif
1234 # ifdef FEAT_INS_EXPAND
1235 if (!pum_visible())
1236 # endif
1237 redraw_later(SOME_VALID);
1239 curwin->w_valid |= VALID_WCOL|VALID_WROW|VALID_VIRTCOL;
1243 * Scroll the current window down by "line_count" logical lines. "CTRL-Y"
1245 void
1246 scrolldown(line_count, byfold)
1247 long line_count;
1248 int byfold UNUSED; /* TRUE: count a closed fold as one line */
1250 long done = 0; /* total # of physical lines done */
1251 int wrow;
1252 int moved = FALSE;
1254 #ifdef FEAT_FOLDING
1255 linenr_T first;
1257 /* Make sure w_topline is at the first of a sequence of folded lines. */
1258 (void)hasFolding(curwin->w_topline, &curwin->w_topline, NULL);
1259 #endif
1260 validate_cursor(); /* w_wrow needs to be valid */
1261 while (line_count-- > 0)
1263 #ifdef FEAT_DIFF
1264 if (curwin->w_topfill < diff_check(curwin, curwin->w_topline)
1265 && curwin->w_topfill < curwin->w_height - 1)
1267 ++curwin->w_topfill;
1268 ++done;
1270 else
1271 #endif
1273 if (curwin->w_topline == 1)
1274 break;
1275 --curwin->w_topline;
1276 #ifdef FEAT_DIFF
1277 curwin->w_topfill = 0;
1278 #endif
1279 #ifdef FEAT_FOLDING
1280 /* A sequence of folded lines only counts for one logical line */
1281 if (hasFolding(curwin->w_topline, &first, NULL))
1283 ++done;
1284 if (!byfold)
1285 line_count -= curwin->w_topline - first - 1;
1286 curwin->w_botline -= curwin->w_topline - first;
1287 curwin->w_topline = first;
1289 else
1290 #endif
1291 #ifdef FEAT_DIFF
1292 done += plines_nofill(curwin->w_topline);
1293 #else
1294 done += plines(curwin->w_topline);
1295 #endif
1297 --curwin->w_botline; /* approximate w_botline */
1298 invalidate_botline();
1300 curwin->w_wrow += done; /* keep w_wrow updated */
1301 curwin->w_cline_row += done; /* keep w_cline_row updated */
1303 #ifdef FEAT_DIFF
1304 if (curwin->w_cursor.lnum == curwin->w_topline)
1305 curwin->w_cline_row = 0;
1306 check_topfill(curwin, TRUE);
1307 #endif
1310 * Compute the row number of the last row of the cursor line
1311 * and move the cursor onto the displayed part of the window.
1313 wrow = curwin->w_wrow;
1314 if (curwin->w_p_wrap
1315 #ifdef FEAT_VERTSPLIT
1316 && curwin->w_width != 0
1317 #endif
1320 validate_virtcol();
1321 validate_cheight();
1322 wrow += curwin->w_cline_height - 1 -
1323 curwin->w_virtcol / W_WIDTH(curwin);
1325 while (wrow >= curwin->w_height && curwin->w_cursor.lnum > 1)
1327 #ifdef FEAT_FOLDING
1328 if (hasFolding(curwin->w_cursor.lnum, &first, NULL))
1330 --wrow;
1331 if (first == 1)
1332 curwin->w_cursor.lnum = 1;
1333 else
1334 curwin->w_cursor.lnum = first - 1;
1336 else
1337 #endif
1338 wrow -= plines(curwin->w_cursor.lnum--);
1339 curwin->w_valid &=
1340 ~(VALID_WROW|VALID_WCOL|VALID_CHEIGHT|VALID_CROW|VALID_VIRTCOL);
1341 moved = TRUE;
1343 if (moved)
1345 #ifdef FEAT_FOLDING
1346 /* Move cursor to first line of closed fold. */
1347 foldAdjustCursor();
1348 #endif
1349 coladvance(curwin->w_curswant);
1354 * Scroll the current window up by "line_count" logical lines. "CTRL-E"
1356 void
1357 scrollup(line_count, byfold)
1358 long line_count;
1359 int byfold UNUSED; /* TRUE: count a closed fold as one line */
1361 #if defined(FEAT_FOLDING) || defined(FEAT_DIFF)
1362 linenr_T lnum;
1364 if (
1365 # ifdef FEAT_FOLDING
1366 (byfold && hasAnyFolding(curwin))
1367 # ifdef FEAT_DIFF
1369 # endif
1370 # endif
1371 # ifdef FEAT_DIFF
1372 curwin->w_p_diff
1373 # endif
1376 /* count each sequence of folded lines as one logical line */
1377 lnum = curwin->w_topline;
1378 while (line_count--)
1380 # ifdef FEAT_DIFF
1381 if (curwin->w_topfill > 0)
1382 --curwin->w_topfill;
1383 else
1384 # endif
1386 # ifdef FEAT_FOLDING
1387 if (byfold)
1388 (void)hasFolding(lnum, NULL, &lnum);
1389 # endif
1390 if (lnum >= curbuf->b_ml.ml_line_count)
1391 break;
1392 ++lnum;
1393 # ifdef FEAT_DIFF
1394 curwin->w_topfill = diff_check_fill(curwin, lnum);
1395 # endif
1398 /* approximate w_botline */
1399 curwin->w_botline += lnum - curwin->w_topline;
1400 curwin->w_topline = lnum;
1402 else
1403 #endif
1405 curwin->w_topline += line_count;
1406 curwin->w_botline += line_count; /* approximate w_botline */
1409 if (curwin->w_topline > curbuf->b_ml.ml_line_count)
1410 curwin->w_topline = curbuf->b_ml.ml_line_count;
1411 if (curwin->w_botline > curbuf->b_ml.ml_line_count + 1)
1412 curwin->w_botline = curbuf->b_ml.ml_line_count + 1;
1414 #ifdef FEAT_DIFF
1415 check_topfill(curwin, FALSE);
1416 #endif
1418 #ifdef FEAT_FOLDING
1419 if (hasAnyFolding(curwin))
1420 /* Make sure w_topline is at the first of a sequence of folded lines. */
1421 (void)hasFolding(curwin->w_topline, &curwin->w_topline, NULL);
1422 #endif
1424 curwin->w_valid &= ~(VALID_WROW|VALID_CROW|VALID_BOTLINE);
1425 if (curwin->w_cursor.lnum < curwin->w_topline)
1427 curwin->w_cursor.lnum = curwin->w_topline;
1428 curwin->w_valid &=
1429 ~(VALID_WROW|VALID_WCOL|VALID_CHEIGHT|VALID_CROW|VALID_VIRTCOL);
1430 coladvance(curwin->w_curswant);
1434 #ifdef FEAT_DIFF
1436 * Don't end up with too many filler lines in the window.
1438 void
1439 check_topfill(wp, down)
1440 win_T *wp;
1441 int down; /* when TRUE scroll down when not enough space */
1443 int n;
1445 if (wp->w_topfill > 0)
1447 n = plines_win_nofill(wp, wp->w_topline, TRUE);
1448 if (wp->w_topfill + n > wp->w_height)
1450 if (down && wp->w_topline > 1)
1452 --wp->w_topline;
1453 wp->w_topfill = 0;
1455 else
1457 wp->w_topfill = wp->w_height - n;
1458 if (wp->w_topfill < 0)
1459 wp->w_topfill = 0;
1466 * Use as many filler lines as possible for w_topline. Make sure w_topline
1467 * is still visible.
1469 static void
1470 max_topfill()
1472 int n;
1474 n = plines_nofill(curwin->w_topline);
1475 if (n >= curwin->w_height)
1476 curwin->w_topfill = 0;
1477 else
1479 curwin->w_topfill = diff_check_fill(curwin, curwin->w_topline);
1480 if (curwin->w_topfill + n > curwin->w_height)
1481 curwin->w_topfill = curwin->w_height - n;
1484 #endif
1486 #if defined(FEAT_INS_EXPAND) || defined(PROTO)
1488 * Scroll the screen one line down, but don't do it if it would move the
1489 * cursor off the screen.
1491 void
1492 scrolldown_clamp()
1494 int end_row;
1495 #ifdef FEAT_DIFF
1496 int can_fill = (curwin->w_topfill
1497 < diff_check_fill(curwin, curwin->w_topline));
1498 #endif
1500 if (curwin->w_topline <= 1
1501 #ifdef FEAT_DIFF
1502 && !can_fill
1503 #endif
1505 return;
1507 validate_cursor(); /* w_wrow needs to be valid */
1510 * Compute the row number of the last row of the cursor line
1511 * and make sure it doesn't go off the screen. Make sure the cursor
1512 * doesn't go past 'scrolloff' lines from the screen end.
1514 end_row = curwin->w_wrow;
1515 #ifdef FEAT_DIFF
1516 if (can_fill)
1517 ++end_row;
1518 else
1519 end_row += plines_nofill(curwin->w_topline - 1);
1520 #else
1521 end_row += plines(curwin->w_topline - 1);
1522 #endif
1523 if (curwin->w_p_wrap
1524 #ifdef FEAT_VERTSPLIT
1525 && curwin->w_width != 0
1526 #endif
1529 validate_cheight();
1530 validate_virtcol();
1531 end_row += curwin->w_cline_height - 1 -
1532 curwin->w_virtcol / W_WIDTH(curwin);
1534 if (end_row < curwin->w_height - p_so)
1536 #ifdef FEAT_DIFF
1537 if (can_fill)
1539 ++curwin->w_topfill;
1540 check_topfill(curwin, TRUE);
1542 else
1544 --curwin->w_topline;
1545 curwin->w_topfill = 0;
1547 #else
1548 --curwin->w_topline;
1549 #endif
1550 #ifdef FEAT_FOLDING
1551 hasFolding(curwin->w_topline, &curwin->w_topline, NULL);
1552 #endif
1553 --curwin->w_botline; /* approximate w_botline */
1554 curwin->w_valid &= ~(VALID_WROW|VALID_CROW|VALID_BOTLINE);
1559 * Scroll the screen one line up, but don't do it if it would move the cursor
1560 * off the screen.
1562 void
1563 scrollup_clamp()
1565 int start_row;
1567 if (curwin->w_topline == curbuf->b_ml.ml_line_count
1568 #ifdef FEAT_DIFF
1569 && curwin->w_topfill == 0
1570 #endif
1572 return;
1574 validate_cursor(); /* w_wrow needs to be valid */
1577 * Compute the row number of the first row of the cursor line
1578 * and make sure it doesn't go off the screen. Make sure the cursor
1579 * doesn't go before 'scrolloff' lines from the screen start.
1581 #ifdef FEAT_DIFF
1582 start_row = curwin->w_wrow - plines_nofill(curwin->w_topline)
1583 - curwin->w_topfill;
1584 #else
1585 start_row = curwin->w_wrow - plines(curwin->w_topline);
1586 #endif
1587 if (curwin->w_p_wrap
1588 #ifdef FEAT_VERTSPLIT
1589 && curwin->w_width != 0
1590 #endif
1593 validate_virtcol();
1594 start_row -= curwin->w_virtcol / W_WIDTH(curwin);
1596 if (start_row >= p_so)
1598 #ifdef FEAT_DIFF
1599 if (curwin->w_topfill > 0)
1600 --curwin->w_topfill;
1601 else
1602 #endif
1604 #ifdef FEAT_FOLDING
1605 (void)hasFolding(curwin->w_topline, NULL, &curwin->w_topline);
1606 #endif
1607 ++curwin->w_topline;
1609 ++curwin->w_botline; /* approximate w_botline */
1610 curwin->w_valid &= ~(VALID_WROW|VALID_CROW|VALID_BOTLINE);
1613 #endif /* FEAT_INS_EXPAND */
1616 * Add one line above "lp->lnum". This can be a filler line, a closed fold or
1617 * a (wrapped) text line. Uses and sets "lp->fill".
1618 * Returns the height of the added line in "lp->height".
1619 * Lines above the first one are incredibly high: MAXCOL.
1621 static void
1622 topline_back(lp)
1623 lineoff_T *lp;
1625 #ifdef FEAT_DIFF
1626 if (lp->fill < diff_check_fill(curwin, lp->lnum))
1628 /* Add a filler line. */
1629 ++lp->fill;
1630 lp->height = 1;
1632 else
1633 #endif
1635 --lp->lnum;
1636 #ifdef FEAT_DIFF
1637 lp->fill = 0;
1638 #endif
1639 if (lp->lnum < 1)
1640 lp->height = MAXCOL;
1641 else
1642 #ifdef FEAT_FOLDING
1643 if (hasFolding(lp->lnum, &lp->lnum, NULL))
1644 /* Add a closed fold */
1645 lp->height = 1;
1646 else
1647 #endif
1649 #ifdef FEAT_DIFF
1650 lp->height = plines_nofill(lp->lnum);
1651 #else
1652 lp->height = plines(lp->lnum);
1653 #endif
1659 * Add one line below "lp->lnum". This can be a filler line, a closed fold or
1660 * a (wrapped) text line. Uses and sets "lp->fill".
1661 * Returns the height of the added line in "lp->height".
1662 * Lines below the last one are incredibly high.
1664 static void
1665 botline_forw(lp)
1666 lineoff_T *lp;
1668 #ifdef FEAT_DIFF
1669 if (lp->fill < diff_check_fill(curwin, lp->lnum + 1))
1671 /* Add a filler line. */
1672 ++lp->fill;
1673 lp->height = 1;
1675 else
1676 #endif
1678 ++lp->lnum;
1679 #ifdef FEAT_DIFF
1680 lp->fill = 0;
1681 #endif
1682 if (lp->lnum > curbuf->b_ml.ml_line_count)
1683 lp->height = MAXCOL;
1684 else
1685 #ifdef FEAT_FOLDING
1686 if (hasFolding(lp->lnum, NULL, &lp->lnum))
1687 /* Add a closed fold */
1688 lp->height = 1;
1689 else
1690 #endif
1692 #ifdef FEAT_DIFF
1693 lp->height = plines_nofill(lp->lnum);
1694 #else
1695 lp->height = plines(lp->lnum);
1696 #endif
1701 #ifdef FEAT_DIFF
1703 * Switch from including filler lines below lp->lnum to including filler
1704 * lines above loff.lnum + 1. This keeps pointing to the same line.
1705 * When there are no filler lines nothing changes.
1707 static void
1708 botline_topline(lp)
1709 lineoff_T *lp;
1711 if (lp->fill > 0)
1713 ++lp->lnum;
1714 lp->fill = diff_check_fill(curwin, lp->lnum) - lp->fill + 1;
1719 * Switch from including filler lines above lp->lnum to including filler
1720 * lines below loff.lnum - 1. This keeps pointing to the same line.
1721 * When there are no filler lines nothing changes.
1723 static void
1724 topline_botline(lp)
1725 lineoff_T *lp;
1727 if (lp->fill > 0)
1729 lp->fill = diff_check_fill(curwin, lp->lnum) - lp->fill + 1;
1730 --lp->lnum;
1733 #endif
1736 * Recompute topline to put the cursor at the top of the window.
1737 * Scroll at least "min_scroll" lines.
1738 * If "always" is TRUE, always set topline (for "zt").
1740 void
1741 scroll_cursor_top(min_scroll, always)
1742 int min_scroll;
1743 int always;
1745 int scrolled = 0;
1746 int extra = 0;
1747 int used;
1748 int i;
1749 linenr_T top; /* just above displayed lines */
1750 linenr_T bot; /* just below displayed lines */
1751 linenr_T old_topline = curwin->w_topline;
1752 #ifdef FEAT_DIFF
1753 linenr_T old_topfill = curwin->w_topfill;
1754 #endif
1755 linenr_T new_topline;
1756 int off = p_so;
1758 #ifdef FEAT_MOUSE
1759 if (mouse_dragging > 0)
1760 off = mouse_dragging - 1;
1761 #endif
1764 * Decrease topline until:
1765 * - it has become 1
1766 * - (part of) the cursor line is moved off the screen or
1767 * - moved at least 'scrolljump' lines and
1768 * - at least 'scrolloff' lines above and below the cursor
1770 validate_cheight();
1771 used = curwin->w_cline_height;
1772 if (curwin->w_cursor.lnum < curwin->w_topline)
1773 scrolled = used;
1775 #ifdef FEAT_FOLDING
1776 if (hasFolding(curwin->w_cursor.lnum, &top, &bot))
1778 --top;
1779 ++bot;
1781 else
1782 #endif
1784 top = curwin->w_cursor.lnum - 1;
1785 bot = curwin->w_cursor.lnum + 1;
1787 new_topline = top + 1;
1789 #ifdef FEAT_DIFF
1790 /* count filler lines of the cursor window as context */
1791 i = diff_check_fill(curwin, curwin->w_cursor.lnum);
1792 used += i;
1793 extra += i;
1794 #endif
1797 * Check if the lines from "top" to "bot" fit in the window. If they do,
1798 * set new_topline and advance "top" and "bot" to include more lines.
1800 while (top > 0)
1802 #ifdef FEAT_FOLDING
1803 if (hasFolding(top, &top, NULL))
1804 /* count one logical line for a sequence of folded lines */
1805 i = 1;
1806 else
1807 #endif
1808 i = plines(top);
1809 used += i;
1810 if (extra + i <= off && bot < curbuf->b_ml.ml_line_count)
1812 #ifdef FEAT_FOLDING
1813 if (hasFolding(bot, NULL, &bot))
1814 /* count one logical line for a sequence of folded lines */
1815 ++used;
1816 else
1817 #endif
1818 used += plines(bot);
1820 if (used > curwin->w_height)
1821 break;
1822 if (top < curwin->w_topline)
1823 scrolled += i;
1826 * If scrolling is needed, scroll at least 'sj' lines.
1828 if ((new_topline >= curwin->w_topline || scrolled > min_scroll)
1829 && extra >= off)
1830 break;
1832 extra += i;
1833 new_topline = top;
1834 --top;
1835 ++bot;
1839 * If we don't have enough space, put cursor in the middle.
1840 * This makes sure we get the same position when using "k" and "j"
1841 * in a small window.
1843 if (used > curwin->w_height)
1844 scroll_cursor_halfway(FALSE);
1845 else
1848 * If "always" is FALSE, only adjust topline to a lower value, higher
1849 * value may happen with wrapping lines
1851 if (new_topline < curwin->w_topline || always)
1852 curwin->w_topline = new_topline;
1853 if (curwin->w_topline > curwin->w_cursor.lnum)
1854 curwin->w_topline = curwin->w_cursor.lnum;
1855 #ifdef FEAT_DIFF
1856 curwin->w_topfill = diff_check_fill(curwin, curwin->w_topline);
1857 if (curwin->w_topfill > 0 && extra > off)
1859 curwin->w_topfill -= extra - off;
1860 if (curwin->w_topfill < 0)
1861 curwin->w_topfill = 0;
1863 check_topfill(curwin, FALSE);
1864 #endif
1865 if (curwin->w_topline != old_topline
1866 #ifdef FEAT_DIFF
1867 || curwin->w_topfill != old_topfill
1868 #endif
1870 curwin->w_valid &=
1871 ~(VALID_WROW|VALID_CROW|VALID_BOTLINE|VALID_BOTLINE_AP);
1872 curwin->w_valid |= VALID_TOPLINE;
1877 * Set w_empty_rows and w_filler_rows for window "wp", having used up "used"
1878 * screen lines for text lines.
1880 void
1881 set_empty_rows(wp, used)
1882 win_T *wp;
1883 int used;
1885 #ifdef FEAT_DIFF
1886 wp->w_filler_rows = 0;
1887 #endif
1888 if (used == 0)
1889 wp->w_empty_rows = 0; /* single line that doesn't fit */
1890 else
1892 wp->w_empty_rows = wp->w_height - used;
1893 #ifdef FEAT_DIFF
1894 if (wp->w_botline <= wp->w_buffer->b_ml.ml_line_count)
1896 wp->w_filler_rows = diff_check_fill(wp, wp->w_botline);
1897 if (wp->w_empty_rows > wp->w_filler_rows)
1898 wp->w_empty_rows -= wp->w_filler_rows;
1899 else
1901 wp->w_filler_rows = wp->w_empty_rows;
1902 wp->w_empty_rows = 0;
1905 #endif
1910 * Recompute topline to put the cursor at the bottom of the window.
1911 * Scroll at least "min_scroll" lines.
1912 * If "set_topbot" is TRUE, set topline and botline first (for "zb").
1913 * This is messy stuff!!!
1915 void
1916 scroll_cursor_bot(min_scroll, set_topbot)
1917 int min_scroll;
1918 int set_topbot;
1920 int used;
1921 int scrolled = 0;
1922 int extra = 0;
1923 int i;
1924 linenr_T line_count;
1925 linenr_T old_topline = curwin->w_topline;
1926 lineoff_T loff;
1927 lineoff_T boff;
1928 #ifdef FEAT_DIFF
1929 int old_topfill = curwin->w_topfill;
1930 int fill_below_window;
1931 #endif
1932 linenr_T old_botline = curwin->w_botline;
1933 linenr_T old_valid = curwin->w_valid;
1934 int old_empty_rows = curwin->w_empty_rows;
1935 linenr_T cln; /* Cursor Line Number */
1937 cln = curwin->w_cursor.lnum;
1938 if (set_topbot)
1940 used = 0;
1941 curwin->w_botline = cln + 1;
1942 #ifdef FEAT_DIFF
1943 loff.fill = 0;
1944 #endif
1945 for (curwin->w_topline = curwin->w_botline;
1946 curwin->w_topline > 1;
1947 curwin->w_topline = loff.lnum)
1949 loff.lnum = curwin->w_topline;
1950 topline_back(&loff);
1951 if (loff.height == MAXCOL || used + loff.height > curwin->w_height)
1952 break;
1953 used += loff.height;
1954 #ifdef FEAT_DIFF
1955 curwin->w_topfill = loff.fill;
1956 #endif
1958 set_empty_rows(curwin, used);
1959 curwin->w_valid |= VALID_BOTLINE|VALID_BOTLINE_AP;
1960 if (curwin->w_topline != old_topline
1961 #ifdef FEAT_DIFF
1962 || curwin->w_topfill != old_topfill
1963 #endif
1965 curwin->w_valid &= ~(VALID_WROW|VALID_CROW);
1967 else
1968 validate_botline();
1970 /* The lines of the cursor line itself are always used. */
1971 #ifdef FEAT_DIFF
1972 used = plines_nofill(cln);
1973 #else
1974 validate_cheight();
1975 used = curwin->w_cline_height;
1976 #endif
1978 /* If the cursor is below botline, we will at least scroll by the height
1979 * of the cursor line. Correct for empty lines, which are really part of
1980 * botline. */
1981 if (cln >= curwin->w_botline)
1983 scrolled = used;
1984 if (cln == curwin->w_botline)
1985 scrolled -= curwin->w_empty_rows;
1989 * Stop counting lines to scroll when
1990 * - hitting start of the file
1991 * - scrolled nothing or at least 'sj' lines
1992 * - at least 'so' lines below the cursor
1993 * - lines between botline and cursor have been counted
1995 #ifdef FEAT_FOLDING
1996 if (!hasFolding(curwin->w_cursor.lnum, &loff.lnum, &boff.lnum))
1997 #endif
1999 loff.lnum = cln;
2000 boff.lnum = cln;
2002 #ifdef FEAT_DIFF
2003 loff.fill = 0;
2004 boff.fill = 0;
2005 fill_below_window = diff_check_fill(curwin, curwin->w_botline)
2006 - curwin->w_filler_rows;
2007 #endif
2009 while (loff.lnum > 1)
2011 /* Stop when scrolled nothing or at least "min_scroll", found "extra"
2012 * context for 'scrolloff' and counted all lines below the window. */
2013 if ((((scrolled <= 0 || scrolled >= min_scroll)
2014 && extra >= (
2015 #ifdef FEAT_MOUSE
2016 mouse_dragging > 0 ? mouse_dragging - 1 :
2017 #endif
2018 p_so))
2019 || boff.lnum + 1 > curbuf->b_ml.ml_line_count)
2020 && loff.lnum <= curwin->w_botline
2021 #ifdef FEAT_DIFF
2022 && (loff.lnum < curwin->w_botline
2023 || loff.fill >= fill_below_window)
2024 #endif
2026 break;
2028 /* Add one line above */
2029 topline_back(&loff);
2030 if (loff.height == MAXCOL)
2031 used = MAXCOL;
2032 else
2033 used += loff.height;
2034 if (used > curwin->w_height)
2035 break;
2036 if (loff.lnum >= curwin->w_botline
2037 #ifdef FEAT_DIFF
2038 && (loff.lnum > curwin->w_botline
2039 || loff.fill <= fill_below_window)
2040 #endif
2043 /* Count screen lines that are below the window. */
2044 scrolled += loff.height;
2045 if (loff.lnum == curwin->w_botline
2046 #ifdef FEAT_DIFF
2047 && boff.fill == 0
2048 #endif
2050 scrolled -= curwin->w_empty_rows;
2053 if (boff.lnum < curbuf->b_ml.ml_line_count)
2055 /* Add one line below */
2056 botline_forw(&boff);
2057 used += boff.height;
2058 if (used > curwin->w_height)
2059 break;
2060 if (extra < (
2061 #ifdef FEAT_MOUSE
2062 mouse_dragging > 0 ? mouse_dragging - 1 :
2063 #endif
2064 p_so) || scrolled < min_scroll)
2066 extra += boff.height;
2067 if (boff.lnum >= curwin->w_botline
2068 #ifdef FEAT_DIFF
2069 || (boff.lnum + 1 == curwin->w_botline
2070 && boff.fill > curwin->w_filler_rows)
2071 #endif
2074 /* Count screen lines that are below the window. */
2075 scrolled += boff.height;
2076 if (boff.lnum == curwin->w_botline
2077 #ifdef FEAT_DIFF
2078 && boff.fill == 0
2079 #endif
2081 scrolled -= curwin->w_empty_rows;
2087 /* curwin->w_empty_rows is larger, no need to scroll */
2088 if (scrolled <= 0)
2089 line_count = 0;
2090 /* more than a screenfull, don't scroll but redraw */
2091 else if (used > curwin->w_height)
2092 line_count = used;
2093 /* scroll minimal number of lines */
2094 else
2096 line_count = 0;
2097 #ifdef FEAT_DIFF
2098 boff.fill = curwin->w_topfill;
2099 #endif
2100 boff.lnum = curwin->w_topline - 1;
2101 for (i = 0; i < scrolled && boff.lnum < curwin->w_botline; )
2103 botline_forw(&boff);
2104 i += boff.height;
2105 ++line_count;
2107 if (i < scrolled) /* below curwin->w_botline, don't scroll */
2108 line_count = 9999;
2112 * Scroll up if the cursor is off the bottom of the screen a bit.
2113 * Otherwise put it at 1/2 of the screen.
2115 if (line_count >= curwin->w_height && line_count > min_scroll)
2116 scroll_cursor_halfway(FALSE);
2117 else
2118 scrollup(line_count, TRUE);
2121 * If topline didn't change we need to restore w_botline and w_empty_rows
2122 * (we changed them).
2123 * If topline did change, update_screen() will set botline.
2125 if (curwin->w_topline == old_topline && set_topbot)
2127 curwin->w_botline = old_botline;
2128 curwin->w_empty_rows = old_empty_rows;
2129 curwin->w_valid = old_valid;
2131 curwin->w_valid |= VALID_TOPLINE;
2135 * Recompute topline to put the cursor halfway the window
2136 * If "atend" is TRUE, also put it halfway at the end of the file.
2138 void
2139 scroll_cursor_halfway(atend)
2140 int atend;
2142 int above = 0;
2143 linenr_T topline;
2144 #ifdef FEAT_DIFF
2145 int topfill = 0;
2146 #endif
2147 int below = 0;
2148 int used;
2149 lineoff_T loff;
2150 lineoff_T boff;
2152 loff.lnum = boff.lnum = curwin->w_cursor.lnum;
2153 #ifdef FEAT_FOLDING
2154 (void)hasFolding(loff.lnum, &loff.lnum, &boff.lnum);
2155 #endif
2156 #ifdef FEAT_DIFF
2157 used = plines_nofill(loff.lnum);
2158 loff.fill = 0;
2159 boff.fill = 0;
2160 #else
2161 used = plines(loff.lnum);
2162 #endif
2163 topline = loff.lnum;
2164 while (topline > 1)
2166 if (below <= above) /* add a line below the cursor first */
2168 if (boff.lnum < curbuf->b_ml.ml_line_count)
2170 botline_forw(&boff);
2171 used += boff.height;
2172 if (used > curwin->w_height)
2173 break;
2174 below += boff.height;
2176 else
2178 ++below; /* count a "~" line */
2179 if (atend)
2180 ++used;
2184 if (below > above) /* add a line above the cursor */
2186 topline_back(&loff);
2187 if (loff.height == MAXCOL)
2188 used = MAXCOL;
2189 else
2190 used += loff.height;
2191 if (used > curwin->w_height)
2192 break;
2193 above += loff.height;
2194 topline = loff.lnum;
2195 #ifdef FEAT_DIFF
2196 topfill = loff.fill;
2197 #endif
2200 #ifdef FEAT_FOLDING
2201 if (!hasFolding(topline, &curwin->w_topline, NULL))
2202 #endif
2203 curwin->w_topline = topline;
2204 #ifdef FEAT_DIFF
2205 curwin->w_topfill = topfill;
2206 check_topfill(curwin, FALSE);
2207 #endif
2208 curwin->w_valid &= ~(VALID_WROW|VALID_CROW|VALID_BOTLINE|VALID_BOTLINE_AP);
2209 curwin->w_valid |= VALID_TOPLINE;
2213 * Correct the cursor position so that it is in a part of the screen at least
2214 * 'so' lines from the top and bottom, if possible.
2215 * If not possible, put it at the same position as scroll_cursor_halfway().
2216 * When called topline must be valid!
2218 void
2219 cursor_correct()
2221 int above = 0; /* screen lines above topline */
2222 linenr_T topline;
2223 int below = 0; /* screen lines below botline */
2224 linenr_T botline;
2225 int above_wanted, below_wanted;
2226 linenr_T cln; /* Cursor Line Number */
2227 int max_off;
2230 * How many lines we would like to have above/below the cursor depends on
2231 * whether the first/last line of the file is on screen.
2233 above_wanted = p_so;
2234 below_wanted = p_so;
2235 #ifdef FEAT_MOUSE
2236 if (mouse_dragging > 0)
2238 above_wanted = mouse_dragging - 1;
2239 below_wanted = mouse_dragging - 1;
2241 #endif
2242 if (curwin->w_topline == 1)
2244 above_wanted = 0;
2245 max_off = curwin->w_height / 2;
2246 if (below_wanted > max_off)
2247 below_wanted = max_off;
2249 validate_botline();
2250 if (curwin->w_botline == curbuf->b_ml.ml_line_count + 1
2251 #ifdef FEAT_MOUSE
2252 && mouse_dragging == 0
2253 #endif
2256 below_wanted = 0;
2257 max_off = (curwin->w_height - 1) / 2;
2258 if (above_wanted > max_off)
2259 above_wanted = max_off;
2263 * If there are sufficient file-lines above and below the cursor, we can
2264 * return now.
2266 cln = curwin->w_cursor.lnum;
2267 if (cln >= curwin->w_topline + above_wanted
2268 && cln < curwin->w_botline - below_wanted
2269 #ifdef FEAT_FOLDING
2270 && !hasAnyFolding(curwin)
2271 #endif
2273 return;
2276 * Narrow down the area where the cursor can be put by taking lines from
2277 * the top and the bottom until:
2278 * - the desired context lines are found
2279 * - the lines from the top is past the lines from the bottom
2281 topline = curwin->w_topline;
2282 botline = curwin->w_botline - 1;
2283 #ifdef FEAT_DIFF
2284 /* count filler lines as context */
2285 above = curwin->w_topfill;
2286 below = curwin->w_filler_rows;
2287 #endif
2288 while ((above < above_wanted || below < below_wanted) && topline < botline)
2290 if (below < below_wanted && (below <= above || above >= above_wanted))
2292 #ifdef FEAT_FOLDING
2293 if (hasFolding(botline, &botline, NULL))
2294 ++below;
2295 else
2296 #endif
2297 below += plines(botline);
2298 --botline;
2300 if (above < above_wanted && (above < below || below >= below_wanted))
2302 #ifdef FEAT_FOLDING
2303 if (hasFolding(topline, NULL, &topline))
2304 ++above;
2305 else
2306 #endif
2307 #ifndef FEAT_DIFF
2308 above += plines(topline);
2309 #else
2310 above += plines_nofill(topline);
2312 /* Count filler lines below this line as context. */
2313 if (topline < botline)
2314 above += diff_check_fill(curwin, topline + 1);
2315 #endif
2316 ++topline;
2319 if (topline == botline || botline == 0)
2320 curwin->w_cursor.lnum = topline;
2321 else if (topline > botline)
2322 curwin->w_cursor.lnum = botline;
2323 else
2325 if (cln < topline && curwin->w_topline > 1)
2327 curwin->w_cursor.lnum = topline;
2328 curwin->w_valid &=
2329 ~(VALID_WROW|VALID_WCOL|VALID_CHEIGHT|VALID_CROW);
2331 if (cln > botline && curwin->w_botline <= curbuf->b_ml.ml_line_count)
2333 curwin->w_cursor.lnum = botline;
2334 curwin->w_valid &=
2335 ~(VALID_WROW|VALID_WCOL|VALID_CHEIGHT|VALID_CROW);
2338 curwin->w_valid |= VALID_TOPLINE;
2341 static void get_scroll_overlap __ARGS((lineoff_T *lp, int dir));
2344 * move screen 'count' pages up or down and update screen
2346 * return FAIL for failure, OK otherwise
2349 onepage(dir, count)
2350 int dir;
2351 long count;
2353 long n;
2354 int retval = OK;
2355 lineoff_T loff;
2356 linenr_T old_topline = curwin->w_topline;
2358 if (curbuf->b_ml.ml_line_count == 1) /* nothing to do */
2360 beep_flush();
2361 return FAIL;
2364 for ( ; count > 0; --count)
2366 validate_botline();
2368 * It's an error to move a page up when the first line is already on
2369 * the screen. It's an error to move a page down when the last line
2370 * is on the screen and the topline is 'scrolloff' lines from the
2371 * last line.
2373 if (dir == FORWARD
2374 ? ((curwin->w_topline >= curbuf->b_ml.ml_line_count - p_so)
2375 && curwin->w_botline > curbuf->b_ml.ml_line_count)
2376 : (curwin->w_topline == 1
2377 #ifdef FEAT_DIFF
2378 && curwin->w_topfill ==
2379 diff_check_fill(curwin, curwin->w_topline)
2380 #endif
2383 beep_flush();
2384 retval = FAIL;
2385 break;
2388 #ifdef FEAT_DIFF
2389 loff.fill = 0;
2390 #endif
2391 if (dir == FORWARD)
2393 if (firstwin == lastwin && p_window > 0 && p_window < Rows - 1)
2395 /* Vi compatible scrolling */
2396 if (p_window <= 2)
2397 ++curwin->w_topline;
2398 else
2399 curwin->w_topline += p_window - 2;
2400 if (curwin->w_topline > curbuf->b_ml.ml_line_count)
2401 curwin->w_topline = curbuf->b_ml.ml_line_count;
2402 curwin->w_cursor.lnum = curwin->w_topline;
2404 else if (curwin->w_botline > curbuf->b_ml.ml_line_count)
2406 /* at end of file */
2407 curwin->w_topline = curbuf->b_ml.ml_line_count;
2408 #ifdef FEAT_DIFF
2409 curwin->w_topfill = 0;
2410 #endif
2411 curwin->w_valid &= ~(VALID_WROW|VALID_CROW);
2413 else
2415 /* For the overlap, start with the line just below the window
2416 * and go upwards. */
2417 loff.lnum = curwin->w_botline;
2418 #ifdef FEAT_DIFF
2419 loff.fill = diff_check_fill(curwin, loff.lnum)
2420 - curwin->w_filler_rows;
2421 #endif
2422 get_scroll_overlap(&loff, -1);
2423 curwin->w_topline = loff.lnum;
2424 #ifdef FEAT_DIFF
2425 curwin->w_topfill = loff.fill;
2426 check_topfill(curwin, FALSE);
2427 #endif
2428 curwin->w_cursor.lnum = curwin->w_topline;
2429 curwin->w_valid &= ~(VALID_WCOL|VALID_CHEIGHT|VALID_WROW|
2430 VALID_CROW|VALID_BOTLINE|VALID_BOTLINE_AP);
2433 else /* dir == BACKWARDS */
2435 #ifdef FEAT_DIFF
2436 if (curwin->w_topline == 1)
2438 /* Include max number of filler lines */
2439 max_topfill();
2440 continue;
2442 #endif
2443 if (firstwin == lastwin && p_window > 0 && p_window < Rows - 1)
2445 /* Vi compatible scrolling (sort of) */
2446 if (p_window <= 2)
2447 --curwin->w_topline;
2448 else
2449 curwin->w_topline -= p_window - 2;
2450 if (curwin->w_topline < 1)
2451 curwin->w_topline = 1;
2452 curwin->w_cursor.lnum = curwin->w_topline + p_window - 1;
2453 if (curwin->w_cursor.lnum > curbuf->b_ml.ml_line_count)
2454 curwin->w_cursor.lnum = curbuf->b_ml.ml_line_count;
2455 continue;
2458 /* Find the line at the top of the window that is going to be the
2459 * line at the bottom of the window. Make sure this results in
2460 * the same line as before doing CTRL-F. */
2461 loff.lnum = curwin->w_topline - 1;
2462 #ifdef FEAT_DIFF
2463 loff.fill = diff_check_fill(curwin, loff.lnum + 1)
2464 - curwin->w_topfill;
2465 #endif
2466 get_scroll_overlap(&loff, 1);
2468 if (loff.lnum >= curbuf->b_ml.ml_line_count)
2470 loff.lnum = curbuf->b_ml.ml_line_count;
2471 #ifdef FEAT_DIFF
2472 loff.fill = 0;
2474 else
2476 botline_topline(&loff);
2477 #endif
2479 curwin->w_cursor.lnum = loff.lnum;
2481 /* Find the line just above the new topline to get the right line
2482 * at the bottom of the window. */
2483 n = 0;
2484 while (n <= curwin->w_height && loff.lnum >= 1)
2486 topline_back(&loff);
2487 if (loff.height == MAXCOL)
2488 n = MAXCOL;
2489 else
2490 n += loff.height;
2492 if (loff.lnum < 1) /* at begin of file */
2494 curwin->w_topline = 1;
2495 #ifdef FEAT_DIFF
2496 max_topfill();
2497 #endif
2498 curwin->w_valid &= ~(VALID_WROW|VALID_CROW|VALID_BOTLINE);
2500 else
2502 /* Go two lines forward again. */
2503 #ifdef FEAT_DIFF
2504 topline_botline(&loff);
2505 #endif
2506 botline_forw(&loff);
2507 botline_forw(&loff);
2508 #ifdef FEAT_DIFF
2509 botline_topline(&loff);
2510 #endif
2511 #ifdef FEAT_FOLDING
2512 /* We're at the wrong end of a fold now. */
2513 (void)hasFolding(loff.lnum, &loff.lnum, NULL);
2514 #endif
2516 /* Always scroll at least one line. Avoid getting stuck on
2517 * very long lines. */
2518 if (loff.lnum >= curwin->w_topline
2519 #ifdef FEAT_DIFF
2520 && (loff.lnum > curwin->w_topline
2521 || loff.fill >= curwin->w_topfill)
2522 #endif
2525 #ifdef FEAT_DIFF
2526 /* First try using the maximum number of filler lines. If
2527 * that's not enough, backup one line. */
2528 loff.fill = curwin->w_topfill;
2529 if (curwin->w_topfill < diff_check_fill(curwin,
2530 curwin->w_topline))
2531 max_topfill();
2532 if (curwin->w_topfill == loff.fill)
2533 #endif
2535 --curwin->w_topline;
2536 #ifdef FEAT_DIFF
2537 curwin->w_topfill = 0;
2538 #endif
2540 comp_botline(curwin);
2541 curwin->w_cursor.lnum = curwin->w_botline - 1;
2542 curwin->w_valid &= ~(VALID_WCOL|VALID_CHEIGHT|
2543 VALID_WROW|VALID_CROW);
2545 else
2547 curwin->w_topline = loff.lnum;
2548 #ifdef FEAT_DIFF
2549 curwin->w_topfill = loff.fill;
2550 check_topfill(curwin, FALSE);
2551 #endif
2552 curwin->w_valid &= ~(VALID_WROW|VALID_CROW|VALID_BOTLINE);
2557 #ifdef FEAT_FOLDING
2558 foldAdjustCursor();
2559 #endif
2560 cursor_correct();
2561 if (retval == OK)
2562 beginline(BL_SOL | BL_FIX);
2563 curwin->w_valid &= ~(VALID_WCOL|VALID_WROW|VALID_VIRTCOL);
2566 * Avoid the screen jumping up and down when 'scrolloff' is non-zero.
2567 * But make sure we scroll at least one line (happens with mix of long
2568 * wrapping lines and non-wrapping line).
2570 if (retval == OK && dir == FORWARD && check_top_offset())
2572 scroll_cursor_top(1, FALSE);
2573 if (curwin->w_topline <= old_topline
2574 && old_topline < curbuf->b_ml.ml_line_count)
2576 curwin->w_topline = old_topline + 1;
2577 #ifdef FEAT_FOLDING
2578 (void)hasFolding(curwin->w_topline, &curwin->w_topline, NULL);
2579 #endif
2583 redraw_later(VALID);
2584 return retval;
2588 * Decide how much overlap to use for page-up or page-down scrolling.
2589 * This is symmetric, so that doing both keeps the same lines displayed.
2590 * Three lines are examined:
2592 * before CTRL-F after CTRL-F / before CTRL-B
2593 * etc. l1
2594 * l1 last but one line ------------
2595 * l2 last text line l2 top text line
2596 * ------------- l3 second text line
2597 * l3 etc.
2599 static void
2600 get_scroll_overlap(lp, dir)
2601 lineoff_T *lp;
2602 int dir;
2604 int h1, h2, h3, h4;
2605 int min_height = curwin->w_height - 2;
2606 lineoff_T loff0, loff1, loff2;
2608 #ifdef FEAT_DIFF
2609 if (lp->fill > 0)
2610 lp->height = 1;
2611 else
2612 lp->height = plines_nofill(lp->lnum);
2613 #else
2614 lp->height = plines(lp->lnum);
2615 #endif
2616 h1 = lp->height;
2617 if (h1 > min_height)
2618 return; /* no overlap */
2620 loff0 = *lp;
2621 if (dir > 0)
2622 botline_forw(lp);
2623 else
2624 topline_back(lp);
2625 h2 = lp->height;
2626 if (h2 + h1 > min_height)
2628 *lp = loff0; /* no overlap */
2629 return;
2632 loff1 = *lp;
2633 if (dir > 0)
2634 botline_forw(lp);
2635 else
2636 topline_back(lp);
2637 h3 = lp->height;
2638 if (h3 + h2 > min_height)
2640 *lp = loff0; /* no overlap */
2641 return;
2644 loff2 = *lp;
2645 if (dir > 0)
2646 botline_forw(lp);
2647 else
2648 topline_back(lp);
2649 h4 = lp->height;
2650 if (h4 + h3 + h2 > min_height || h3 + h2 + h1 > min_height)
2651 *lp = loff1; /* 1 line overlap */
2652 else
2653 *lp = loff2; /* 2 lines overlap */
2654 return;
2657 /* #define KEEP_SCREEN_LINE */
2659 * Scroll 'scroll' lines up or down.
2661 void
2662 halfpage(flag, Prenum)
2663 int flag;
2664 linenr_T Prenum;
2666 long scrolled = 0;
2667 int i;
2668 int n;
2669 int room;
2671 if (Prenum)
2672 curwin->w_p_scr = (Prenum > curwin->w_height) ?
2673 curwin->w_height : Prenum;
2674 n = (curwin->w_p_scr <= curwin->w_height) ?
2675 curwin->w_p_scr : curwin->w_height;
2677 validate_botline();
2678 room = curwin->w_empty_rows;
2679 #ifdef FEAT_DIFF
2680 room += curwin->w_filler_rows;
2681 #endif
2682 if (flag)
2685 * scroll the text up
2687 while (n > 0 && curwin->w_botline <= curbuf->b_ml.ml_line_count)
2689 #ifdef FEAT_DIFF
2690 if (curwin->w_topfill > 0)
2692 i = 1;
2693 if (--n < 0 && scrolled > 0)
2694 break;
2695 --curwin->w_topfill;
2697 else
2698 #endif
2700 #ifdef FEAT_DIFF
2701 i = plines_nofill(curwin->w_topline);
2702 #else
2703 i = plines(curwin->w_topline);
2704 #endif
2705 n -= i;
2706 if (n < 0 && scrolled > 0)
2707 break;
2708 #ifdef FEAT_FOLDING
2709 (void)hasFolding(curwin->w_topline, NULL, &curwin->w_topline);
2710 #endif
2711 ++curwin->w_topline;
2712 #ifdef FEAT_DIFF
2713 curwin->w_topfill = diff_check_fill(curwin, curwin->w_topline);
2714 #endif
2716 #ifndef KEEP_SCREEN_LINE
2717 if (curwin->w_cursor.lnum < curbuf->b_ml.ml_line_count)
2719 ++curwin->w_cursor.lnum;
2720 curwin->w_valid &=
2721 ~(VALID_VIRTCOL|VALID_CHEIGHT|VALID_WCOL);
2723 #endif
2725 curwin->w_valid &= ~(VALID_CROW|VALID_WROW);
2726 scrolled += i;
2729 * Correct w_botline for changed w_topline.
2730 * Won't work when there are filler lines.
2732 #ifdef FEAT_DIFF
2733 if (curwin->w_p_diff)
2734 curwin->w_valid &= ~(VALID_BOTLINE|VALID_BOTLINE_AP);
2735 else
2736 #endif
2738 room += i;
2741 i = plines(curwin->w_botline);
2742 if (i > room)
2743 break;
2744 #ifdef FEAT_FOLDING
2745 (void)hasFolding(curwin->w_botline, NULL,
2746 &curwin->w_botline);
2747 #endif
2748 ++curwin->w_botline;
2749 room -= i;
2750 } while (curwin->w_botline <= curbuf->b_ml.ml_line_count);
2754 #ifndef KEEP_SCREEN_LINE
2756 * When hit bottom of the file: move cursor down.
2758 if (n > 0)
2760 # ifdef FEAT_FOLDING
2761 if (hasAnyFolding(curwin))
2763 while (--n >= 0
2764 && curwin->w_cursor.lnum < curbuf->b_ml.ml_line_count)
2766 (void)hasFolding(curwin->w_cursor.lnum, NULL,
2767 &curwin->w_cursor.lnum);
2768 ++curwin->w_cursor.lnum;
2771 else
2772 # endif
2773 curwin->w_cursor.lnum += n;
2774 check_cursor_lnum();
2776 #else
2777 /* try to put the cursor in the same screen line */
2778 while ((curwin->w_cursor.lnum < curwin->w_topline || scrolled > 0)
2779 && curwin->w_cursor.lnum < curwin->w_botline - 1)
2781 scrolled -= plines(curwin->w_cursor.lnum);
2782 if (scrolled < 0 && curwin->w_cursor.lnum >= curwin->w_topline)
2783 break;
2784 # ifdef FEAT_FOLDING
2785 (void)hasFolding(curwin->w_cursor.lnum, NULL,
2786 &curwin->w_cursor.lnum);
2787 # endif
2788 ++curwin->w_cursor.lnum;
2790 #endif
2792 else
2795 * scroll the text down
2797 while (n > 0 && curwin->w_topline > 1)
2799 #ifdef FEAT_DIFF
2800 if (curwin->w_topfill < diff_check_fill(curwin, curwin->w_topline))
2802 i = 1;
2803 if (--n < 0 && scrolled > 0)
2804 break;
2805 ++curwin->w_topfill;
2807 else
2808 #endif
2810 #ifdef FEAT_DIFF
2811 i = plines_nofill(curwin->w_topline - 1);
2812 #else
2813 i = plines(curwin->w_topline - 1);
2814 #endif
2815 n -= i;
2816 if (n < 0 && scrolled > 0)
2817 break;
2818 --curwin->w_topline;
2819 #ifdef FEAT_FOLDING
2820 (void)hasFolding(curwin->w_topline, &curwin->w_topline, NULL);
2821 #endif
2822 #ifdef FEAT_DIFF
2823 curwin->w_topfill = 0;
2824 #endif
2826 curwin->w_valid &= ~(VALID_CROW|VALID_WROW|
2827 VALID_BOTLINE|VALID_BOTLINE_AP);
2828 scrolled += i;
2829 #ifndef KEEP_SCREEN_LINE
2830 if (curwin->w_cursor.lnum > 1)
2832 --curwin->w_cursor.lnum;
2833 curwin->w_valid &= ~(VALID_VIRTCOL|VALID_CHEIGHT|VALID_WCOL);
2835 #endif
2837 #ifndef KEEP_SCREEN_LINE
2839 * When hit top of the file: move cursor up.
2841 if (n > 0)
2843 if (curwin->w_cursor.lnum <= (linenr_T)n)
2844 curwin->w_cursor.lnum = 1;
2845 else
2846 # ifdef FEAT_FOLDING
2847 if (hasAnyFolding(curwin))
2849 while (--n >= 0 && curwin->w_cursor.lnum > 1)
2851 --curwin->w_cursor.lnum;
2852 (void)hasFolding(curwin->w_cursor.lnum,
2853 &curwin->w_cursor.lnum, NULL);
2856 else
2857 # endif
2858 curwin->w_cursor.lnum -= n;
2860 #else
2861 /* try to put the cursor in the same screen line */
2862 scrolled += n; /* move cursor when topline is 1 */
2863 while (curwin->w_cursor.lnum > curwin->w_topline
2864 && (scrolled > 0 || curwin->w_cursor.lnum >= curwin->w_botline))
2866 scrolled -= plines(curwin->w_cursor.lnum - 1);
2867 if (scrolled < 0 && curwin->w_cursor.lnum < curwin->w_botline)
2868 break;
2869 --curwin->w_cursor.lnum;
2870 # ifdef FEAT_FOLDING
2871 foldAdjustCursor();
2872 # endif
2874 #endif
2876 # ifdef FEAT_FOLDING
2877 /* Move cursor to first line of closed fold. */
2878 foldAdjustCursor();
2879 # endif
2880 #ifdef FEAT_DIFF
2881 check_topfill(curwin, !flag);
2882 #endif
2883 cursor_correct();
2884 beginline(BL_SOL | BL_FIX);
2885 redraw_later(VALID);