source/texk/web2c/luatexdir/pdf/pdfthread.w

   1 % pdfthread.w
   2 %
   3 % Copyright 2009-2012 Taco Hoekwater <taco@@luatex.org>
   4 %
   5 % This file is part of LuaTeX.
   6 %
   7 % LuaTeX is free software; you can redistribute it and/or modify it under
   8 % the terms of the GNU General Public License as published by the Free
   9 % Software Foundation; either version 2 of the License, or (at your
  10 % option) any later version.
  11 %
  12 % LuaTeX is distributed in the hope that it will be useful, but WITHOUT
  13 % ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 % FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  15 % License for more details.
  16 %
  17 % You should have received a copy of the GNU General Public License along
  18 % with LuaTeX; if not, see <http://www.gnu.org/licenses/>.
  19
  20 @ @c
  21
  22 #include "ptexlib.h"
  23
  24 @ @c
  25 #define page_width dimen_par(page_width_code)
  26 #define page_height dimen_par(page_height_code)
  27
  28 @ Threads are handled in similar way as link annotations
  29 @c
  30 void append_bead(PDF pdf, halfword p)
  31 {
  32     int a, b, c, t;
  33     if (global_shipping_mode == SHIPPING_FORM)
  34         normal_error("pdf backend", "threads cannot be inside an xform");
  35     t = pdf_get_obj(pdf, obj_type_thread, pdf_thread_id(p), pdf_thread_named_id(p));
  36     b = pdf_create_obj(pdf, obj_type_others, 0);
  37     obj_bead_ptr(pdf, b) = pdf_get_mem(pdf, pdfmem_bead_size);
  38     set_obj_bead_page(pdf, b, pdf->last_page);
  39     set_obj_bead_data(pdf, b, p);
  40     if (pdf_thread_attr(p) != null)
  41         set_obj_bead_attr(pdf, b, tokens_to_string(pdf_thread_attr(p)));
  42     else
  43         set_obj_bead_attr(pdf, b, 0);
  44     if (obj_thread_first(pdf, t) == 0) {
  45         obj_thread_first(pdf, t) = b;
  46         set_obj_bead_next(pdf, b, b);
  47         set_obj_bead_prev(pdf, b, b);
  48     } else {
  49         a = obj_thread_first(pdf, t);
  50         c = obj_bead_prev(pdf, a);
  51         set_obj_bead_prev(pdf, b, c);
  52         set_obj_bead_next(pdf, b, a);
  53         set_obj_bead_prev(pdf, a, b);
  54         set_obj_bead_next(pdf, c, b);
  55     }
  56     addto_page_resources(pdf, obj_type_bead, b);
  57 }
  58
  59 @ @c
  60 void do_thread(PDF pdf, halfword p, halfword parent_box, scaledpos cur)
  61 {
  62     scaled_whd alt_rule;
  63     if ((type(p) == hlist_node) && (subtype(p) == pdf_start_thread_node))
  64         normal_error("pdf backend", "'startthread' ended up in hlist");
  65     if (doing_leaders)
  66         return;
  67     if (subtype(p) == pdf_start_thread_node) {
  68         pdf->thread.wd = width(p);
  69         pdf->thread.ht = height(p);
  70         pdf->thread.dp = depth(p);
  71         pdf->last_thread_id = pdf_thread_id(p);
  72         pdf->last_thread_named_id = (pdf_thread_named_id(p) > 0);
  73         if (pdf->last_thread_named_id)
  74             add_token_ref(pdf_thread_id(p));
  75         pdf->thread_level = cur_s;
  76     }
  77     alt_rule.wd = width(p);
  78     alt_rule.ht = height(p);
  79     alt_rule.dp = depth(p);
  80     set_rect_dimens(pdf, p, parent_box, cur, alt_rule, pdf_thread_margin);
  81     append_bead(pdf, p);
  82     pdf->last_thread = p;
  83 }
  84
  85 @ @c
  86 void append_thread(PDF pdf, halfword parent_box, scaledpos cur)
  87 {
  88     scaled_whd alt_rule;
  89     halfword p = new_node(whatsit_node, pdf_thread_data_node);
  90     width(p) = pdf->thread.wd;
  91     height(p) = pdf->thread.ht;
  92     depth(p) = pdf->thread.dp;
  93     pdf_thread_attr(p) = null;
  94     pdf_thread_id(p) = pdf->last_thread_id;
  95     if (pdf->last_thread_named_id) {
  96         add_token_ref(pdf_thread_id(p));
  97         pdf_thread_named_id(p) = 1;
  98     } else {
  99         pdf_thread_named_id(p) = 0;
 100     }
 101     alt_rule.wd = width(p);
 102     alt_rule.ht = height(p);
 103     alt_rule.dp = depth(p);
 104     set_rect_dimens(pdf, p, parent_box, cur, alt_rule, pdf_thread_margin);
 105     append_bead(pdf, p);
 106     pdf->last_thread = p;
 107 }
 108
 109 @ @c
 110 void end_thread(PDF pdf, halfword p)
 111 {
 112     scaledpos pos = pdf->posstruct->pos;
 113     if (type(p) == hlist_node)
 114         normal_error("pdf backend", "'endthread' ended up in hlist");
 115     if (pdf->thread_level != cur_s)
 116         normal_error("pdf backend", "'endthread' ended up in different nesting level than 'startthread'");
 117     if (is_running(pdf->thread.dp) && (pdf->last_thread != null)) {
 118         switch (pdf->posstruct->dir) {
 119             case dir_TLT:
 120             case dir_TRT:
 121                 pdf_ann_bottom(pdf->last_thread) = pos.v - pdf_thread_margin;
 122                 break;
 123             case dir_LTL:
 124                 pdf_ann_right(pdf->last_thread) = pos.h + pdf_thread_margin;
 125                 break;
 126             case dir_RTT:
 127                 pdf_ann_left(pdf->last_thread) = pos.h - pdf_thread_margin;
 128                 break;
 129             default:
 130                 formatted_warning("pdf backend","forcing bad dir %i to TLT in end tread",pdf->posstruct->dir);
 131         }
 132     }
 133     if (pdf->last_thread_named_id)
 134         delete_token_ref(pdf->last_thread_id);
 135     pdf->last_thread = null;
 136 }
 137
 138 @ The following function are needed for outputing article thread.
 139 @c
 140 void thread_title(PDF pdf, int t)
 141 {
 142     pdf_add_name(pdf, "Title");
 143     pdf_out(pdf, '(');
 144     if (obj_info(pdf, t) < 0)
 145         pdf_print(pdf, -obj_info(pdf, t));
 146     else
 147         pdf_print_int(pdf, obj_info(pdf, t));
 148     pdf_out(pdf, ')');
 149 }
 150
 151 void pdf_fix_thread(PDF pdf, int t)
 152 {
 153     halfword a;
 154     if (obj_info(pdf, t) < 0) {
 155         char *ss = makecstring(-obj_info(pdf, t));
 156         formatted_warning("pdf backend", "unknown thread destination name '%s'",ss);
 157     } else {
 158         formatted_warning("pdf backend", "unknown thread destination num '%d'",obj_info(pdf, t));
 159     }
 160     a = pdf_create_obj(pdf, obj_type_others, 0);
 161     pdf_begin_obj(pdf, a, OBJSTM_ALWAYS);
 162     pdf_begin_dict(pdf);
 163     pdf_dict_add_ref(pdf, "T", t);
 164     pdf_dict_add_ref(pdf, "V", a);
 165     pdf_dict_add_ref(pdf, "N", a);
 166     pdf_dict_add_ref(pdf, "P", pdf->last_page);
 167     pdf_add_name(pdf, "R");
 168     pdf_begin_array(pdf);
 169     pdf_add_int(pdf, 0);
 170     pdf_add_int(pdf, 0);
 171     pdf_add_bp(pdf, page_width);
 172     pdf_add_bp(pdf, page_height);
 173     pdf_end_array(pdf);
 174     pdf_end_dict(pdf);
 175     pdf_end_obj(pdf);
 176     pdf_begin_obj(pdf, t, OBJSTM_ALWAYS);
 177     pdf_begin_dict(pdf);
 178     pdf_add_name(pdf, "I");
 179     pdf_begin_dict(pdf);
 180     thread_title(pdf, t);
 181     pdf_end_dict(pdf);
 182     pdf_dict_add_ref(pdf, "F", a);
 183     pdf_end_dict(pdf);
 184     pdf_end_obj(pdf);
 185 }
 186
 187 void out_thread(PDF pdf, int t)
 188 {
 189     halfword a, b;
 190     int last_attr;
 191     if (obj_thread_first(pdf, t) == 0) {
 192         pdf_fix_thread(pdf, t);
 193         return;
 194     }
 195     pdf_begin_obj(pdf, t, OBJSTM_ALWAYS);
 196     pdf_begin_dict(pdf);
 197     a = obj_thread_first(pdf, t);
 198     b = a;
 199     last_attr = 0;
 200     do {
 201         if (obj_bead_attr(pdf, a) != 0)
 202             last_attr = obj_bead_attr(pdf, a);
 203         a = obj_bead_next(pdf, a);
 204     } while (a != b);
 205     if (last_attr != 0) {
 206         pdf_print_ln(pdf, last_attr);
 207     } else {
 208         pdf_add_name(pdf, "I");
 209         pdf_begin_dict(pdf);
 210         thread_title(pdf, t);
 211         pdf_end_dict(pdf);
 212     }
 213     pdf_dict_add_ref(pdf, "F", a);
 214     pdf_end_dict(pdf);
 215     pdf_end_obj(pdf);
 216     do {
 217         pdf_begin_obj(pdf, a, OBJSTM_ALWAYS);
 218         pdf_begin_dict(pdf);
 219         if (a == b)
 220             pdf_dict_add_ref(pdf, "T", t);
 221         pdf_dict_add_ref(pdf, "V", obj_bead_prev(pdf, a));
 222         pdf_dict_add_ref(pdf, "N", obj_bead_next(pdf, a));
 223         pdf_dict_add_ref(pdf, "P", obj_bead_page(pdf, a));
 224         pdf_dict_add_ref(pdf, "R", obj_bead_rect(pdf, a));
 225         pdf_end_dict(pdf);
 226         pdf_end_obj(pdf);
 227         a = obj_bead_next(pdf, a);
 228     } while (a != b);
 229 }
 230
 231 @ @c
 232 void scan_thread_id(void)
 233 {
 234     if (scan_keyword("num")) {
 235         scan_int();
 236         if (cur_val <= 0)
 237             normal_error("pdf backend", "num identifier must be positive");
 238         if (cur_val > max_halfword)
 239             normal_error("pdf backend", "number too big");
 240         set_pdf_thread_id(cur_list.tail_field, cur_val);
 241         set_pdf_thread_named_id(cur_list.tail_field, 0);
 242     } else if (scan_keyword("name")) {
 243         scan_toks(false, true);
 244         set_pdf_thread_id(cur_list.tail_field, def_ref);
 245         set_pdf_thread_named_id(cur_list.tail_field, 1);
 246     } else {
 247         normal_error("pdf backend", "identifier type missing");
 248     }
 249 }
 250
 251 void check_running_thread(PDF pdf, halfword this_box, scaledpos cur)
 252 {
 253     if ((pdf->last_thread != null) && is_running(pdf->thread.dp)
 254         && (pdf->thread_level == cur_s))
 255         append_thread(pdf, this_box, cur);
 256 }
 257
 258 @ @c
 259 void print_bead_rectangles(PDF pdf)
 260 {
 261     halfword i;
 262     pdf_object_list *k;
 263     int l;
 264     if ((k = get_page_resources_list(pdf, obj_type_bead)) != NULL) {
 265         while (k != NULL) {
 266             l = pdf_create_obj(pdf, obj_type_others, 0);
 267             pdf_begin_obj(pdf, l, OBJSTM_ALWAYS);
 268             pdf_begin_array(pdf);
 269             i = obj_bead_data(pdf, k->info); /* pointer to a whatsit or whatsit-like node */
 270             pdf_add_rect_spec(pdf, i);
 271             if (subtype(i) == pdf_thread_data_node)
 272                 flush_node(i);
 273             pdf_end_array(pdf);
 274             pdf_end_obj(pdf);
 275             set_obj_bead_rect(pdf, k->info, l); /* rewrite |obj_bead_data| */
 276             k = k->link;
 277         }
 278     }
 279 }