1 /* PSPP - a program for statistical analysis.
2 Copyright (C) 2009, 2010, 2011, 2013, 2014, 2016 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation, either version 3 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
25 #include "libpspp/assertion.h"
26 #include "libpspp/hash-functions.h"
27 #include "libpspp/hmap.h"
28 #include "libpspp/pool.h"
29 #include "output/render.h"
30 #include "output/table-item.h"
31 #include "output/table.h"
33 #include "gl/minmax.h"
34 #include "gl/xalloc.h"
37 #define _(msgid) gettext (msgid)
39 /* This file uses TABLE_HORZ and TABLE_VERT enough to warrant abbreviating. */
43 /* A layout for rendering a specific table on a specific device.
45 May represent the layout of an entire table presented to
46 render_page_create(), or a rectangular subregion of a table broken out using
47 render_break_next() to allow a table to be broken across multiple pages.
49 A page's size is not limited to the size passed in as part of render_params.
50 render_pager breaks a render_page into smaller render_pages that will fit in
51 the available space. */
54 const struct render_params *params; /* Parameters of the target device. */
55 struct table *table; /* Table rendered. */
58 /* Region of 'table' to render.
60 The horizontal cells rendered are the leftmost h[H][0], then
61 r[H][0] through r[H][1], exclusive, then the rightmost h[H][1].
63 The vertical cells rendered are the topmost h[V][0], then r[V][0]
64 through r[V][1], exclusive, then the bottommost h[V][1].
66 n[H] = h[H][0] + (r[H][1] - r[H][0]) + h[H][1]
67 n[V] = h[V][0] + (r[V][1] - r[V][0]) + h[V][1]
69 int h[TABLE_N_AXES][2];
70 int r[TABLE_N_AXES][2];
75 cp[H] represents x positions within the table.
77 cp[H][1] = the width of the leftmost vertical rule.
78 cp[H][2] = cp[H][1] + the width of the leftmost column.
79 cp[H][3] = cp[H][2] + the width of the second-from-left vertical rule.
81 cp[H][2 * nc] = x position of the rightmost vertical rule.
82 cp[H][2 * nc + 1] = total table width including all rules.
84 Similarly, cp[V] represents y positions within the table.
86 cp[V][1] = the height of the topmost horizontal rule.
87 cp[V][2] = cp[V][1] + the height of the topmost row.
88 cp[V][3] = cp[V][2] + the height of the second-from-top horizontal rule.
90 cp[V][2 * nr] = y position of the bottommost horizontal rule.
91 cp[V][2 * nr + 1] = total table height including all rules.
93 Rules and columns can have width or height 0, in which case consecutive
94 values in this array are equal. */
95 int *cp[TABLE_N_AXES];
97 /* render_break_next() can break a table such that some cells are not fully
98 contained within a render_page. This will happen if a cell is too wide
99 or two tall to fit on a single page, or if a cell spans multiple rows or
100 columns and the page only includes some of those rows or columns.
102 This hash table contains "struct render_overflow"s that represents each
103 such cell that doesn't completely fit on this page.
105 Each overflow cell borders at least one header edge of the table and may
106 border more. (A single table cell that is so large that it fills the
107 entire page can overflow on all four sides!) */
108 struct hmap overflows;
110 /* If a single column (or row) is too wide (or tall) to fit on a page
111 reasonably, then render_break_next() will split a single row or column
112 across multiple render_pages. This member indicates when this has
115 is_edge_cutoff[H][0] is true if pixels have been cut off the left side
116 of the leftmost column in this page, and false otherwise.
118 is_edge_cutoff[H][1] is true if pixels have been cut off the right side
119 of the rightmost column in this page, and false otherwise.
121 is_edge_cutoff[V][0] and is_edge_cutoff[V][1] are similar for the top
122 and bottom of the table.
124 The effect of is_edge_cutoff is to prevent rules along the edge in
125 question from being rendered.
127 When is_edge_cutoff is true for a given edge, the 'overflows' hmap will
128 contain a node for each cell along that edge. */
129 bool is_edge_cutoff[TABLE_N_AXES][2];
131 /* If part of a joined cell would be cut off by breaking a table along
132 'axis' at the rule with offset 'z' (where 0 <= z <= n[axis]), then
133 join_crossing[axis][z] is the thickness of the rule that would be cut
136 This is used to know to allocate extra space for breaking at such a
137 position, so that part of the cell's content is not lost.
139 This affects breaking a table only when headers are present. When
140 headers are not present, the rule's thickness is used for cell content,
141 so no part of the cell's content is lost (and in fact it is duplicated
142 across both pages). */
143 int *join_crossing[TABLE_N_AXES];
146 static struct render_page *render_page_create (const struct render_params *,
147 struct table *, int min_width);
149 struct render_page *render_page_ref (const struct render_page *page_);
150 static void render_page_unref (struct render_page *);
152 /* Returns the offset in struct render_page's cp[axis] array of the rule with
153 index RULE_IDX. That is, if RULE_IDX is 0, then the offset is that of the
154 leftmost or topmost rule; if RULE_IDX is 1, then the offset is that of the
155 next rule to the right (or below); and so on. */
157 rule_ofs (int rule_idx)
162 /* Returns the offset in struct render_page's cp[axis] array of the rule with
163 index RULE_IDX_R, which counts from the right side (or bottom) of the page
164 left (or up), according to whether AXIS is H or V, respectively. That is,
165 if RULE_IDX_R is 0, then the offset is that of the rightmost or bottommost
166 rule; if RULE_IDX is 1, then the offset is that of the next rule to the left
167 (or above); and so on. */
169 rule_ofs_r (const struct render_page *page, int axis, int rule_idx_r)
171 return (page->n[axis] - rule_idx_r) * 2;
174 /* Returns the offset in struct render_page's cp[axis] array of the cell with
175 index CELL_IDX. That is, if CELL_IDX is 0, then the offset is that of the
176 leftmost or topmost cell; if CELL_IDX is 1, then the offset is that of the
177 next cell to the right (or below); and so on. */
179 cell_ofs (int cell_idx)
181 return cell_idx * 2 + 1;
184 /* Returns the width of PAGE along AXIS from OFS0 to OFS1, exclusive. */
186 axis_width (const struct render_page *page, int axis, int ofs0, int ofs1)
188 return page->cp[axis][ofs1] - page->cp[axis][ofs0];
191 /* Returns the width of the headers in PAGE along AXIS. */
193 headers_width (const struct render_page *page, int axis)
195 int h0 = page->h[axis][0];
196 int w0 = axis_width (page, axis, rule_ofs (0), cell_ofs (h0));
197 int n = page->n[axis];
198 int h1 = page->h[axis][1];
199 int w1 = axis_width (page, axis, rule_ofs_r (page, axis, h1), cell_ofs (n));
203 /* Returns the width of cell X along AXIS in PAGE. */
205 cell_width (const struct render_page *page, int axis, int x)
207 return axis_width (page, axis, cell_ofs (x), cell_ofs (x) + 1);
210 /* Returns the width of rule X along AXIS in PAGE. */
212 rule_width (const struct render_page *page, int axis, int x)
214 return axis_width (page, axis, rule_ofs (x), rule_ofs (x) + 1);
217 /* Returns the width of rule X along AXIS in PAGE. */
219 rule_width_r (const struct render_page *page, int axis, int x)
221 int ofs = rule_ofs_r (page, axis, x);
222 return axis_width (page, axis, ofs, ofs + 1);
225 /* Returns the width of cells X0 through X1, exclusive, along AXIS in PAGE. */
227 joined_width (const struct render_page *page, int axis, int x0, int x1)
229 return axis_width (page, axis, cell_ofs (x0), cell_ofs (x1) - 1);
232 /* Returns the width of the widest cell, excluding headers, along AXIS in
235 max_cell_width (const struct render_page *page, int axis)
237 int n = page->n[axis];
238 int x0 = page->h[axis][0];
239 int x1 = n - page->h[axis][1];
242 for (int x = x0; x < x1; x++)
244 int w = cell_width (page, axis, x);
251 /* A cell that doesn't completely fit on the render_page. */
252 struct render_overflow
254 struct hmap_node node; /* In render_page's 'overflows' hmap. */
256 /* Occupied region of page.
258 d[H][0] is the leftmost column.
259 d[H][1] is the rightmost column, plus 1.
260 d[V][0] is the top row.
261 d[V][1] is the bottom row, plus 1.
263 The cell in its original table might occupy a larger region. This
264 member reflects the size of the cell in the current render_page, after
265 trimming off any rows or columns due to page-breaking. */
268 /* The space that has been trimmed off the cell:
270 overflow[H][0]: space trimmed off its left side.
271 overflow[H][1]: space trimmed off its right side.
272 overflow[V][0]: space trimmed off its top.
273 overflow[V][1]: space trimmed off its bottom.
275 During rendering, this information is used to position the rendered
276 portion of the cell within the available space.
278 When a cell is rendered, sometimes it is permitted to spill over into
279 space that is ordinarily reserved for rules. Either way, this space is
280 still included in overflow values.
282 Suppose, for example, that a cell that joins 2 columns has a width of 60
283 pixels and content "abcdef", that the 2 columns that it joins have
284 widths of 20 and 30 pixels, respectively, and that therefore the rule
285 between the two joined columns has a width of 10 (20 + 10 + 30 = 60).
286 It might render like this, if each character is 10x10, and showing a few
287 extra table cells for context:
295 If this render_page is broken at the rule that separates "gh" from
296 "ijk", then the page that contains the left side of the "abcdef" cell
297 will have overflow[H][1] of 10 + 30 = 40 for its portion of the cell,
298 and the page that contains the right side of the cell will have
299 overflow[H][0] of 20 + 10 = 30. The two resulting pages would look like
317 int overflow[TABLE_N_AXES][2];
320 /* Returns a hash value for (,Y). */
322 hash_cell (int x, int y)
324 return hash_int (x + (y << 16), 0);
327 /* Searches PAGE's set of render_overflow for one whose top-left cell is
328 (X,Y). Returns it, if there is one, otherwise a null pointer. */
329 static const struct render_overflow *
330 find_overflow (const struct render_page *page, int x, int y)
332 if (!hmap_is_empty (&page->overflows))
334 const struct render_overflow *of;
336 HMAP_FOR_EACH_WITH_HASH (of, struct render_overflow, node,
337 hash_cell (x, y), &page->overflows)
338 if (x == of->d[H] && y == of->d[V])
345 /* Row or column dimensions. Used to figure the size of a table in
346 render_page_create() and discarded after that. */
349 /* Width without considering rows (or columns) that span more than one (or
353 /* Width taking spanned rows (or columns) into consideration. */
357 /* Modifies the 'width' members of the N elements of ROWS so that their sum,
358 when added to rule widths RULES[1] through RULES[N - 1] inclusive, is at
361 distribute_spanned_width (int width,
362 struct render_row *rows, const int *rules, int n)
364 /* Sum up the unspanned widths of the N rows for use as weights. */
365 int total_unspanned = 0;
366 for (int x = 0; x < n; x++)
367 total_unspanned += rows[x].unspanned;
368 for (int x = 0; x < n - 1; x++)
369 total_unspanned += rules[x + 1];
370 if (total_unspanned >= width)
373 /* The algorithm used here is based on the following description from HTML 4:
375 For cells that span multiple columns, a simple approach consists of
376 apportioning the min/max widths evenly to each of the constituent
377 columns. A slightly more complex approach is to use the min/max
378 widths of unspanned cells to weight how spanned widths are
379 apportioned. Experiments suggest that a blend of the two approaches
380 gives good results for a wide range of tables.
382 We blend the two approaches half-and-half, except that we cannot use the
383 unspanned weights when 'total_unspanned' is 0 (because that would cause a
386 The calculation we want to do is this:
389 w1 = width * (column's unspanned width) / (total unspanned width)
390 (column's width) = (w0 + w1) / 2
392 We implement it as a precise calculation in integers by multiplying w0 and
393 w1 by the common denominator of all three calculations (d), dividing that
394 out in the column width calculation, and then keeping the remainder for
397 (We actually compute the unspanned width of a column as twice the
398 unspanned width, plus the width of the rule on the left, plus the width of
399 the rule on the right. That way each rule contributes to both the cell on
400 its left and on its right.)
402 long long int d0 = n;
403 long long int d1 = 2LL * MAX (total_unspanned, 1);
404 long long int d = d0 * d1;
405 if (total_unspanned > 0)
407 long long int w = d / 2;
408 for (int x = 0; x < n; x++)
411 if (total_unspanned > 0)
413 long long int unspanned = rows[x].unspanned * 2LL;
415 unspanned += rules[x + 1];
417 unspanned += rules[x];
418 w += width * unspanned * d0;
421 rows[x].width = MAX (rows[x].width, w / d);
422 w -= rows[x].width * d;
426 /* Initializes PAGE->cp[AXIS] from the row widths in ROWS and the rule widths
429 accumulate_row_widths (const struct render_page *page, enum table_axis axis,
430 const struct render_row *rows, const int *rules)
432 int n = page->n[axis];
433 int *cp = page->cp[axis];
435 for (int z = 0; z < n; z++)
437 cp[1] = cp[0] + rules[z];
438 cp[2] = cp[1] + rows[z].width;
441 cp[1] = cp[0] + rules[n];
444 /* Returns the sum of widths of the N ROWS and N+1 RULES. */
446 calculate_table_width (int n, const struct render_row *rows, int *rules)
449 for (int x = 0; x < n; x++)
450 width += rows[x].width;
451 for (int x = 0; x <= n; x++)
457 /* Rendering utility functions. */
459 /* Returns the line style to use for drawing a rule of the given TYPE. */
460 static enum render_line_style
461 rule_to_render_type (unsigned char type)
465 case TABLE_STROKE_NONE:
466 return RENDER_LINE_NONE;
467 case TABLE_STROKE_SOLID:
468 return RENDER_LINE_SINGLE;
469 case TABLE_STROKE_DASHED:
470 return RENDER_LINE_DASHED;
471 case TABLE_STROKE_THICK:
472 return RENDER_LINE_THICK;
473 case TABLE_STROKE_THIN:
474 return RENDER_LINE_THIN;
475 case TABLE_STROKE_DOUBLE:
476 return RENDER_LINE_DOUBLE;
482 /* Returns the width of the rule in TABLE that is at offset Z along axis A, if
483 rendered with PARAMS. */
485 measure_rule (const struct render_params *params, const struct table *table,
486 enum table_axis a, int z)
488 enum table_axis b = !a;
490 /* Determine all types of rules that are present, as a bitmap in 'rules'
491 where rule type 't' is present if bit 2**t is set. */
492 struct cell_color color;
493 unsigned int rules = 0;
496 for (d[b] = 0; d[b] < table->n[b]; d[b]++)
497 rules |= 1u << table_get_rule (table, a, d[H], d[V], &color);
499 /* Turn off TABLE_STROKE_NONE because it has width 0 and we needn't bother.
500 However, if the device doesn't support margins, make sure that there is at
501 least a small gap between cells (but we don't need any at the left or
502 right edge of the table). */
503 if (rules & (1u << TABLE_STROKE_NONE))
505 rules &= ~(1u << TABLE_STROKE_NONE);
506 if (z > 0 && z < table->n[a] && !params->supports_margins && a == H)
507 rules |= 1u << TABLE_STROKE_SOLID;
510 /* Calculate maximum width of the rules that are present. */
512 for (size_t i = 0; i < TABLE_N_STROKES; i++)
513 if (rules & (1u << i))
514 width = MAX (width, params->line_widths[a][rule_to_render_type (i)]);
518 /* Allocates and returns a new render_page using PARAMS and TABLE. Allocates
519 space for rendering a table with dimensions given in N. The caller must
520 initialize most of the members itself. */
521 static struct render_page *
522 render_page_allocate__ (const struct render_params *params,
523 struct table *table, int n[TABLE_N_AXES])
525 struct render_page *page = xmalloc (sizeof *page);
526 page->params = params;
532 for (int i = 0; i < TABLE_N_AXES; i++)
534 page->cp[i] = xmalloc ((2 * n[i] + 2) * sizeof *page->cp[i]);
535 page->join_crossing[i] = xzalloc ((n[i] + 1)
536 * sizeof *page->join_crossing[i]);
539 hmap_init (&page->overflows);
540 memset (page->is_edge_cutoff, 0, sizeof page->is_edge_cutoff);
545 /* Allocates and returns a new render_page using PARAMS and TABLE. Allocates
546 space for all of the members of the new page, but the caller must initialize
547 the 'cp' member itself. */
548 static struct render_page *
549 render_page_allocate (const struct render_params *params, struct table *table)
551 struct render_page *page = render_page_allocate__ (params, table, table->n);
552 for (enum table_axis a = 0; a < TABLE_N_AXES; a++)
554 page->h[a][0] = table->h[a][0];
555 page->h[a][1] = table->h[a][1];
556 page->r[a][0] = table->h[a][0];
557 page->r[a][1] = table->n[a] - table->h[a][1];
562 /* Allocates and returns a new render_page for PARAMS and TABLE, initializing
563 cp[H] in the new page from ROWS and RULES. The caller must still initialize
565 static struct render_page *
566 create_page_with_exact_widths (const struct render_params *params,
568 const struct render_row *rows, int *rules)
570 struct render_page *page = render_page_allocate (params, table);
571 accumulate_row_widths (page, H, rows, rules);
575 /* Allocates and returns a new render_page for PARAMS and TABLE.
577 Initializes cp[H] in the new page by setting the width of each row 'i' to
578 somewhere between the minimum cell width ROW_MIN[i].width and the maximum
579 ROW_MAX[i].width. Sets the width of rules to those in RULES.
581 W_MIN is the sum of ROWS_MIN[].width.
583 W_MAX is the sum of ROWS_MAX[].width.
585 The caller must still initialize cp[V]. */
586 static struct render_page *
587 create_page_with_interpolated_widths (const struct render_params *params,
589 const struct render_row *rows_min,
590 const struct render_row *rows_max,
591 int w_min, int w_max, const int *rules)
593 const int n = table->n[H];
594 const long long int avail = params->size[H] - w_min;
595 const long long int wanted = w_max - w_min;
599 struct render_page *page = render_page_allocate (params, table);
601 int *cph = page->cp[H];
603 long long int w = wanted / 2;
604 for (int x = 0; x < n; x++)
606 w += avail * (rows_max[x].width - rows_min[x].width);
607 int extra = w / wanted;
610 cph[1] = cph[0] + rules[x];
611 cph[2] = cph[1] + rows_min[x].width + extra;
614 cph[1] = cph[0] + rules[n];
616 assert (page->cp[H][n * 2 + 1] == params->size[H]);
621 set_join_crossings (struct render_page *page, enum table_axis axis,
622 const struct table_cell *cell, int *rules)
624 for (int z = cell->d[axis][0] + 1; z <= cell->d[axis][1] - 1; z++)
625 page->join_crossing[axis][z] = rules[z];
628 /* Maps a contiguous range of cells from a page to the underlying table along
629 the horizpntal or vertical dimension. */
632 int p0; /* First ordinate in the page. */
633 int t0; /* First ordinate in the table. */
634 int n; /* Number of ordinates in page and table. */
637 /* Initializes M to a mapping from PAGE to PAGE->table along axis A. The
638 mapping includes ordinate Z (in PAGE). */
640 get_map (const struct render_page *page, enum table_axis a, int z,
643 if (z < page->h[a][0])
647 m->n = page->h[a][0];
649 else if (z < page->n[a] - page->h[a][1])
651 m->p0 = page->h[a][0];
652 m->t0 = page->r[a][0];
653 m->n = page->r[a][1] - page->r[a][0];
657 m->p0 = page->n[a] - page->h[a][1];
658 m->t0 = page->table->n[a] - page->table->h[a][1];
659 m->n = page->h[a][1];
663 /* Initializes CELL with the contents of the table cell at column X and row Y
664 within PAGE. When CELL is no longer needed, the caller is responsible for
665 freeing it by calling table_cell_free(CELL).
667 The caller must ensure that CELL is destroyed before TABLE is unref'ed.
669 This is equivalent to table_get_cell(), except X and Y are in terms of the
670 page's rows and columns rather than the underlying table's. */
672 render_get_cell (const struct render_page *page, int x, int y,
673 struct table_cell *cell)
675 int d[TABLE_N_AXES] = { [H] = x, [V] = y };
676 struct map map[TABLE_N_AXES];
678 for (enum table_axis a = 0; a < TABLE_N_AXES; a++)
680 struct map *m = &map[a];
681 get_map (page, a, d[a], m);
682 d[a] += m->t0 - m->p0;
684 table_get_cell (page->table, d[H], d[V], cell);
686 for (enum table_axis a = 0; a < TABLE_N_AXES; a++)
688 struct map *m = &map[a];
690 for (int i = 0; i < 2; i++)
691 cell->d[a][i] -= m->t0 - m->p0;
692 cell->d[a][0] = MAX (cell->d[a][0], m->p0);
693 cell->d[a][1] = MIN (cell->d[a][1], m->p0 + m->n);
697 /* Creates and returns a new render_page for rendering TABLE on a device
700 The new render_page will be suitable for rendering on a device whose page
701 size is PARAMS->size, but the caller is responsible for actually breaking it
702 up to fit on such a device, using the render_break abstraction. */
703 static struct render_page *
704 render_page_create (const struct render_params *params, struct table *table,
709 int nc = table_nc (table);
710 int nr = table_nr (table);
712 /* Figure out rule widths. */
713 int *rules[TABLE_N_AXES];
714 for (enum table_axis axis = 0; axis < TABLE_N_AXES; axis++)
716 int n = table->n[axis] + 1;
718 rules[axis] = xnmalloc (n, sizeof *rules);
719 for (int z = 0; z < n; z++)
720 rules[axis][z] = measure_rule (params, table, axis, z);
723 /* Calculate minimum and maximum widths of cells that do not
724 span multiple columns. */
725 struct render_row *columns[2];
726 for (int i = 0; i < 2; i++)
727 columns[i] = xzalloc (nc * sizeof *columns[i]);
728 for (int y = 0; y < nr; y++)
729 for (int x = 0; x < nc;)
731 struct table_cell cell;
733 table_get_cell (table, x, y, &cell);
734 if (y == cell.d[V][0])
736 if (table_cell_colspan (&cell) == 1)
739 params->measure_cell_width (params->aux, &cell,
741 for (int i = 0; i < 2; i++)
742 if (columns[i][x].unspanned < w[i])
743 columns[i][x].unspanned = w[i];
749 /* Distribute widths of spanned columns. */
750 for (int i = 0; i < 2; i++)
751 for (int x = 0; x < nc; x++)
752 columns[i][x].width = columns[i][x].unspanned;
753 for (int y = 0; y < nr; y++)
754 for (int x = 0; x < nc;)
756 struct table_cell cell;
758 table_get_cell (table, x, y, &cell);
759 if (y == cell.d[V][0] && table_cell_colspan (&cell) > 1)
763 params->measure_cell_width (params->aux, &cell, &w[MIN], &w[MAX]);
764 for (int i = 0; i < 2; i++)
765 distribute_spanned_width (w[i], &columns[i][cell.d[H][0]],
766 rules[H], table_cell_colspan (&cell));
771 for (int i = 0; i < 2; i++)
772 distribute_spanned_width (min_width, &columns[i][0], rules[H], nc);
774 /* In pathological cases, spans can cause the minimum width of a column to
775 exceed the maximum width. This bollixes our interpolation algorithm
776 later, so fix it up. */
777 for (int i = 0; i < nc; i++)
778 if (columns[MIN][i].width > columns[MAX][i].width)
779 columns[MAX][i].width = columns[MIN][i].width;
781 /* Decide final column widths. */
783 for (int i = 0; i < 2; i++)
784 table_widths[i] = calculate_table_width (table_nc (table),
785 columns[i], rules[H]);
787 struct render_page *page;
788 if (table_widths[MAX] <= params->size[H])
790 /* Fits even with maximum widths. Use them. */
791 page = create_page_with_exact_widths (params, table, columns[MAX],
794 else if (table_widths[MIN] <= params->size[H])
796 /* Fits with minimum widths, so distribute the leftover space. */
797 page = create_page_with_interpolated_widths (
798 params, table, columns[MIN], columns[MAX],
799 table_widths[MIN], table_widths[MAX], rules[H]);
803 /* Doesn't fit even with minimum widths. Assign minimums for now, and
804 later we can break it horizontally into multiple pages. */
805 page = create_page_with_exact_widths (params, table, columns[MIN],
809 /* Calculate heights of cells that do not span multiple rows. */
810 struct render_row *rows = xzalloc (nr * sizeof *rows);
811 for (int y = 0; y < nr; y++)
812 for (int x = 0; x < nc;)
814 struct render_row *r = &rows[y];
815 struct table_cell cell;
817 render_get_cell (page, x, y, &cell);
818 if (y == cell.d[V][0])
820 if (table_cell_rowspan (&cell) == 1)
822 int w = joined_width (page, H, cell.d[H][0], cell.d[H][1]);
823 int h = params->measure_cell_height (params->aux, &cell, w);
824 if (h > r->unspanned)
825 r->unspanned = r->width = h;
828 set_join_crossings (page, V, &cell, rules[V]);
830 if (table_cell_colspan (&cell) > 1)
831 set_join_crossings (page, H, &cell, rules[H]);
835 for (int i = 0; i < 2; i++)
838 /* Distribute heights of spanned rows. */
839 for (int y = 0; y < nr; y++)
840 for (int x = 0; x < nc;)
842 struct table_cell cell;
844 render_get_cell (page, x, y, &cell);
845 if (y == cell.d[V][0] && table_cell_rowspan (&cell) > 1)
847 int w = joined_width (page, H, cell.d[H][0], cell.d[H][1]);
848 int h = params->measure_cell_height (params->aux, &cell, w);
849 distribute_spanned_width (h, &rows[cell.d[V][0]], rules[V],
850 table_cell_rowspan (&cell));
855 /* Decide final row heights. */
856 accumulate_row_widths (page, V, rows, rules[V]);
859 /* Measure headers. If they are "too big", get rid of them. */
860 for (enum table_axis axis = 0; axis < TABLE_N_AXES; axis++)
862 int hw = headers_width (page, axis);
863 if (hw * 2 >= page->params->size[axis]
864 || hw + max_cell_width (page, axis) > page->params->size[axis])
866 page->h[axis][0] = page->h[axis][1] = 0;
867 page->r[axis][0] = 0;
868 page->r[axis][1] = page->n[axis];
878 /* Increases PAGE's reference count. */
880 render_page_ref (const struct render_page *page_)
882 struct render_page *page = CONST_CAST (struct render_page *, page_);
887 /* Decreases PAGE's reference count and destroys PAGE if this causes the
888 reference count to fall to zero. */
890 render_page_unref (struct render_page *page)
892 if (page != NULL && --page->ref_cnt == 0)
894 struct render_overflow *overflow, *next;
895 HMAP_FOR_EACH_SAFE (overflow, next, struct render_overflow, node,
898 hmap_destroy (&page->overflows);
900 table_unref (page->table);
902 for (int i = 0; i < TABLE_N_AXES; ++i)
904 free (page->join_crossing[i]);
912 /* Returns the size of PAGE along AXIS. (This might be larger than the page
913 size specified in the parameters passed to render_page_create(). Use a
914 render_break to break up a render_page into page-sized chunks.) */
916 render_page_get_size (const struct render_page *page, enum table_axis axis)
918 return page->cp[axis][page->n[axis] * 2 + 1];
922 render_page_get_best_breakpoint (const struct render_page *page, int height)
924 /* If there's no room for at least the top row and the rules above and below
925 it, don't include any of the table. */
926 if (page->cp[V][3] > height)
929 /* Otherwise include as many rows and rules as we can. */
930 for (int y = 5; y <= 2 * page->n[V] + 1; y += 2)
931 if (page->cp[V][y] > height)
932 return page->cp[V][y - 2];
936 /* Drawing render_pages. */
938 /* This is like table_get_rule() except:
940 - D is in terms of the page's rows and column rather than the underlying
943 - The result is in the form of a render_line_style. */
944 static enum render_line_style
945 get_rule (const struct render_page *page, enum table_axis axis,
946 const int d_[TABLE_N_AXES], struct cell_color *color)
948 int d[TABLE_N_AXES] = { d_[0] / 2, d_[1] / 2 };
951 enum table_axis a = axis;
952 if (d[a] < page->h[a][0])
954 else if (d[a] <= page->n[a] - page->h[a][1])
956 if (page->h[a][0] && d[a] == page->h[a][0])
958 else if (page->h[a][1] && d[a] == page->n[a] - page->h[a][1])
959 d2 = page->table->n[a] - page->h[a][1];
960 d[a] += page->r[a][0] - page->h[a][0];
963 d[a] += ((page->table->n[a] - page->table->h[a][1])
964 - (page->n[a] - page->h[a][1]));
966 enum table_axis b = !axis;
968 get_map (page, b, d[b], &m);
971 int r = table_get_rule (page->table, axis, d[H], d[V], color);
975 int r2 = table_get_rule (page->table, axis, d[H], d[V], color);
976 r = table_stroke_combine (r, r2);
978 return rule_to_render_type (r);
988 render_direction_rtl (void)
990 /* TRANSLATORS: Do not translate this string. If the script of your language
991 reads from right to left (eg Persian, Arabic, Hebrew etc), then replace
992 this string with "output-direction-rtl". Otherwise either leave it
993 untranslated or copy it verbatim. */
994 const char *dir = _("output-direction-ltr");
995 if (0 == strcmp ("output-direction-rtl", dir))
998 if (0 != strcmp ("output-direction-ltr", dir))
999 fprintf (stderr, "This localisation has been incorrectly translated. "
1000 "Complain to the translator.\n");
1006 render_rule (const struct render_page *page, const int ofs[TABLE_N_AXES],
1007 const int d[TABLE_N_AXES])
1009 enum render_line_style styles[TABLE_N_AXES][2];
1010 struct cell_color colors[TABLE_N_AXES][2];
1012 for (enum table_axis a = 0; a < TABLE_N_AXES; a++)
1014 enum table_axis b = !a;
1016 styles[a][0] = styles[a][1] = RENDER_LINE_NONE;
1019 || (page->is_edge_cutoff[a][0] && d[a] == 0)
1020 || (page->is_edge_cutoff[a][1] && d[a] == page->n[a] * 2))
1027 int e[TABLE_N_AXES];
1031 styles[a][0] = get_rule (page, a, e, &colors[a][0]);
1034 if (d[b] / 2 < page->n[b])
1035 styles[a][1] = get_rule (page, a, d, &colors[a][1]);
1039 styles[a][0] = styles[a][1] = get_rule (page, a, d, &colors[a][0]);
1040 colors[a][1] = colors[a][0];
1044 if (styles[H][0] != RENDER_LINE_NONE || styles[H][1] != RENDER_LINE_NONE
1045 || styles[V][0] != RENDER_LINE_NONE || styles[V][1] != RENDER_LINE_NONE)
1047 int bb[TABLE_N_AXES][2];
1049 bb[H][0] = ofs[H] + page->cp[H][d[H]];
1050 bb[H][1] = ofs[H] + page->cp[H][d[H] + 1];
1051 if (page->params->rtl)
1053 int temp = bb[H][0];
1054 bb[H][0] = render_page_get_size (page, H) - bb[H][1];
1055 bb[H][1] = render_page_get_size (page, H) - temp;
1057 bb[V][0] = ofs[V] + page->cp[V][d[V]];
1058 bb[V][1] = ofs[V] + page->cp[V][d[V] + 1];
1059 page->params->draw_line (page->params->aux, bb, styles, colors);
1064 render_cell (const struct render_page *page, const int ofs[TABLE_N_AXES],
1065 const struct table_cell *cell)
1067 int bb[TABLE_N_AXES][2];
1068 int clip[TABLE_N_AXES][2];
1070 bb[H][0] = clip[H][0] = ofs[H] + page->cp[H][cell->d[H][0] * 2 + 1];
1071 bb[H][1] = clip[H][1] = ofs[H] + page->cp[H][cell->d[H][1] * 2];
1072 if (page->params->rtl)
1074 int temp = bb[H][0];
1075 bb[H][0] = clip[H][0] = render_page_get_size (page, H) - bb[H][1];
1076 bb[H][1] = clip[H][1] = render_page_get_size (page, H) - temp;
1078 bb[V][0] = clip[V][0] = ofs[V] + page->cp[V][cell->d[V][0] * 2 + 1];
1079 bb[V][1] = clip[V][1] = ofs[V] + page->cp[V][cell->d[V][1] * 2];
1081 enum table_valign valign = cell->style->cell_style.valign;
1082 if (valign != TABLE_VALIGN_TOP)
1084 int height = page->params->measure_cell_height (
1085 page->params->aux, cell, bb[H][1] - bb[H][0]);
1086 int extra = bb[V][1] - bb[V][0] - height;
1089 if (valign == TABLE_VALIGN_CENTER)
1095 const struct render_overflow *of = find_overflow (
1096 page, cell->d[H][0], cell->d[V][0]);
1098 for (enum table_axis axis = 0; axis < TABLE_N_AXES; axis++)
1100 if (of->overflow[axis][0])
1102 bb[axis][0] -= of->overflow[axis][0];
1103 if (cell->d[axis][0] == 0 && !page->is_edge_cutoff[axis][0])
1104 clip[axis][0] = ofs[axis] + page->cp[axis][cell->d[axis][0] * 2];
1106 if (of->overflow[axis][1])
1108 bb[axis][1] += of->overflow[axis][1];
1109 if (cell->d[axis][1] == page->n[axis]
1110 && !page->is_edge_cutoff[axis][1])
1111 clip[axis][1] = ofs[axis] + page->cp[axis][cell->d[axis][1] * 2
1116 int spill[TABLE_N_AXES][2];
1117 for (enum table_axis axis = 0; axis < TABLE_N_AXES; axis++)
1119 spill[axis][0] = rule_width (page, axis, cell->d[axis][0]) / 2;
1120 spill[axis][1] = rule_width (page, axis, cell->d[axis][1]) / 2;
1123 int color_idx = (cell->d[V][0] < page->h[V][0]
1124 || page->n[V] - (cell->d[V][0] + 1) < page->h[V][1]
1126 : (cell->d[V][0] - page->h[V][0]) & 1);
1127 page->params->draw_cell (page->params->aux, cell, color_idx,
1131 /* Draws the cells of PAGE indicated in BB. */
1133 render_page_draw_cells (const struct render_page *page,
1134 int ofs[TABLE_N_AXES], int bb[TABLE_N_AXES][2])
1136 for (int y = bb[V][0]; y < bb[V][1]; y++)
1137 for (int x = bb[H][0]; x < bb[H][1];)
1138 if (!is_rule (x) && !is_rule (y))
1140 struct table_cell cell;
1142 render_get_cell (page, x / 2, y / 2, &cell);
1143 if (y / 2 == bb[V][0] / 2 || y / 2 == cell.d[V][0])
1144 render_cell (page, ofs, &cell);
1145 x = rule_ofs (cell.d[H][1]);
1150 for (int y = bb[V][0]; y < bb[V][1]; y++)
1151 for (int x = bb[H][0]; x < bb[H][1]; x++)
1152 if (is_rule (x) || is_rule (y))
1154 int d[TABLE_N_AXES];
1157 render_rule (page, ofs, d);
1161 /* Renders PAGE, by calling the 'draw_line' and 'draw_cell' functions from the
1162 render_params provided to render_page_create(). */
1164 render_page_draw (const struct render_page *page, int ofs[TABLE_N_AXES])
1166 int bb[TABLE_N_AXES][2];
1169 bb[H][1] = page->n[H] * 2 + 1;
1171 bb[V][1] = page->n[V] * 2 + 1;
1173 render_page_draw_cells (page, ofs, bb);
1176 /* Returns the greatest value i, 0 <= i < n, such that cp[i] <= x0. */
1178 get_clip_min_extent (int x0, const int cp[], int n)
1185 int middle = low + (high - low) / 2;
1187 if (cp[middle] <= x0)
1199 /* Returns the least value i, 0 <= i < n, such that cp[i] >= x1. */
1201 get_clip_max_extent (int x1, const int cp[], int n)
1208 int middle = low + (high - low) / 2;
1210 if (cp[middle] >= x1)
1211 best = high = middle;
1216 while (best > 0 && cp[best - 1] == cp[best])
1222 /* Renders the cells of PAGE that intersect (X,Y)-(X+W,Y+H), by calling the
1223 'draw_line' and 'draw_cell' functions from the render_params provided to
1224 render_page_create(). */
1226 render_page_draw_region (const struct render_page *page,
1227 int ofs[TABLE_N_AXES], int clip[TABLE_N_AXES][2])
1229 int bb[TABLE_N_AXES][2];
1231 bb[H][0] = get_clip_min_extent (clip[H][0], page->cp[H], page->n[H] * 2 + 1);
1232 bb[H][1] = get_clip_max_extent (clip[H][1], page->cp[H], page->n[H] * 2 + 1);
1233 bb[V][0] = get_clip_min_extent (clip[V][0], page->cp[V], page->n[V] * 2 + 1);
1234 bb[V][1] = get_clip_max_extent (clip[V][1], page->cp[V], page->n[V] * 2 + 1);
1236 render_page_draw_cells (page, ofs, bb);
1239 /* Breaking up tables to fit on a page. */
1241 /* An iterator for breaking render_pages into smaller chunks. */
1244 struct render_page *page; /* Page being broken up. */
1245 enum table_axis axis; /* Axis along which 'page' is being broken. */
1246 int z; /* Next cell along 'axis'. */
1247 int pixel; /* Pixel offset within cell 'z' (usually 0). */
1248 int hw; /* Width of headers of 'page' along 'axis'. */
1251 static int needed_size (const struct render_break *, int cell);
1252 static bool cell_is_breakable (const struct render_break *, int cell);
1253 static struct render_page *render_page_select (const struct render_page *,
1258 /* Initializes render_break B for breaking PAGE along AXIS.
1259 Takes ownership of PAGE. */
1261 render_break_init (struct render_break *b, struct render_page *page,
1262 enum table_axis axis)
1266 b->z = page->h[axis][0];
1268 b->hw = headers_width (page, axis);
1271 /* Initializes B as a render_break structure for which
1272 render_break_has_next() always returns false. */
1274 render_break_init_empty (struct render_break *b)
1277 b->axis = TABLE_HORZ;
1283 /* Frees B and unrefs the render_page that it owns. */
1285 render_break_destroy (struct render_break *b)
1289 render_page_unref (b->page);
1294 /* Returns true if B still has cells that are yet to be returned,
1295 false if all of B's page has been processed. */
1297 render_break_has_next (const struct render_break *b)
1299 const struct render_page *page = b->page;
1300 enum table_axis axis = b->axis;
1302 return page != NULL && b->z < page->n[axis] - page->h[axis][1];
1305 /* Returns a new render_page that is up to SIZE pixels wide along B's axis.
1306 Returns a null pointer if B has already been completely broken up, or if
1307 SIZE is too small to reasonably render any cells. The latter will never
1308 happen if SIZE is at least as large as the page size passed to
1309 render_page_create() along B's axis. */
1310 static struct render_page *
1311 render_break_next (struct render_break *b, int size)
1313 const struct render_page *page = b->page;
1314 enum table_axis axis = b->axis;
1315 struct render_page *subpage;
1317 if (!render_break_has_next (b))
1322 for (z = b->z; z < page->n[axis] - page->h[axis][1]; z++)
1324 int needed = needed_size (b, z + 1);
1327 if (cell_is_breakable (b, z))
1329 /* If there is no right header and we render a partial cell on
1330 the right side of the body, then we omit the rightmost rule of
1331 the body. Otherwise the rendering is deceptive because it
1332 looks like the whole cell is present instead of a partial
1335 This is similar to code for the left side in needed_size(). */
1336 int rule_allowance = (page->h[axis][1]
1338 : rule_width (page, axis, z));
1340 /* The amount that, if we added cell 'z', the rendering would
1341 overfill the allocated 'size'. */
1342 int overhang = needed - size - rule_allowance;
1344 /* The width of cell 'z'. */
1345 int cell_size = cell_width (page, axis, z);
1347 /* The amount trimmed off the left side of 'z',
1348 and the amount left to render. */
1349 int cell_ofs = z == b->z ? b->pixel : 0;
1350 int cell_left = cell_size - cell_ofs;
1352 /* A small but visible width. */
1353 int em = page->params->font_size[axis];
1355 /* If some of the cell remains to render,
1356 and there would still be some of the cell left afterward,
1357 then partially render that much of the cell. */
1358 pixel = (cell_left && cell_left > overhang
1359 ? cell_left - overhang + cell_ofs
1362 /* If there would be only a tiny amount of the cell left after
1363 rendering it partially, reduce the amount rendered slightly
1364 to make the output look a little better. */
1365 if (pixel + em > cell_size)
1366 pixel = MAX (pixel - em, 0);
1368 /* If we're breaking vertically, then consider whether the cells
1369 being broken have a better internal breakpoint than the exact
1370 number of pixels available, which might look bad e.g. because
1371 it breaks in the middle of a line of text. */
1372 if (axis == TABLE_VERT && page->params->adjust_break)
1373 for (int x = 0; x < page->n[H];)
1375 struct table_cell cell;
1377 render_get_cell (page, x, z, &cell);
1378 int w = joined_width (page, H, cell.d[H][0], cell.d[H][1]);
1379 int better_pixel = page->params->adjust_break (
1380 page->params->aux, &cell, w, pixel);
1383 if (better_pixel < pixel)
1385 if (better_pixel > (z == b->z ? b->pixel : 0))
1387 pixel = better_pixel;
1390 else if (better_pixel == 0 && z != b->z)
1402 if (z == b->z && !pixel)
1405 subpage = render_page_select (page, axis, b->z, b->pixel,
1407 pixel ? cell_width (page, axis, z) - pixel
1414 /* Returns the width that would be required along B's axis to render a page
1415 from B's current position up to but not including CELL. */
1417 needed_size (const struct render_break *b, int cell)
1419 const struct render_page *page = b->page;
1420 enum table_axis axis = b->axis;
1422 /* Width of left header not including its rightmost rule. */
1423 int size = axis_width (page, axis, 0, rule_ofs (page->h[axis][0]));
1425 /* If we have a pixel offset and there is no left header, then we omit the
1426 leftmost rule of the body. Otherwise the rendering is deceptive because
1427 it looks like the whole cell is present instead of a partial cell.
1429 Otherwise (if there are headers) we will be merging two rules: the
1430 rightmost rule in the header and the leftmost rule in the body. We assume
1431 that the width of a merged rule is the larger of the widths of either rule
1433 if (b->pixel == 0 || page->h[axis][0])
1434 size += MAX (rule_width (page, axis, page->h[axis][0]),
1435 rule_width (page, axis, b->z));
1437 /* Width of body, minus any pixel offset in the leftmost cell. */
1438 size += joined_width (page, axis, b->z, cell) - b->pixel;
1440 /* Width of rightmost rule in body merged with leftmost rule in headers. */
1441 size += MAX (rule_width_r (page, axis, page->h[axis][1]),
1442 rule_width (page, axis, cell));
1444 /* Width of right header not including its leftmost rule. */
1445 size += axis_width (page, axis, rule_ofs_r (page, axis, page->h[axis][1]),
1446 rule_ofs_r (page, axis, 0));
1448 /* Join crossing. */
1449 if (page->h[axis][0] && page->h[axis][1])
1450 size += page->join_crossing[axis][b->z];
1455 /* Returns true if CELL along B's axis may be broken across a page boundary.
1457 This is just a heuristic. Breaking cells across page boundaries can save
1458 space, but it looks ugly. */
1460 cell_is_breakable (const struct render_break *b, int cell)
1462 const struct render_page *page = b->page;
1463 enum table_axis axis = b->axis;
1465 return cell_width (page, axis, cell) >= page->params->min_break[axis];
1472 const struct render_params *params;
1474 struct render_page **pages;
1475 size_t n_pages, allocated_pages;
1478 struct render_break x_break;
1479 struct render_break y_break;
1482 static const struct render_page *
1483 render_pager_add_table (struct render_pager *p, struct table *table,
1486 if (p->n_pages >= p->allocated_pages)
1487 p->pages = x2nrealloc (p->pages, &p->allocated_pages, sizeof *p->pages);
1489 struct render_page *page = render_page_create (p->params, table, min_width);
1490 p->pages[p->n_pages++] = page;
1495 render_pager_start_page (struct render_pager *p)
1497 render_break_init (&p->x_break, render_page_ref (p->pages[p->cur_page++]),
1499 render_break_init_empty (&p->y_break);
1503 add_footnote_page (struct render_pager *p, const struct table_item *item)
1505 const struct footnote **f;
1506 size_t n_footnotes = table_collect_footnotes (item, &f);
1510 struct table *t = table_create (1, n_footnotes, 0, 0, 0, 0);
1512 for (size_t i = 0; i < n_footnotes; i++)
1514 table_text_format (t, 0, i, 0, "%s. %s", f[i]->marker, f[i]->content);
1515 table_add_style (t, 0, i, f[i]->style);
1517 render_pager_add_table (p, t, 0);
1523 add_text_page (struct render_pager *p, const struct table_item_text *t,
1529 struct table *tab = table_create (1, 1, 0, 0, 0, 0);
1530 table_text (tab, 0, 0, 0, t->content);
1531 for (size_t i = 0; i < t->n_footnotes; i++)
1532 table_add_footnote (tab, 0, 0, t->footnotes[i]);
1534 tab->styles[0] = area_style_clone (tab->container, t->style);
1535 render_pager_add_table (p, tab, min_width);
1539 add_layers_page (struct render_pager *p,
1540 const struct table_item_layers *layers, int min_width)
1545 struct table *tab = table_create (1, layers->n_layers, 0, 0, 0, 0);
1546 for (size_t i = 0; i < layers->n_layers; i++)
1548 const struct table_item_layer *layer = &layers->layers[i];
1549 table_text (tab, 0, i, 0, layer->content);
1550 for (size_t j = 0; j < layer->n_footnotes; j++)
1551 table_add_footnote (tab, 0, i, layer->footnotes[j]);
1554 tab->styles[0] = area_style_clone (tab->container, layers->style);
1555 render_pager_add_table (p, tab, min_width);
1558 /* Creates and returns a new render_pager for rendering TABLE_ITEM on the
1559 device with the given PARAMS. */
1560 struct render_pager *
1561 render_pager_create (const struct render_params *params,
1562 const struct table_item *table_item)
1564 const struct table *table = table_item_get_table (table_item);
1566 struct render_pager *p = xzalloc (sizeof *p);
1569 struct render_page *page = render_page_create (params, table_ref (table), 0);
1570 struct render_break b;
1571 render_break_init (&b, page, H);
1572 struct render_page *subpage = render_break_next (&b, p->params->size[H]);
1573 int title_width = subpage ? subpage->cp[H][2 * subpage->n[H] + 1] : 0;
1574 render_page_unref (subpage);
1575 render_break_destroy (&b);
1578 add_text_page (p, table_item_get_title (table_item), title_width);
1581 add_layers_page (p, table_item_get_layers (table_item), title_width);
1584 render_pager_add_table (p, table_ref (table_item_get_table (table_item)), 0);
1587 add_text_page (p, table_item_get_caption (table_item), 0);
1590 add_footnote_page (p, table_item);
1592 render_pager_start_page (p);
1599 render_pager_destroy (struct render_pager *p)
1603 render_break_destroy (&p->x_break);
1604 render_break_destroy (&p->y_break);
1605 for (size_t i = 0; i < p->n_pages; i++)
1606 render_page_unref (p->pages[i]);
1612 /* Returns true if P has content remaining to render, false if rendering is
1615 render_pager_has_next (const struct render_pager *p_)
1617 struct render_pager *p = CONST_CAST (struct render_pager *, p_);
1619 while (!render_break_has_next (&p->y_break))
1621 render_break_destroy (&p->y_break);
1622 if (!render_break_has_next (&p->x_break))
1624 render_break_destroy (&p->x_break);
1625 if (p->cur_page >= p->n_pages)
1627 render_break_init_empty (&p->x_break);
1628 render_break_init_empty (&p->y_break);
1631 render_pager_start_page (p);
1635 &p->y_break, render_break_next (&p->x_break, p->params->size[H]), V);
1640 /* Draws a chunk of content from P to fit in a space that has vertical size
1641 SPACE and the horizontal size specified in the render_params passed to
1642 render_page_create(). Returns the amount of space actually used by the
1643 rendered chunk, which will be 0 if SPACE is too small to render anything or
1644 if no content remains (use render_pager_has_next() to distinguish these
1647 render_pager_draw_next (struct render_pager *p, int space)
1649 int ofs[TABLE_N_AXES] = { 0, 0 };
1650 size_t start_page = SIZE_MAX;
1652 while (render_pager_has_next (p))
1654 if (start_page == p->cur_page)
1656 start_page = p->cur_page;
1658 struct render_page *page
1659 = render_break_next (&p->y_break, space - ofs[V]);
1663 render_page_draw (page, ofs);
1664 ofs[V] += render_page_get_size (page, V);
1665 render_page_unref (page);
1670 /* Draws all of P's content. */
1672 render_pager_draw (const struct render_pager *p)
1674 render_pager_draw_region (p, 0, 0, INT_MAX, INT_MAX);
1677 /* Draws the region of P's content that lies in the region (X,Y)-(X+W,Y+H).
1678 Some extra content might be drawn; the device should perform clipping as
1681 render_pager_draw_region (const struct render_pager *p,
1682 int x, int y, int w, int h)
1684 int ofs[TABLE_N_AXES] = { 0, 0 };
1685 int clip[TABLE_N_AXES][2];
1689 for (size_t i = 0; i < p->n_pages; i++)
1691 const struct render_page *page = p->pages[i];
1692 int size = render_page_get_size (page, V);
1694 clip[V][0] = MAX (y, ofs[V]) - ofs[V];
1695 clip[V][1] = MIN (y + h, ofs[V] + size) - ofs[V];
1696 if (clip[V][1] > clip[V][0])
1697 render_page_draw_region (page, ofs, clip);
1703 /* Returns the size of P's content along AXIS; i.e. the content's width if AXIS
1704 is TABLE_HORZ and its length if AXIS is TABLE_VERT. */
1706 render_pager_get_size (const struct render_pager *p, enum table_axis axis)
1710 for (size_t i = 0; i < p->n_pages; i++)
1712 int subsize = render_page_get_size (p->pages[i], axis);
1713 size = axis == H ? MAX (size, subsize) : size + subsize;
1720 render_pager_get_best_breakpoint (const struct render_pager *p, int height)
1725 for (i = 0; i < p->n_pages; i++)
1727 int size = render_page_get_size (p->pages[i], V);
1728 if (y + size >= height)
1729 return render_page_get_best_breakpoint (p->pages[i], height - y) + y;
1736 /* render_page_select() and helpers. */
1738 struct render_page_selection
1740 const struct render_page *page; /* Page whose slice we are selecting. */
1741 struct render_page *subpage; /* New page under construction. */
1742 enum table_axis a; /* Axis of 'page' along which 'subpage' is a slice. */
1743 enum table_axis b; /* The opposite of 'a'. */
1744 int z0; /* First cell along 'a' being selected. */
1745 int z1; /* Last cell being selected, plus 1. */
1746 int p0; /* Number of pixels to trim off left side of z0. */
1747 int p1; /* Number of pixels to trim off right side of z1-1. */
1750 static void cell_to_subpage (struct render_page_selection *,
1751 const struct table_cell *,
1752 int subcell[TABLE_N_AXES]);
1753 static const struct render_overflow *find_overflow_for_cell (
1754 struct render_page_selection *, const struct table_cell *);
1755 static struct render_overflow *insert_overflow (struct render_page_selection *,
1756 const struct table_cell *);
1758 /* Creates and returns a new render_page whose contents are a subregion of
1759 PAGE's contents. The new render_page includes cells Z0 through Z1
1760 (exclusive) along AXIS, plus any headers on AXIS.
1762 If P0 is nonzero, then it is a number of pixels to exclude from the left or
1763 top (according to AXIS) of cell Z0. Similarly, P1 is a number of pixels to
1764 exclude from the right or bottom of cell Z1 - 1. (P0 and P1 are used to
1765 render cells that are too large to fit on a single page.)
1767 The whole of axis !AXIS is included. (The caller may follow up with another
1768 call to render_page_select() to select on !AXIS to select on that axis as
1771 The caller retains ownership of PAGE, which is not modified. */
1772 static struct render_page *
1773 render_page_select (const struct render_page *page, enum table_axis axis,
1774 int z0, int p0, int z1, int p1)
1776 enum table_axis a = axis;
1777 enum table_axis b = !a;
1779 /* Optimize case where all of PAGE is selected by just incrementing the
1781 if (z0 == page->h[a][0] && p0 == 0
1782 && z1 == page->n[a] - page->h[a][1] && p1 == 0)
1784 struct render_page *page_rw = CONST_CAST (struct render_page *, page);
1789 /* Allocate subpage. */
1790 int trim[2] = { z0 - page->h[a][0], (page->n[a] - page->h[a][1]) - z1 };
1791 int n[TABLE_N_AXES] = { [H] = page->n[H], [V] = page->n[V] };
1792 n[a] -= trim[0] + trim[1];
1793 struct render_page *subpage = render_page_allocate__ (
1794 page->params, table_ref (page->table), n);
1795 for (enum table_axis k = 0; k < TABLE_N_AXES; k++)
1797 subpage->h[k][0] = page->h[k][0];
1798 subpage->h[k][1] = page->h[k][1];
1799 subpage->r[k][0] = page->r[k][0];
1800 subpage->r[k][1] = page->r[k][1];
1802 subpage->r[a][0] += trim[0];
1803 subpage->r[a][1] -= trim[1];
1805 /* An edge is cut off if it was cut off in PAGE or if we're trimming pixels
1806 off that side of the page and there are no headers. */
1807 subpage->is_edge_cutoff[a][0] =
1808 subpage->h[a][0] == 0 && (p0 || (z0 == 0 && page->is_edge_cutoff[a][0]));
1809 subpage->is_edge_cutoff[a][1] =
1810 subpage->h[a][1] == 0 && (p1 || (z1 == page->n[a]
1811 && page->is_edge_cutoff[a][1]));
1812 subpage->is_edge_cutoff[b][0] = page->is_edge_cutoff[b][0];
1813 subpage->is_edge_cutoff[b][1] = page->is_edge_cutoff[b][1];
1815 /* Select join crossings from PAGE into subpage. */
1816 int *jc = subpage->join_crossing[a];
1817 for (int z = 0; z < page->h[a][0]; z++)
1818 *jc++ = page->join_crossing[a][z];
1819 for (int z = z0; z <= z1; z++)
1820 *jc++ = page->join_crossing[a][z];
1821 for (int z = page->n[a] - page->h[a][1]; z < page->n[a]; z++)
1822 *jc++ = page->join_crossing[a][z];
1823 assert (jc == &subpage->join_crossing[a][subpage->n[a] + 1]);
1825 memcpy (subpage->join_crossing[b], page->join_crossing[b],
1826 (subpage->n[b] + 1) * sizeof **subpage->join_crossing);
1828 /* Select widths from PAGE into subpage. */
1829 int *scp = page->cp[a];
1830 int *dcp = subpage->cp[a];
1832 for (int z = 0; z <= rule_ofs (subpage->h[a][0]); z++, dcp++)
1834 int w = !z && subpage->is_edge_cutoff[a][0] ? 0 : scp[z + 1] - scp[z];
1835 dcp[1] = dcp[0] + w;
1837 for (int z = cell_ofs (z0); z <= cell_ofs (z1 - 1); z++, dcp++)
1839 dcp[1] = dcp[0] + (scp[z + 1] - scp[z]);
1840 if (z == cell_ofs (z0))
1843 if (page->h[a][0] && page->h[a][1])
1844 dcp[1] += page->join_crossing[a][z / 2];
1846 if (z == cell_ofs (z1 - 1))
1849 for (int z = rule_ofs_r (page, a, subpage->h[a][1]);
1850 z <= rule_ofs_r (page, a, 0); z++, dcp++)
1852 if (z == rule_ofs_r (page, a, 0) && subpage->is_edge_cutoff[a][1])
1855 dcp[1] = dcp[0] + (scp[z + 1] - scp[z]);
1857 assert (dcp == &subpage->cp[a][2 * subpage->n[a] + 1]);
1859 for (int z = 0; z < page->n[b] * 2 + 2; z++)
1860 subpage->cp[b][z] = page->cp[b][z];
1862 /* Add new overflows. */
1863 struct render_page_selection s = {
1874 if (!page->h[a][0] || z0 > page->h[a][0] || p0)
1875 for (int z = 0; z < page->n[b];)
1877 int d[TABLE_N_AXES];
1881 struct table_cell cell;
1882 render_get_cell (page, d[H], d[V], &cell);
1883 bool overflow0 = p0 || cell.d[a][0] < z0;
1884 bool overflow1 = cell.d[a][1] > z1 || (cell.d[a][1] == z1 && p1);
1885 if (overflow0 || overflow1)
1887 struct render_overflow *ro = insert_overflow (&s, &cell);
1891 ro->overflow[a][0] += p0 + axis_width (
1892 page, a, cell_ofs (cell.d[a][0]), cell_ofs (z0));
1893 if (page->h[a][0] && page->h[a][1])
1894 ro->overflow[a][0] -= page->join_crossing[a][cell.d[a][0]
1900 ro->overflow[a][1] += p1 + axis_width (
1901 page, a, cell_ofs (z1), cell_ofs (cell.d[a][1]));
1902 if (page->h[a][0] && page->h[a][1])
1903 ro->overflow[a][1] -= page->join_crossing[a][cell.d[a][1]];
1909 if (!page->h[a][1] || z1 < page->n[a] - page->h[a][1] || p1)
1910 for (int z = 0; z < page->n[b];)
1912 int d[TABLE_N_AXES];
1916 struct table_cell cell;
1917 render_get_cell (page, d[H], d[V], &cell);
1918 if ((cell.d[a][1] > z1 || (cell.d[a][1] == z1 && p1))
1919 && find_overflow_for_cell (&s, &cell) == NULL)
1921 struct render_overflow *ro = insert_overflow (&s, &cell);
1922 ro->overflow[a][1] += p1 + axis_width (page, a, cell_ofs (z1),
1923 cell_ofs (cell.d[a][1]));
1928 /* Copy overflows from PAGE into subpage. */
1929 struct render_overflow *ro;
1930 HMAP_FOR_EACH (ro, struct render_overflow, node, &page->overflows)
1932 struct table_cell cell;
1934 table_get_cell (page->table, ro->d[H], ro->d[V], &cell);
1935 if (cell.d[a][1] > z0 && cell.d[a][0] < z1
1936 && find_overflow_for_cell (&s, &cell) == NULL)
1937 insert_overflow (&s, &cell);
1943 /* Given CELL, a table_cell within S->page, stores in SUBCELL the (x,y)
1944 coordinates of the top-left cell as it will appear in S->subpage.
1946 CELL must actually intersect the region of S->page that is being selected
1947 by render_page_select() or the results will not make any sense. */
1949 cell_to_subpage (struct render_page_selection *s,
1950 const struct table_cell *cell, int subcell[TABLE_N_AXES])
1952 enum table_axis a = s->a;
1953 enum table_axis b = s->b;
1954 int ha0 = s->subpage->h[a][0];
1956 subcell[a] = MAX (cell->d[a][0] - s->z0 + ha0, ha0);
1957 subcell[b] = cell->d[b][0];
1960 /* Given CELL, a table_cell within S->page, returns the render_overflow for
1961 that cell in S->subpage, if there is one, and a null pointer otherwise.
1963 CELL must actually intersect the region of S->page that is being selected
1964 by render_page_select() or the results will not make any sense. */
1965 static const struct render_overflow *
1966 find_overflow_for_cell (struct render_page_selection *s,
1967 const struct table_cell *cell)
1971 cell_to_subpage (s, cell, subcell);
1972 return find_overflow (s->subpage, subcell[H], subcell[V]);
1975 /* Given CELL, a table_cell within S->page, inserts a render_overflow for that
1976 cell in S->subpage (which must not already exist). Initializes the new
1977 render_overflow's 'overflow' member from the overflow for CELL in S->page,
1980 CELL must actually intersect the region of S->page that is being selected
1981 by render_page_select() or the results will not make any sense. */
1982 static struct render_overflow *
1983 insert_overflow (struct render_page_selection *s,
1984 const struct table_cell *cell)
1986 struct render_overflow *of = xzalloc (sizeof *of);
1987 cell_to_subpage (s, cell, of->d);
1988 hmap_insert (&s->subpage->overflows, &of->node,
1989 hash_cell (of->d[H], of->d[V]));
1991 const struct render_overflow *old
1992 = find_overflow (s->page, cell->d[H][0], cell->d[V][0]);
1994 memcpy (of->overflow, old->overflow, sizeof of->overflow);