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

   1 % pdfsaverestore.w
   2 %
   3 % Copyright 2010 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 pos_entry *pos_stack = 0; /* the stack */
  26 int pos_stack_size = 0;   /* initially empty */
  27 int pos_stack_used = 0;   /* used entries */
  28
  29 @ @c
  30 static void checkpdfsave(scaledpos pos)
  31 {
  32     pos_entry *new_stack;
  33     if (pos_stack_used >= pos_stack_size) {
  34         pos_stack_size += STACK_INCREMENT;
  35         new_stack = xtalloc((unsigned) pos_stack_size, pos_entry);
  36         memcpy((void *) new_stack, (void *) pos_stack, (unsigned) pos_stack_used * sizeof(pos_entry));
  37         xfree(pos_stack);
  38         pos_stack = new_stack;
  39     }
  40     pos_stack[pos_stack_used].pos.h = pos.h;
  41     pos_stack[pos_stack_used].pos.v = pos.v;
  42     if (global_shipping_mode == SHIPPING_PAGE) {
  43         pos_stack[pos_stack_used].matrix_stack = matrix_stack_used;
  44     }
  45     pos_stack_used++;
  46 }
  47
  48 @ @c
  49 static void checkpdfrestore(scaledpos pos)
  50 {
  51     scaledpos diff;
  52     if (pos_stack_used == 0) {
  53         normal_warning("pdf backend", "'restore' is missing a 'save'");
  54         return;
  55     }
  56     pos_stack_used--;
  57     diff.h = pos.h - pos_stack[pos_stack_used].pos.h;
  58     diff.v = pos.v - pos_stack[pos_stack_used].pos.v;
  59     if (diff.h != 0 || diff.v != 0) {
  60         formatted_warning("pdf backend","misplaced 'restore' by (%dsp, %dsp)", (int) diff.h, (int) diff.v);
  61     }
  62     if (global_shipping_mode == SHIPPING_PAGE) {
  63         matrix_stack_used = pos_stack[pos_stack_used].matrix_stack;
  64     }
  65 }
  66
  67 @ @c
  68 void pdf_out_save(PDF pdf, halfword p)
  69 {
  70     (void) p;
  71     checkpdfsave(pdf->posstruct->pos);
  72     pdf_literal(pdf, 'q', set_origin, false);
  73 }
  74
  75 @ @c
  76 void pdf_out_restore(PDF pdf, halfword p)
  77 {
  78     (void) p;
  79     checkpdfrestore(pdf->posstruct->pos);
  80     pdf_literal(pdf, 'Q', set_origin, false);
  81 }