/* Calculate what line insertion or deletion to do, and do it,
- Copyright (C) 1985, 1986, 1990, 1993 Free Software Foundation, Inc.
+ Copyright (C) 1985, 1986, 1990, 1993, 1994 Free Software Foundation, Inc.
This file is part of GNU Emacs.
You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING. If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
#include <config.h>
+#include <stdio.h>
+#include <string.h>
#include "termchar.h"
#include "lisp.h"
#include "dispextern.h"
+#include "keyboard.h"
#include "frame.h"
-
-extern struct display_line **ophys_lines;
-
-#define max(a, b) ((a) > (b) ? (a) : (b))
-#define min(a, b) ((a) < (b) ? (a) : (b))
+#include "window.h"
/* All costs measured in characters.
So no cost can exceed the area of a frame, measured in characters.
- Let's hope this is never more than 15000 characters. */
+ Let's hope this is never more than 1000000 characters. */
-#define INFINITY 15000
+#define INFINITY 1000000
struct matrix_elt
{
/* Cost of outputting through this line
if no insert/delete is done just above it. */
- short writecost;
+ int writecost;
/* Cost of outputting through this line
if an insert is done just above it. */
- short insertcost;
+ int insertcost;
/* Cost of outputting through this line
if a delete is done just above it. */
- short deletecost;
+ int deletecost;
/* Number of inserts so far in this run of inserts,
for the cost in insertcost. */
- char insertcount;
+ unsigned char insertcount;
/* Number of deletes so far in this run of deletes,
for the cost in deletecost. */
- char deletecount;
+ unsigned char deletecount;
+ /* Number of writes so far since the last insert
+ or delete for the cost in writecost. */
+ unsigned char writecount;
};
+static void do_direct_scrolling P_ ((struct glyph_matrix *,
+ struct matrix_elt *,
+ int, int));
+static void do_scrolling P_ ((struct glyph_matrix *,
+ struct matrix_elt *,
+ int, int));
+
\f
-/* Determine, in matrix[i,j], the cost of updating the first j old lines
- into the first i new lines.
+/* Determine, in matrix[i,j], the cost of updating the first j old
+ lines into the first i new lines using the general scrolling method.
This involves using insert or delete somewhere if i != j.
For each matrix elements, three kinds of costs are recorded:
the smallest cost that ends with an insert, the smallest
int lines_moved = window_size + (scroll_region_ok ? 0 : lines_below);
/* first_insert_cost[I] is the cost of doing the first insert-line
- at the I'th line of the lines we are considering,
+ at the i'th line of the lines we are considering,
where I is origin 1 (as it is below). */
int *first_insert_cost
= &FRAME_INSERT_COST (frame)[frame_height - 1 - lines_moved];
else
{
cost = p1->writecost + first_insert_cost[i];
- if (p1->insertcount > i)
+ if ((int) p1->insertcount > i)
abort ();
cost1 = p1->insertcost + next_insert_cost[i - p1->insertcount];
}
p->insertcost = min (cost, cost1) + draw_cost[i] + extra_cost;
p->insertcount = (cost < cost1) ? 1 : p1->insertcount + 1;
- if (p->insertcount > i)
+ if ((int) p->insertcount > i)
abort ();
/* Calculate the cost if we do a delete line after
p->deletecount = (cost < cost1) ? 1 : p1->deletecount + 1;
}
}
+
+
\f
-/* Perform insert-lines and delete-lines operations on FRAME
- according to the costs in MATRIX.
- Update the frame's current_glyphs info to record what was done.
+/* Perform insert-lines and delete-lines operations on CURRENT_MATRIX
+ according to the costs in MATRIX, using the general scrolling
+ method that is used if the terminal does not support the setting of
+ scroll windows (scroll_region_ok == 0).
WINDOW_SIZE is the number of lines being considered for scrolling
- and UNCHANGED_AT_TOP is the vpos of the first line being considered.
- These two arguments can specify any contiguous range of lines.
+ and UNCHANGED_AT_TOP is the vpos of the first line being
+ considered. These two arguments can specify any contiguous range
+ of lines. */
- We also shuffle the charstarts vectors for the lines
- along with the glyphs; but the results are not quite right,
- since we cannot offset them for changes in amount of text
- in this line or that line. Luckily it doesn't matter,
- since update_frame and update_line will copy in the proper
- new charstarts vectors from the frame's desired_glyphs. */
-
static void
-do_scrolling (frame, matrix, window_size, unchanged_at_top)
- FRAME_PTR frame;
+do_scrolling (current_matrix, matrix, window_size, unchanged_at_top)
+ struct glyph_matrix *current_matrix;
struct matrix_elt *matrix;
int window_size;
int unchanged_at_top;
{
- register struct matrix_elt *p;
- register int i, j;
- register struct frame_glyphs *current_frame;
- /* temp_frame->enable[i] means line i has been moved to current_frame. */
- register struct frame_glyphs *temp_frame;
- struct queue { int count, pos; } *queue;
- int offset = unchanged_at_top;
- int qi = 0;
- int window = 0;
- register int tem;
- int next;
-
- queue = (struct queue *) alloca (FRAME_HEIGHT (frame)
- * sizeof (struct queue));
-
- current_frame = FRAME_CURRENT_GLYPHS (frame);
- temp_frame = FRAME_TEMP_GLYPHS (frame);
-
- bcopy (current_frame->glyphs, temp_frame->glyphs,
- current_frame->height * sizeof (GLYPH *));
- bcopy (current_frame->charstarts, temp_frame->charstarts,
- current_frame->height * sizeof (GLYPH *));
- bcopy (current_frame->used, temp_frame->used,
- current_frame->height * sizeof (int));
- bcopy (current_frame->highlight, temp_frame->highlight,
- current_frame->height * sizeof (char));
- bzero (temp_frame->enable, temp_frame->height * sizeof (char));
- bcopy (current_frame->bufp, temp_frame->bufp,
- current_frame->height * sizeof (int));
-
-#ifdef HAVE_X_WINDOWS
- if (FRAME_X_P (frame))
- {
- bcopy (current_frame->top_left_x, temp_frame->top_left_x,
- current_frame->height * sizeof (short));
- bcopy (current_frame->top_left_y, temp_frame->top_left_y,
- current_frame->height * sizeof (short));
- bcopy (current_frame->pix_width, temp_frame->pix_width,
- current_frame->height * sizeof (short));
- bcopy (current_frame->pix_height, temp_frame->pix_height,
- current_frame->height * sizeof (short));
- bcopy (current_frame->max_ascent, temp_frame->max_ascent,
- current_frame->height * sizeof (short));
- }
-#endif
-
+ struct matrix_elt *p;
+ int i, j, k;
+
+ /* Set to 1 if we have set a terminal window with
+ set_terminal_window. */
+ int terminal_window_p = 0;
+
+ /* A queue for line insertions to be done. */
+ struct queue { int count, pos; };
+ struct queue *queue_start
+ = (struct queue *) alloca (current_matrix->nrows * sizeof (struct queue));
+ struct queue *queue = queue_start;
+
+ char *retained_p = (char *) alloca (window_size * sizeof (char));
+ int *copy_from = (int *) alloca (window_size * sizeof (int));
+
+ /* Zero means line is empty. */
+ bzero (retained_p, window_size * sizeof (char));
+ for (k = 0; k < window_size; ++k)
+ copy_from[k] = -1;
+
+#define CHECK_BOUNDS \
+ do \
+ { \
+ int k; \
+ for (k = 0; k < window_size; ++k) \
+ xassert (copy_from[k] == -1 \
+ || (copy_from[k] >= 0 && copy_from[k] < window_size)); \
+ } \
+ while (0);
+
+ /* When j is advanced, this corresponds to deleted lines.
+ When i is advanced, this corresponds to inserted lines. */
i = j = window_size;
-
while (i > 0 || j > 0)
{
p = matrix + i * (window_size + 1) + j;
- tem = p->insertcost;
- if (tem < p->writecost && tem < p->deletecost)
+
+ if (p->insertcost < p->writecost && p->insertcost < p->deletecost)
{
- /* Insert should be done at vpos i-1, plus maybe some before */
- queue[qi].count = p->insertcount;
+ /* Insert should be done at vpos i-1, plus maybe some before.
+ Queue the screen operation to be performed. */
+ queue->count = p->insertcount;
+ queue->pos = i + unchanged_at_top - p->insertcount;
+ ++queue;
+
+ /* By incrementing I, we leave room in the result rows
+ for the empty rows opened up. */
i -= p->insertcount;
- queue[qi++].pos = i + unchanged_at_top;
}
else if (p->deletecost < p->writecost)
{
- /* Old line at vpos j-1, and maybe some before it,
- should be deleted */
+ /* Old line at vpos j-1, and maybe some before it, should be
+ deleted. By decrementing J, we skip some lines in the
+ temp_rows which is equivalent to omitting these lines in
+ the result rows, thus deleting them. */
j -= p->deletecount;
- if (!window)
+
+ /* Set the terminal window, if not done already. */
+ if (! terminal_window_p)
{
set_terminal_window (window_size + unchanged_at_top);
- window = 1;
+ terminal_window_p = 1;
}
+
+ /* Delete lines on the terminal. */
ins_del_lines (j + unchanged_at_top, - p->deletecount);
}
else
{
- /* Best thing done here is no insert or delete */
- /* Old line at vpos j-1 ends up at vpos i-1 */
- current_frame->glyphs[i + offset - 1]
- = temp_frame->glyphs[j + offset - 1];
- current_frame->charstarts[i + offset - 1]
- = temp_frame->charstarts[j + offset - 1];
- current_frame->used[i + offset - 1]
- = temp_frame->used[j + offset - 1];
- current_frame->highlight[i + offset - 1]
- = temp_frame->highlight[j + offset - 1];
-
- temp_frame->enable[j + offset - 1] = 1;
- i--;
- j--;
+ /* Best thing done here is no insert or delete, i.e. a write. */
+ --i, --j;
+ xassert (i >= 0 && i < window_size);
+ xassert (j >= 0 && j < window_size);
+ copy_from[i] = j;
+ retained_p[j] = 1;
+
+#if GLYPH_DEBUG
+ CHECK_BOUNDS;
+#endif
}
}
- if (!window && qi)
+ /* Now do all insertions queued above. */
+ if (queue > queue_start)
{
- set_terminal_window (window_size + unchanged_at_top);
- window = 1;
+ int next = -1;
+
+ /* Set the terminal window if not yet done. */
+ if (!terminal_window_p)
+ {
+ set_terminal_window (window_size + unchanged_at_top);
+ terminal_window_p = 1;
+ }
+
+ do
+ {
+ --queue;
+
+ /* Do the deletion on the terminal. */
+ ins_del_lines (queue->pos, queue->count);
+
+ /* All lines in the range deleted become empty in the glyph
+ matrix. Assign to them glyph rows that are not retained.
+ K is the starting position of the deleted range relative
+ to the window we are working in. */
+ k = queue->pos - unchanged_at_top;
+ for (j = 0; j < queue->count; ++j)
+ {
+ /* Find the next row not retained. */
+ while (retained_p[++next])
+ ;
+
+ /* Record that this row is to be used for the empty
+ glyph row j. */
+ copy_from[k + j] = next;
+ }
+ }
+ while (queue > queue_start);
+
}
- /* Now do all insertions */
+ for (k = 0; k < window_size; ++k)
+ xassert (copy_from[k] >= 0 && copy_from[k] < window_size);
+
+ /* Perform the row swizzling. */
+ mirrored_line_dance (current_matrix, unchanged_at_top, window_size,
+ copy_from, retained_p);
+
+ /* Some sanity checks if GLYPH_DEBUG != 0. */
+ CHECK_MATRIX (current_matrix);
+
+ if (terminal_window_p)
+ set_terminal_window (0);
+}
+
+\f
+/* Determine, in matrix[i,j], the cost of updating the first j
+ old lines into the first i new lines using the direct
+ scrolling method. When the old line and the new line have
+ different hash codes, the calculated cost of updating old
+ line j into new line i includes the cost of outputting new
+ line i, and if i != j, the cost of outputting the old line j
+ is also included, as a penalty for moving the line and then
+ erasing it. In addition, the cost of updating a sequence of
+ lines with constant i - j includes the cost of scrolling the
+ old lines into their new positions, unless i == j. Scrolling
+ is achieved by setting the screen window to avoid affecting
+ other lines below, and inserting or deleting lines at the top
+ of the scrolled region. The cost of scrolling a sequence of
+ lines includes the fixed cost of specifying a scroll region,
+ plus a variable cost which can depend upon the number of lines
+ involved and the distance by which they are scrolled, and an
+ extra cost to discourage long scrolls.
+
+ As reflected in the matrix, an insert or delete does not
+ correspond directly to the insertion or deletion which is
+ used in scrolling lines. An insert means that the value of i
+ has increased without a corresponding increase in the value
+ of j. A delete means that the value of j has increased
+ without a corresponding increase in the value of i. A write
+ means that i and j are both increased by the same amount, and
+ that the old lines will be moved to their new positions.
+
+ An insert following a delete is allowed only if i > j.
+ A delete following an insert is allowed only if i < j.
+ These restrictions ensure that the new lines in an insert
+ will always be blank as an effect of the neighboring writes.
+ Thus the calculated cost of an insert is simply the cost of
+ outputting the new line contents. The direct cost of a
+ delete is zero. Inserts and deletes indirectly affect the
+ total cost through their influence on subsequent writes. */
+
+/* The vectors draw_cost, old_hash, and new_hash have the same
+ meanings here as in calculate_scrolling, and old_draw_cost
+ is the equivalent of draw_cost for the old line contents */
+
+static void
+calculate_direct_scrolling (frame, matrix, window_size, lines_below,
+ draw_cost, old_draw_cost, old_hash, new_hash,
+ free_at_end)
+ FRAME_PTR frame;
+ /* matrix is of size window_size + 1 on each side. */
+ struct matrix_elt *matrix;
+ int window_size;
+ int *draw_cost;
+ int *old_draw_cost;
+ int *old_hash;
+ int *new_hash;
+ int free_at_end;
+{
+ register int i, j;
+ int frame_height = FRAME_HEIGHT (frame);
+ register struct matrix_elt *p, *p1;
+ register int cost, cost1, delta;
+
+ /* first_insert_cost[-I] is the cost of doing the first insert-line
+ at a position I lines above the bottom line in the scroll window. */
+ int *first_insert_cost
+ = &FRAME_INSERT_COST (frame)[frame_height - 1];
+ int *first_delete_cost
+ = &FRAME_DELETE_COST (frame)[frame_height - 1];
+ int *next_insert_cost
+ = &FRAME_INSERTN_COST (frame)[frame_height - 1];
+ int *next_delete_cost
+ = &FRAME_DELETEN_COST (frame)[frame_height - 1];
+
+ int scroll_overhead;
+
+ /* Discourage long scrolls on fast lines.
+ Don't scroll nearly a full frame height unless it saves
+ at least 1/4 second. */
+ int extra_cost = baud_rate / (10 * 4 * FRAME_HEIGHT (frame));
+
+ if (baud_rate <= 0)
+ extra_cost = 1;
+
+ /* Overhead of setting the scroll window, plus the extra cost
+ cost of scrolling by a distance of one. The extra cost is
+ added once for consistency with the cost vectors */
+ scroll_overhead = scroll_region_cost + extra_cost;
+
+ /* initialize the top left corner of the matrix */
+ matrix->writecost = 0;
+ matrix->insertcost = INFINITY;
+ matrix->deletecost = INFINITY;
+ matrix->writecount = 0;
+ matrix->insertcount = 0;
+ matrix->deletecount = 0;
+
+ /* initialize the left edge of the matrix */
+ cost = 0;
+ for (i = 1; i <= window_size; i++)
+ {
+ p = matrix + i * (window_size + 1);
+ cost += draw_cost[i];
+ p->insertcost = cost;
+ p->writecost = INFINITY;
+ p->deletecost = INFINITY;
+ p->insertcount = i;
+ p->writecount = 0;
+ p->deletecount = 0;
+ }
+
+ /* initialize the top edge of the matrix */
+ for (j = 1; j <= window_size; j++)
+ {
+ matrix[j].deletecost = 0;
+ matrix[j].writecost = INFINITY;
+ matrix[j].insertcost = INFINITY;
+ matrix[j].deletecount = j;
+ matrix[j].writecount = 0;
+ matrix[j].insertcount = 0;
+ }
+
+ /* `i' represents the vpos among new frame contents.
+ `j' represents the vpos among the old frame contents. */
+ p = matrix + window_size + 2; /* matrix [1, 1] */
+
+ for (i = 1; i <= window_size; i++, p++)
+ for (j = 1; j <= window_size; j++, p++)
+ {
+ /* p contains the address of matrix [i, j] */
+
+ /* First calculate the cost assuming we do
+ not insert or delete above this line.
+ That is, if we update through line i-1
+ based on old lines through j-1,
+ and then just change old line j to new line i.
+
+ Depending on which choice gives the lower cost,
+ this usually involves either scrolling a single line
+ or extending a sequence of scrolled lines, but
+ when i == j, no scrolling is required. */
+ p1 = p - window_size - 2; /* matrix [i-1, j-1] */
+ cost = p1->insertcost;
+ if (cost > p1->deletecost)
+ cost = p1->deletecost;
+ cost1 = p1->writecost;
+ if (i == j)
+ {
+ if (cost > cost1)
+ {
+ cost = cost1;
+ p->writecount = p1->writecount + 1;
+ }
+ else
+ p->writecount = 1;
+ if (old_hash[j] != new_hash[i])
+ {
+ cost += draw_cost[i];
+ }
+ }
+ else
+ {
+ if (i > j)
+ {
+ delta = i - j;
+
+ /* The cost added here for scrolling the first line by
+ a distance N includes the overhead of setting the
+ scroll window, the cost of inserting N lines at a
+ position N lines above the bottom line of the window,
+ and an extra cost which is proportional to N. */
+ cost += scroll_overhead + first_insert_cost[-delta] +
+ (delta-1) * (next_insert_cost[-delta] + extra_cost);
+
+ /* In the most general case, the insertion overhead and
+ the multiply factor can grow linearly as the distance
+ from the bottom of the window increases. The incremental
+ cost of scrolling an additional line depends upon the
+ rate of change of these two parameters. Each of these
+ growth rates can be determined by a simple difference.
+ To reduce the cumulative effects of rounding error, we
+ vary the position at which the difference is computed. */
+ cost1 += first_insert_cost[-j] - first_insert_cost[1-j] +
+ (delta-1) * (next_insert_cost[-j] - next_insert_cost[1-j]);
+ }
+ else
+ {
+ delta = j - i;
+ cost += scroll_overhead + first_delete_cost[-delta] +
+ (delta-1) * (next_delete_cost[-delta] + extra_cost);
+ cost1 += first_delete_cost[-i] - first_delete_cost[1-i] +
+ (delta-1) * ( next_delete_cost[-i] - next_delete_cost[1-i]);
+ }
+ if (cost1 < cost)
+ {
+ cost = cost1;
+ p->writecount = p1->writecount + 1;
+ }
+ else
+ p->writecount = 1;
+ if (old_hash[j] != new_hash[i])
+ {
+ cost += draw_cost[i] + old_draw_cost[j];
+ }
+ }
+ p->writecost = cost;
+
+ /* Calculate the cost if we do an insert-line
+ before outputting this line.
+ That is, we update through line i-1
+ based on old lines through j,
+ do an insert-line on line i,
+ and then output line i from scratch,
+ leaving old lines starting from j for reuse below. */
+ p1 = p - window_size - 1; /* matrix [i-1, j] */
+ cost = p1->writecost;
+ /* If i > j, an insert is allowed after a delete. */
+ if (i > j && p1->deletecost < cost)
+ cost = p1->deletecost;
+ if (p1->insertcost <= cost)
+ {
+ cost = p1->insertcost;
+ p->insertcount = p1->insertcount + 1;
+ }
+ else
+ p->insertcount = 1;
+ cost += draw_cost[i];
+ p->insertcost = cost;
+
+ /* Calculate the cost if we do a delete line after
+ outputting this line.
+ That is, we update through line i
+ based on old lines through j-1,
+ and throw away old line j. */
+ p1 = p - 1; /* matrix [i, j-1] */
+ cost = p1->writecost;
+ /* If i < j, a delete is allowed after an insert. */
+ if (i < j && p1->insertcost < cost)
+ cost = p1->insertcost;
+ cost1 = p1->deletecost;
+ if (p1->deletecost <= cost)
+ {
+ cost = p1->deletecost;
+ p->deletecount = p1->deletecount + 1;
+ }
+ else
+ p->deletecount = 1;
+ p->deletecost = cost;
+ }
+}
+
- next = unchanged_at_top;
- for (i = qi - 1; i >= 0; i--)
+\f
+/* Perform insert-lines and delete-lines operations on CURRENT_MATRIX
+ according to the costs in MATRIX, using the direct scrolling method
+ which is used when the terminal supports setting a scroll window
+ (scroll_region_ok).
+
+ WINDOW_SIZE is the number of lines being considered for scrolling
+ and UNCHANGED_AT_TOP is the vpos of the first line being
+ considered. These two arguments can specify any contiguous range
+ of lines.
+
+ In the direct scrolling method, a new scroll window is selected
+ before each insertion or deletion, so that groups of lines can be
+ scrolled directly to their final vertical positions. This method
+ is described in more detail in calculate_direct_scrolling, where
+ the cost matrix for this approach is constructed. */
+
+static void
+do_direct_scrolling (current_matrix, cost_matrix, window_size,
+ unchanged_at_top)
+ struct glyph_matrix *current_matrix;
+ struct matrix_elt *cost_matrix;
+ int window_size;
+ int unchanged_at_top;
+{
+ struct matrix_elt *p;
+ int i, j;
+
+ /* A queue of deletions and insertions to be performed. */
+ struct alt_queue { int count, pos, window; };
+ struct alt_queue *queue_start = (struct alt_queue *)
+ alloca (window_size * sizeof *queue_start);
+ struct alt_queue *queue = queue_start;
+
+ /* Set to 1 if a terminal window has been set with
+ set_terminal_window: */
+ int terminal_window_p = 0;
+
+ /* A nonzero value of write_follows indicates that a write has been
+ selected, allowing either an insert or a delete to be selected
+ next. When write_follows is zero, a delete cannot be selected
+ unless j < i, and an insert cannot be selected unless i < j.
+ This corresponds to a similar restriction (with the ordering
+ reversed) in calculate_direct_scrolling, which is intended to
+ ensure that lines marked as inserted will be blank. */
+ int write_follows_p = 1;
+
+ /* For each row in the new matrix what row of the old matrix it is. */
+ int *copy_from = (int *) alloca (window_size * sizeof (int));
+
+ /* Non-zero for each row in the new matrix that is retained from the
+ old matrix. Lines not retained are empty. */
+ char *retained_p = (char *) alloca (window_size * sizeof (char));
+
+ bzero (retained_p, window_size * sizeof (char));
+
+ /* Perform some sanity checks when GLYPH_DEBUG is on. */
+ CHECK_MATRIX (current_matrix);
+
+ /* We are working on the line range UNCHANGED_AT_TOP ...
+ UNCHANGED_AT_TOP + WINDOW_SIZE (not including) in CURRENT_MATRIX.
+ We step through lines in this range from the end to the start. I
+ is an index into new lines, j an index into old lines. The cost
+ matrix determines what to do for ranges of indices.
+
+ If i is decremented without also decrementing j, this corresponds
+ to inserting empty lines in the result. If j is decremented
+ without also decrementing i, this corresponds to omitting these
+ lines in the new rows, i.e. rows are deleted. */
+ i = j = window_size;
+
+ while (i > 0 || j > 0)
{
- ins_del_lines (queue[i].pos, queue[i].count);
-
- /* Mark the inserted lines as clear,
- and put into them the line-contents strings
- that were discarded during the deletions.
- Those are the ones for which temp_frame->enable was not set. */
- tem = queue[i].pos;
- for (j = tem + queue[i].count - 1; j >= tem; j--)
+ p = cost_matrix + i * (window_size + 1) + j;
+
+ if (p->insertcost < p->writecost
+ && p->insertcost < p->deletecost
+ && (write_follows_p || i < j))
+ {
+ /* Insert is cheaper than deleting or writing lines. Leave
+ a hole in the result display that will be filled with
+ empty lines when the queue is emptied. */
+ queue->count = 0;
+ queue->window = i;
+ queue->pos = i - p->insertcount;
+ ++queue;
+
+ i -= p->insertcount;
+ write_follows_p = 0;
+ }
+ else if (p->deletecost < p->writecost
+ && (write_follows_p || i > j))
+ {
+ /* Deleting lines is cheaper. By decrementing J, omit
+ deletecount lines from the original. */
+ write_follows_p = 0;
+ j -= p->deletecount;
+ }
+ else
{
- current_frame->enable[j] = 0;
- while (temp_frame->enable[next])
- next++;
- current_frame->glyphs[j] = temp_frame->glyphs[next];
- current_frame->charstarts[j] = temp_frame->charstarts[next++];
+ /* One or more lines should be written. In the direct
+ scrolling method we do this by scrolling the lines to the
+ place they belong. */
+ int n_to_write = p->writecount;
+ write_follows_p = 1;
+ xassert (n_to_write > 0);
+
+ if (i > j)
+ {
+ /* Immediately insert lines */
+ set_terminal_window (i + unchanged_at_top);
+ terminal_window_p = 1;
+ ins_del_lines (j - n_to_write + unchanged_at_top, i - j);
+ }
+ else if (i < j)
+ {
+ /* Queue the deletion of a group of lines */
+ queue->pos = i - n_to_write + unchanged_at_top;
+ queue->window = j + unchanged_at_top;
+ queue->count = i - j;
+ ++queue;
+ }
+
+ while (n_to_write > 0)
+ {
+ --i, --j, --n_to_write;
+ copy_from[i] = j;
+ retained_p[j] = 1;
+ }
}
}
- if (window)
+ /* Do queued operations. */
+ if (queue > queue_start)
+ {
+ int next = -1;
+
+ do
+ {
+ --queue;
+ if (queue->count)
+ {
+ set_terminal_window (queue->window);
+ terminal_window_p = 1;
+ ins_del_lines (queue->pos, queue->count);
+ }
+ else
+ {
+ for (j = queue->window - 1; j >= queue->pos; --j)
+ {
+ while (retained_p[++next])
+ ;
+ copy_from[j] = next;
+ }
+ }
+ }
+ while (queue > queue_start);
+ }
+
+ /* Now, for each row I in the range of rows we are working on,
+ copy_from[i] gives the original line to copy to I, and
+ retained_p[copy_from[i]] is zero if line I in the new display is
+ empty. */
+ mirrored_line_dance (current_matrix, unchanged_at_top, window_size,
+ copy_from, retained_p);
+
+ if (terminal_window_p)
set_terminal_window (0);
}
+
+
\f
void
scrolling_1 (frame, window_size, unchanged_at_top, unchanged_at_bottom,
- draw_cost, old_hash, new_hash, free_at_end)
+ draw_cost, old_draw_cost, old_hash, new_hash, free_at_end)
FRAME_PTR frame;
int window_size, unchanged_at_top, unchanged_at_bottom;
int *draw_cost;
+ int *old_draw_cost;
int *old_hash;
int *new_hash;
int free_at_end;
matrix = ((struct matrix_elt *)
alloca ((window_size + 1) * (window_size + 1) * sizeof *matrix));
- calculate_scrolling (frame, matrix, window_size, unchanged_at_bottom,
- draw_cost, old_hash, new_hash,
- free_at_end);
- do_scrolling (frame, matrix, window_size, unchanged_at_top);
+ if (scroll_region_ok)
+ {
+ calculate_direct_scrolling (frame, matrix, window_size,
+ unchanged_at_bottom,
+ draw_cost, old_draw_cost,
+ old_hash, new_hash, free_at_end);
+ do_direct_scrolling (frame->current_matrix,
+ matrix, window_size, unchanged_at_top);
+ }
+ else
+ {
+ calculate_scrolling (frame, matrix, window_size, unchanged_at_bottom,
+ draw_cost, old_hash, new_hash,
+ free_at_end);
+ do_scrolling (frame->current_matrix, matrix, window_size,
+ unchanged_at_top);
+ }
}
+
+
\f
-/* Return number of lines in common between current and desired frame contents
- described to us only as vectors of hash codes OLDHASH and NEWHASH.
- Consider only vpos range START to END (not including END).
- Ignore short lines on the assumption that
- avoiding redrawing such a line will have little weight. */
+/* Return number of lines in common between current and desired frame
+ contents described to us only as vectors of hash codes OLDHASH and
+ NEWHASH. Consider only vpos range START to END (not including
+ END). Ignore short lines on the assumption that avoiding redrawing
+ such a line will have little weight. */
int
scrolling_max_lines_saved (start, end, oldhash, newhash, cost)
bzero (lines, sizeof lines);
- /* Put new lines' hash codes in hash table.
- Ignore lines shorter than the threshold.
- Thus, if the lines that are in common
- are mainly the ones that are short,
- they won't count. */
+ /* Put new lines' hash codes in hash table. Ignore lines shorter
+ than the threshold. Thus, if the lines that are in common are
+ mainly the ones that are short, they won't count. */
for (i = start; i < end; i++)
{
if (cost[i] > threshold)
}
}
- /* Look up old line hash codes in the hash table.
- Count number of matches between old lines and new. */
-
+ /* Look up old line hash codes in the hash table. Count number of
+ matches between old lines and new. */
for (i = start; i < end; i++)
{
h = oldhash[i] & 0777;
return matchcount;
}
\f
-/* Return a measure of the cost of moving the lines
- starting with vpos FROM, up to but not including vpos TO,
- down by AMOUNT lines (AMOUNT may be negative).
- These are the same arguments that might be given to
- scroll_frame_lines to perform this scrolling. */
+/* Return a measure of the cost of moving the lines starting with vpos
+ FROM, up to but not including vpos TO, down by AMOUNT lines (AMOUNT
+ may be negative). These are the same arguments that might be given
+ to scroll_frame_lines to perform this scrolling. */
+int
scroll_cost (frame, from, to, amount)
FRAME_PTR frame;
int from, to, amount;
return
(FRAME_INSERT_COST (frame)[offset + from]
+ (amount - 1) * FRAME_INSERTN_COST (frame)[offset + from]
- + FRAME_DELETEN_COST (frame)[offset + to]
- + (amount - 1) * FRAME_DELETE_COST (frame)[offset + to]);
+ + FRAME_DELETE_COST (frame)[offset + to]
+ + (amount - 1) * FRAME_DELETEN_COST (frame)[offset + to]);
}
\f
/* Calculate the line insertion/deletion
Deletion is essentially the same as insertion.
*/
+void
do_line_insertion_deletion_costs (frame,
ins_line_string, multi_ins_string,
del_line_string, multi_del_string,
ins_del_costs (frame,
del_line_string, multi_del_string,
setup_string, cleanup_string,
- FRAME_DELETEN_COST (frame), FRAME_DELETE_COST (frame),
+ FRAME_DELETE_COST (frame), FRAME_DELETEN_COST (frame),
coefficient);
}