src/preproc/eqn/over.cpp

   1 // -*- C++ -*-
   2 /* Copyright (C) 1989, 1990, 1991, 1992, 2001, 2002
   3    Free Software Foundation, Inc.
   4      Written by James Clark (jjc@jclark.com)
   5
   6 This file is part of groff.
   7
   8 groff 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 groff 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 #include "eqn.h"
  23 #include "pbox.h"
  24
  25 class over_box : public box {
  26 private:
  27   int reduce_size;
  28   box *num;
  29   box *den;
  30 public:
  31   over_box(int small, box *, box *);
  32   ~over_box();
  33   void debug_print();
  34   int compute_metrics(int);
  35   void output();
  36   void check_tabs(int);
  37 };
  38
  39 box *make_over_box(box *pp, box *qq)
  40 {
  41   return new over_box(0, pp, qq);
  42 }
  43
  44 box *make_small_over_box(box *pp, box *qq)
  45 {
  46   return new over_box(1, pp, qq);
  47 }
  48
  49 over_box::over_box(int is_small, box *pp, box *qq)
  50 : reduce_size(is_small), num(pp), den(qq)
  51 {
  52   spacing_type = INNER_TYPE;
  53 }
  54
  55 over_box::~over_box()
  56 {
  57   delete num;
  58   delete den;
  59 }
  60
  61 int over_box::compute_metrics(int style)
  62 {
  63   if (reduce_size) {
  64     style = script_style(style);
  65     printf(".nr " SIZE_FORMAT " \\n[.ps]\n", uid);
  66     set_script_size();
  67     printf(".nr " SMALL_SIZE_FORMAT " \\n[.ps]\n", uid);
  68   }
  69   int mark_uid = 0;
  70   int res = num->compute_metrics(style);
  71   if (res)
  72     mark_uid = num->uid;
  73   int r = den->compute_metrics(cramped_style(style));
  74   if (r && res)
  75     error("multiple marks and lineups");
  76   else {
  77     mark_uid = den->uid;
  78     res = r;
  79   }
  80   if (reduce_size)
  81     printf(".ps \\n[" SIZE_FORMAT "]u\n", uid);
  82   printf(".nr " WIDTH_FORMAT " (\\n[" WIDTH_FORMAT "]>?\\n[" WIDTH_FORMAT "]",
  83          uid, num->uid, den->uid);
  84   // allow for \(ru being wider than both the numerator and denominator
  85   if (!draw_flag)
  86     fputs(">?\\w" DELIMITER_CHAR "\\(ru" DELIMITER_CHAR, stdout);
  87   printf(")+%dM\n", null_delimiter_space*2 + over_hang*2);
  88   // 15b
  89   printf(".nr " SUP_RAISE_FORMAT " %dM\n",
  90          uid, (reduce_size ? num2 : num1));
  91   printf(".nr " SUB_LOWER_FORMAT " %dM\n",
  92          uid, (reduce_size ? denom2 : denom1));
  93
  94   // 15d
  95   printf(".nr " SUP_RAISE_FORMAT " +(\\n[" DEPTH_FORMAT
  96          "]-\\n[" SUP_RAISE_FORMAT "]+%dM+(%dM/2)+%dM)>?0\n",
  97          uid, num->uid, uid, axis_height, default_rule_thickness,
  98          default_rule_thickness*(reduce_size ? 1 : 3));
  99   printf(".nr " SUB_LOWER_FORMAT " +(\\n[" HEIGHT_FORMAT
 100          "]-\\n[" SUB_LOWER_FORMAT "]-%dM+(%dM/2)+%dM)>?0\n",
 101          uid, den->uid, uid, axis_height, default_rule_thickness,
 102          default_rule_thickness*(reduce_size ? 1 : 3));
 103
 104
 105   printf(".nr " HEIGHT_FORMAT " \\n[" SUP_RAISE_FORMAT "]+\\n["
 106          HEIGHT_FORMAT "]\n",
 107          uid, uid, num->uid);
 108   printf(".nr " DEPTH_FORMAT " \\n[" SUB_LOWER_FORMAT "]+\\n["
 109          DEPTH_FORMAT "]\n",
 110          uid, uid, den->uid);
 111   if (res)
 112     printf(".nr " MARK_REG " +(\\n[" WIDTH_FORMAT "]-\\n["
 113            WIDTH_FORMAT "]/2)\n", uid, mark_uid);
 114   return res;
 115 }
 116
 117 #define USE_Z
 118
 119 void over_box::output()
 120 {
 121   if (reduce_size)
 122     printf("\\s[\\n[" SMALL_SIZE_FORMAT "]u]", uid);
 123 #ifdef USE_Z
 124   printf("\\Z" DELIMITER_CHAR);
 125 #endif
 126   // move up to the numerator baseline
 127   printf("\\v'-\\n[" SUP_RAISE_FORMAT "]u'", uid);
 128   // move across so that it's centered
 129   printf("\\h'\\n[" WIDTH_FORMAT "]u-\\n[" WIDTH_FORMAT "]u/2u'",
 130          uid, num->uid);
 131
 132   // print the numerator
 133   num->output();
 134
 135 #ifdef USE_Z
 136   printf(DELIMITER_CHAR);
 137 #else
 138   // back again
 139   printf("\\h'-\\n[" WIDTH_FORMAT "]u'", num->uid);
 140   printf("\\h'-(\\n[" WIDTH_FORMAT "]u-\\n[" WIDTH_FORMAT "]u/2u)'",
 141          uid, num->uid);
 142   // down again
 143   printf("\\v'\\n[" SUP_RAISE_FORMAT "]u'", uid);
 144 #endif
 145 #ifdef USE_Z
 146   printf("\\Z" DELIMITER_CHAR);
 147 #endif
 148   // move down to the denominator baseline
 149   printf("\\v'\\n[" SUB_LOWER_FORMAT "]u'", uid);
 150
 151   // move across so that it's centered
 152   printf("\\h'\\n[" WIDTH_FORMAT "]u-\\n[" WIDTH_FORMAT "]u/2u'",
 153          uid, den->uid);
 154
 155   // print the the denominator
 156   den->output();
 157
 158 #ifdef USE_Z
 159   printf(DELIMITER_CHAR);
 160 #else
 161   // back again
 162   printf("\\h'-\\n[" WIDTH_FORMAT "]u'", den->uid);
 163   printf("\\h'-(\\n[" WIDTH_FORMAT "]u-\\n[" WIDTH_FORMAT "]u/2u)'",
 164          uid, den->uid);
 165   // up again
 166   printf("\\v'-\\n[" SUB_LOWER_FORMAT "]u'", uid);
 167 #endif
 168   if (reduce_size)
 169     printf("\\s[\\n[" SIZE_FORMAT "]u]", uid);
 170   // draw the line
 171   printf("\\h'%dM'", null_delimiter_space);
 172   printf("\\v'-%dM'", axis_height);
 173   fputs(draw_flag ? "\\D'l" : "\\l'", stdout);
 174   printf("\\n[" WIDTH_FORMAT "]u-%dM",
 175          uid, 2*null_delimiter_space);
 176   fputs(draw_flag ? " 0'" : "\\&\\(ru'", stdout);
 177   printf("\\v'%dM'", axis_height);
 178   printf("\\h'%dM'", null_delimiter_space);
 179 }
 180
 181 void over_box::debug_print()
 182 {
 183   fprintf(stderr, "{ ");
 184   num->debug_print();
 185   if (reduce_size)
 186     fprintf(stderr, " } smallover { ");
 187   else
 188     fprintf(stderr, " } over { ");
 189   den->debug_print();
 190   fprintf(stderr, " }");
 191 }
 192
 193 void over_box::check_tabs(int level)
 194 {
 195   num->check_tabs(level + 1);
 196   den->check_tabs(level + 1);
 197 }