src/pre-eqn/over.cpp

   1 /*@
   2  * Copyright (c) 2014 - 2017 Steffen (Daode) Nurpmeso <steffen@sdaoden.eu>.
   3  *
   4  * Copyright (C) 1989 - 1992, 2001, 2002, 2007
   5  *    Free Software Foundation, Inc.
   6  *      Written by James Clark (jjc@jclark.com)
   7  *
   8  * This is free software; you can redistribute it and/or modify it under
   9  * the terms of the GNU General Public License as published by the Free
  10  * Software Foundation; either version 2, or (at your option) any later
  11  * version.
  12  *
  13  * This is distributed in the hope that it will be useful, but WITHOUT ANY
  14  * WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16  * for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with groff; see the file COPYING.  If not, write to the Free Software
  20  * Foundation, 51 Franklin St - Fifth Floor, Boston, MA 02110-1301, USA.
  21  */
  22
  23 #include "config.h"
  24 #include "eqn-config.h"
  25
  26 #include "eqn.h"
  27 #include "pbox.h"
  28
  29 class over_box
  30 : public box
  31 {
  32   int reduce_size;
  33   box *num;
  34   box *den;
  35
  36 public:
  37   over_box(int small, box *, box *);
  38   ~over_box();
  39   void debug_print();
  40   int compute_metrics(int);
  41   void output();
  42   void check_tabs(int);
  43 };
  44
  45 box *make_over_box(box *pp, box *qq)
  46 {
  47   return new over_box(0, pp, qq);
  48 }
  49
  50 box *make_small_over_box(box *pp, box *qq)
  51 {
  52   return new over_box(1, pp, qq);
  53 }
  54
  55 over_box::over_box(int is_small, box *pp, box *qq)
  56 : reduce_size(is_small), num(pp), den(qq)
  57 {
  58   spacing_type = INNER_TYPE;
  59 }
  60
  61 over_box::~over_box()
  62 {
  63   delete num;
  64   delete den;
  65 }
  66
  67 int over_box::compute_metrics(int style)
  68 {
  69   if (reduce_size) {
  70     style = script_style(style);
  71     printf(".nr " SIZE_FORMAT " \\n[.ps]\n", uid);
  72     set_script_size();
  73     printf(".nr " SMALL_SIZE_FORMAT " \\n[.ps]\n", uid);
  74   }
  75   int mark_uid = 0;
  76   int res = num->compute_metrics(style);
  77   if (res)
  78     mark_uid = num->uid;
  79   int r = den->compute_metrics(cramped_style(style));
  80   if (r && res)
  81     error("multiple marks and lineups");
  82   else {
  83     mark_uid = den->uid;
  84     res = r;
  85   }
  86   if (reduce_size)
  87     printf(".ps \\n[" SIZE_FORMAT "]u\n", uid);
  88   printf(".nr " WIDTH_FORMAT " (\\n[" WIDTH_FORMAT "]>?\\n[" WIDTH_FORMAT "]",
  89          uid, num->uid, den->uid);
  90   // allow for \(ru being wider than both the numerator and denominator
  91   if (!draw_flag)
  92     fputs(">?\\w" DELIMITER_CHAR "\\(ru" DELIMITER_CHAR, stdout);
  93   printf(")+%dM\n", null_delimiter_space*2 + over_hang*2);
  94   // 15b
  95   printf(".nr " SUP_RAISE_FORMAT " %dM\n",
  96          uid, (reduce_size ? num2 : num1));
  97   printf(".nr " SUB_LOWER_FORMAT " %dM\n",
  98          uid, (reduce_size ? denom2 : denom1));
  99
 100   // 15d
 101   printf(".nr " SUP_RAISE_FORMAT " +(\\n[" DEPTH_FORMAT
 102          "]-\\n[" SUP_RAISE_FORMAT "]+%dM+(%dM/2)+%dM)>?0\n",
 103          uid, num->uid, uid, axis_height, default_rule_thickness,
 104          default_rule_thickness*(reduce_size ? 1 : 3));
 105   printf(".nr " SUB_LOWER_FORMAT " +(\\n[" HEIGHT_FORMAT
 106          "]-\\n[" SUB_LOWER_FORMAT "]-%dM+(%dM/2)+%dM)>?0\n",
 107          uid, den->uid, uid, axis_height, default_rule_thickness,
 108          default_rule_thickness*(reduce_size ? 1 : 3));
 109
 110
 111   printf(".nr " HEIGHT_FORMAT " \\n[" SUP_RAISE_FORMAT "]+\\n["
 112          HEIGHT_FORMAT "]\n",
 113          uid, uid, num->uid);
 114   printf(".nr " DEPTH_FORMAT " \\n[" SUB_LOWER_FORMAT "]+\\n["
 115          DEPTH_FORMAT "]\n",
 116          uid, uid, den->uid);
 117   if (res)
 118     printf(".nr " MARK_REG " +(\\n[" WIDTH_FORMAT "]-\\n["
 119            WIDTH_FORMAT "]/2)\n", uid, mark_uid);
 120   return res;
 121 }
 122
 123 #define USE_Z
 124
 125 void over_box::output()
 126 {
 127   if (output_format == troff) {
 128     if (reduce_size)
 129       printf("\\s[\\n[" SMALL_SIZE_FORMAT "]u]", uid);
 130 #ifdef USE_Z
 131     printf("\\Z" DELIMITER_CHAR);
 132 #endif
 133     // move up to the numerator baseline
 134     printf("\\v'-\\n[" SUP_RAISE_FORMAT "]u'", uid);
 135     // move across so that it's centered
 136     printf("\\h'\\n[" WIDTH_FORMAT "]u-\\n[" WIDTH_FORMAT "]u/2u'",
 137            uid, num->uid);
 138
 139     // print the numerator
 140     num->output();
 141
 142 #ifdef USE_Z
 143     printf(DELIMITER_CHAR);
 144 #else
 145     // back again
 146     printf("\\h'-\\n[" WIDTH_FORMAT "]u'", num->uid);
 147     printf("\\h'-(\\n[" WIDTH_FORMAT "]u-\\n[" WIDTH_FORMAT "]u/2u)'",
 148            uid, num->uid);
 149     // down again
 150     printf("\\v'\\n[" SUP_RAISE_FORMAT "]u'", uid);
 151 #endif
 152 #ifdef USE_Z
 153     printf("\\Z" DELIMITER_CHAR);
 154 #endif
 155     // move down to the denominator baseline
 156     printf("\\v'\\n[" SUB_LOWER_FORMAT "]u'", uid);
 157
 158     // move across so that it's centered
 159     printf("\\h'\\n[" WIDTH_FORMAT "]u-\\n[" WIDTH_FORMAT "]u/2u'",
 160            uid, den->uid);
 161
 162     // print the the denominator
 163     den->output();
 164
 165 #ifdef USE_Z
 166     printf(DELIMITER_CHAR);
 167 #else
 168     // back again
 169     printf("\\h'-\\n[" WIDTH_FORMAT "]u'", den->uid);
 170     printf("\\h'-(\\n[" WIDTH_FORMAT "]u-\\n[" WIDTH_FORMAT "]u/2u)'",
 171            uid, den->uid);
 172     // up again
 173     printf("\\v'-\\n[" SUB_LOWER_FORMAT "]u'", uid);
 174 #endif
 175     if (reduce_size)
 176       printf("\\s[\\n[" SIZE_FORMAT "]u]", uid);
 177     // draw the line
 178     printf("\\h'%dM'", null_delimiter_space);
 179     printf("\\v'-%dM'", axis_height);
 180     fputs(draw_flag ? "\\D'l" : "\\l'", stdout);
 181     printf("\\n[" WIDTH_FORMAT "]u-%dM",
 182            uid, 2*null_delimiter_space);
 183     fputs(draw_flag ? " 0'" : "\\&\\(ru'", stdout);
 184     printf("\\v'%dM'", axis_height);
 185     printf("\\h'%dM'", null_delimiter_space);
 186   }
 187   else if (output_format == mathml) {
 188     // FIXME: passing a displaystyle attribute doesn't validate.
 189     printf("<mfrac>");
 190     num->output();
 191     den->output();
 192     printf("</mfrac>");
 193   }
 194 }
 195
 196 void over_box::debug_print()
 197 {
 198   fprintf(stderr, "{ ");
 199   num->debug_print();
 200   if (reduce_size)
 201     fprintf(stderr, " } smallover { ");
 202   else
 203     fprintf(stderr, " } over { ");
 204   den->debug_print();
 205   fprintf(stderr, " }");
 206 }
 207
 208 void over_box::check_tabs(int level)
 209 {
 210   num->check_tabs(level + 1);
 211   den->check_tabs(level + 1);
 212 }
 213
 214 // s-it2-mode