static struct glyph_row *get_overlay_arrow_glyph_row P_ ((struct window *));
static void extend_face_to_end_of_line P_ ((struct it *));
static int append_space P_ ((struct it *, int));
-static void make_cursor_line_fully_visible P_ ((struct window *));
+static int make_cursor_line_fully_visible P_ ((struct window *));
static int try_scrolling P_ ((Lisp_Object, int, int, int, int));
static int try_cursor_movement P_ ((Lisp_Object, struct text_pos, int *));
static int trailing_whitespace_p P_ ((int));
/* Modify the desired matrix of window W and W->vscroll so that the
- line containing the cursor is fully visible. */
+ line containing the cursor is fully visible. If this requires
+ larger matrices than are allocated, set fonts_changed_p and return
+ 0. */
-static void
+static int
make_cursor_line_fully_visible (w)
struct window *w;
{
/* It's not always possible to find the cursor, e.g, when a window
is full of overlay strings. Don't do anything in that case. */
if (w->cursor.vpos < 0)
- return;
+ return 1;
matrix = w->desired_matrix;
row = MATRIX_ROW (matrix, w->cursor.vpos);
/* If the cursor row is not partially visible, there's nothing
to do. */
if (!MATRIX_ROW_PARTIALLY_VISIBLE_P (row))
- return;
+ return 1;
/* If the row the cursor is in is taller than the window's height,
it's not clear what to do, so do nothing. */
window_height = window_box_height (w);
if (row->height >= window_height)
- return;
+ return 1;
if (MATRIX_ROW_PARTIALLY_VISIBLE_AT_TOP_P (w, row))
{
the correct y-position. */
if (w == XWINDOW (selected_window))
this_line_y = w->cursor.y;
+
+ /* If vscrolling requires a larger glyph matrix, arrange for a fresh
+ redisplay with larger matrices. */
+ if (matrix->nrows < required_matrix_height (w))
+ {
+ fonts_changed_p = 1;
+ return 0;
+ }
+
+ return 1;
}
-1 if new fonts have been loaded so that we must interrupt
redisplay, adjust glyph matrices, and try again. */
+enum
+{
+ SCROLLING_SUCCESS,
+ SCROLLING_FAILED,
+ SCROLLING_NEED_LARGER_MATRICES
+};
+
static int
try_scrolling (window, just_this_one_p, scroll_conservatively,
scroll_step, temp_scroll_step)
dy = 1 + it.current_y - y0;
if (dy > scroll_max)
- return 0;
+ return SCROLLING_FAILED;
/* Move the window start down. If scrolling conservatively,
move it just enough down to make point visible. If
}
if (amount_to_scroll <= 0)
- return 0;
+ return SCROLLING_FAILED;
move_it_vertically (&it, amount_to_scroll);
startp = it.current.pos;
MOVE_TO_POS | MOVE_TO_X | MOVE_TO_Y);
dy = it.current_y - y0;
if (dy > scroll_max)
- return 0;
+ return SCROLLING_FAILED;
/* Compute new window start. */
start_display (&it, w, startp);
}
if (amount_to_scroll <= 0)
- return 0;
+ return SCROLLING_FAILED;
move_it_vertically (&it, - amount_to_scroll);
startp = it.current.pos;
/* Display the window. Give up if new fonts are loaded, or if point
doesn't appear. */
if (!try_window (window, startp))
- rc = -1;
+ rc = SCROLLING_NEED_LARGER_MATRICES;
else if (w->cursor.vpos < 0)
{
clear_glyph_matrix (w->desired_matrix);
- rc = 0;
+ rc = SCROLLING_FAILED;
}
else
{
w->base_line_number = Qnil;
/* If cursor ends up on a partially visible line, shift display
- lines up or down. */
- make_cursor_line_fully_visible (w);
- rc = 1;
+ lines up or down. If that fails because we need larger
+ matrices, give up. */
+ if (!make_cursor_line_fully_visible (w))
+ rc = SCROLLING_NEED_LARGER_MATRICES;
+ else
+ rc = SCROLLING_SUCCESS;
}
return rc;
/* Try cursor movement in case text has not changes in window WINDOW,
with window start STARTP. Value is
- 1 if successful
-
- 0 if this method cannot be used
+ CURSOR_MOVEMENT_SUCCESS if successful
- -1 if we know we have to scroll the display. *SCROLL_STEP is
- set to 1, under certain circumstances, if we want to scroll as
- if scroll-step were set to 1. See the code. */
+ CURSOR_MOVEMENT_CANNOT_BE_USED if this method cannot be used
+
+ CURSOR_MOVEMENT_MUST_SCROLL if we know we have to scroll the
+ display. *SCROLL_STEP is set to 1, under certain circumstances, if
+ we want to scroll as if scroll-step were set to 1. See the code.
+
+ CURSOR_MOVEMENT_NEED_LARGER_MATRICES if we need larger matrices, in
+ which case we have to abort this redisplay, and adjust matrices
+ first. */
+
+enum
+{
+ CURSOR_MOVEMENT_SUCCESS,
+ CURSOR_MOVEMENT_CANNOT_BE_USED,
+ CURSOR_MOVEMENT_MUST_SCROLL,
+ CURSOR_MOVEMENT_NEED_LARGER_MATRICES
+};
static int
try_cursor_movement (window, startp, scroll_step)
{
struct window *w = XWINDOW (window);
struct frame *f = XFRAME (w->frame);
- int rc = 0;
+ int rc = CURSOR_MOVEMENT_CANNOT_BE_USED;
/* Handle case where text has not changed, only point, and it has
not moved off the frame. */
not paused redisplay. Give up if that row is not valid. */
if (w->last_cursor.vpos < 0
|| w->last_cursor.vpos >= w->current_matrix->nrows)
- rc = -1;
+ rc = CURSOR_MOVEMENT_MUST_SCROLL;
else
{
row = MATRIX_ROW (w->current_matrix, w->last_cursor.vpos);
if (row->mode_line_p)
++row;
if (!row->enabled_p)
- rc = -1;
+ rc = CURSOR_MOVEMENT_MUST_SCROLL;
}
- if (rc == 0)
+ if (rc == CURSOR_MOVEMENT_CANNOT_BE_USED)
{
int scroll_p = 0;
int last_y = window_text_bottom_y (w) - this_scroll_margin;
|| PT > MATRIX_ROW_END_CHARPOS (row))
{
/* if PT is not in the glyph row, give up. */
- rc = -1;
+ rc = CURSOR_MOVEMENT_MUST_SCROLL;
}
else if (MATRIX_ROW_PARTIALLY_VISIBLE_P (row))
{
if (PT == MATRIX_ROW_END_CHARPOS (row)
&& !row->ends_at_zv_p
&& !MATRIX_ROW_ENDS_IN_MIDDLE_OF_CHAR_P (row))
- rc = -1;
+ rc = CURSOR_MOVEMENT_MUST_SCROLL;
else if (row->height > window_box_height (w))
{
/* If we end up in a partially visible line, let's
than the window, in which case we can't do much
about it. */
*scroll_step = 1;
- rc = -1;
+ rc = CURSOR_MOVEMENT_MUST_SCROLL;
}
else
{
set_cursor_from_row (w, row, w->current_matrix, 0, 0, 0, 0);
try_window (window, startp);
- make_cursor_line_fully_visible (w);
- rc = 1;
+ if (!make_cursor_line_fully_visible (w))
+ rc = CURSOR_MOVEMENT_NEED_LARGER_MATRICES;
+ else
+ rc = CURSOR_MOVEMENT_SUCCESS;
}
}
else if (scroll_p)
- rc = -1;
+ rc = CURSOR_MOVEMENT_MUST_SCROLL;
else
{
set_cursor_from_row (w, row, w->current_matrix, 0, 0, 0, 0);
- rc = 1;
+ rc = CURSOR_MOVEMENT_SUCCESS;
}
}
}
{
clear_glyph_matrix (w->desired_matrix);
if (!try_window (window, startp))
- goto finish_scroll_bars;
+ goto need_larger_matrices;
}
}
- make_cursor_line_fully_visible (w);
+ if (!make_cursor_line_fully_visible (w))
+ goto need_larger_matrices;
#if GLYPH_DEBUG
debug_method_add (w, "forced window start");
#endif
not moved off the frame. */
if (current_matrix_up_to_date_p
&& (rc = try_cursor_movement (window, startp, &temp_scroll_step),
- rc != 0))
+ rc != CURSOR_MOVEMENT_CANNOT_BE_USED))
{
- if (rc == -1)
- goto try_to_scroll;
- else
- goto done;
+ switch (rc)
+ {
+ case CURSOR_MOVEMENT_SUCCESS:
+ goto done;
+
+ case CURSOR_MOVEMENT_NEED_LARGER_MATRICES:
+ goto need_larger_matrices;
+
+ case CURSOR_MOVEMENT_MUST_SCROLL:
+ goto try_to_scroll;
+
+ default:
+ abort ();
+ }
}
/* If current starting point was originally the beginning of a line
but no longer is, find a new starting point. */
#endif
if (fonts_changed_p)
- goto finish_scroll_bars;
+ goto need_larger_matrices;
if (tem > 0)
goto done;
}
if (fonts_changed_p)
- goto finish_scroll_bars;
+ goto need_larger_matrices;
if (w->cursor.vpos >= 0)
{
/* Forget any recorded base line for line number display. */
w->base_line_number = Qnil;
- make_cursor_line_fully_visible (w);
+ if (!make_cursor_line_fully_visible (w))
+ goto need_larger_matrices;
goto done;
}
else
scroll_conservatively,
scroll_step,
temp_scroll_step);
- if (rc > 0)
- goto done;
- else if (rc < 0)
- goto finish_scroll_bars;
+ switch (rc)
+ {
+ case SCROLLING_SUCCESS:
+ goto done;
+
+ case SCROLLING_NEED_LARGER_MATRICES:
+ goto need_larger_matrices;
+
+ case SCROLLING_FAILED:
+ break;
+
+ default:
+ abort ();
+ }
}
/* Finally, just choose place to start which centers point */
have to start a new redisplay since we need to re-adjust glyph
matrices. */
if (fonts_changed_p)
- goto finish_scroll_bars;
+ goto need_larger_matrices;
/* If cursor did not appear assume that the middle of the window is
in the first line of the window. Do it again with the next line.
set_cursor_from_row (w, row, w->current_matrix, 0, 0, 0, 0);
}
- make_cursor_line_fully_visible (w);
+ if (!make_cursor_line_fully_visible (w))
+ goto need_larger_matrices;
done:
}
if (fonts_changed_p)
- goto finish_scroll_bars;
+ goto need_larger_matrices;
}
if (!line_number_displayed
#endif
}
+ need_larger_matrices:
+ ;
finish_scroll_bars:
if (FRAME_HAS_VERTICAL_SCROLL_BARS (f))
projects / emacs.git / commitdiff