eqn/special.cc

   1 // -*- C++ -*-
   2 /* Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
   3      Written by James Clark (jjc@jclark.com)
   4
   5 This file is part of groff.
   6
   7 groff 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, or (at your option) any later
  10 version.
  11
  12 groff is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License along
  18 with groff; see the file COPYING.  If not, write to the Free Software
  19 Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
  20
  21 #include "eqn.h"
  22 #include "pbox.h"
  23
  24 #define STRING_FORMAT PREFIX "str%d"
  25
  26 #define SPECIAL_STRING "0s"
  27 #define SPECIAL_WIDTH_REG "0w"
  28 #define SPECIAL_HEIGHT_REG "0h"
  29 #define SPECIAL_DEPTH_REG "0d"
  30 #define SPECIAL_SUB_KERN_REG "0skern"
  31 #define SPECIAL_SKEW_REG "0skew"
  32
  33 /*
  34 For example:
  35
  36 .de Cl
  37 .ds 0s \Z'\\*[0s]'\v'\\n(0du'\D'l \\n(0wu -\\n(0hu-\\n(0du'\v'\\n(0hu'
  38 ..
  39 .EQ
  40 define cancel 'special Cl'
  41 .EN
  42 */
  43
  44
  45 class special_box : public pointer_box {
  46   char *macro_name;
  47 public:
  48   special_box(char *, box *);
  49   ~special_box();
  50   int compute_metrics(int);
  51   void compute_subscript_kern();
  52   void compute_skew();
  53   void output();
  54   void debug_print();
  55 };
  56
  57 box *make_special_box(char *s, box *p)
  58 {
  59   return new special_box(s, p);
  60 }
  61
  62 special_box::special_box(char *s, box *pp) :macro_name(s), pointer_box(pp)
  63 {
  64 }
  65
  66 special_box::~special_box()
  67 {
  68   a_delete macro_name;
  69 }
  70
  71 int special_box::compute_metrics(int style)
  72 {
  73   int r = p->compute_metrics(style);
  74   p->compute_subscript_kern();
  75   p->compute_skew();
  76   printf(".ds " SPECIAL_STRING " \"");
  77   p->output();
  78   printf("\n");
  79   printf(".nr " SPECIAL_WIDTH_REG " 0\\n[" WIDTH_FORMAT "]\n", p->uid);
  80   printf(".nr " SPECIAL_HEIGHT_REG " \\n[" HEIGHT_FORMAT "]\n", p->uid);
  81   printf(".nr " SPECIAL_DEPTH_REG " \\n[" DEPTH_FORMAT "]\n", p->uid);
  82   printf(".nr " SPECIAL_SUB_KERN_REG " \\n[" SUB_KERN_FORMAT "]\n", p->uid);
  83   printf(".nr " SPECIAL_SKEW_REG " 0\\n[" SKEW_FORMAT "]\n", p->uid);
  84   printf(".%s\n", macro_name);
  85   printf(".rn " SPECIAL_STRING " " STRING_FORMAT "\n", uid);
  86   printf(".nr " WIDTH_FORMAT " 0\\n[" SPECIAL_WIDTH_REG "]\n", uid);
  87   printf(".nr " HEIGHT_FORMAT " 0>?\\n[" SPECIAL_HEIGHT_REG "]\n", uid);
  88   printf(".nr " DEPTH_FORMAT " 0>?\\n[" SPECIAL_DEPTH_REG "]\n", uid);
  89   printf(".nr " SUB_KERN_FORMAT " 0>?\\n[" SPECIAL_SUB_KERN_REG "]\n", uid);
  90   printf(".nr " SKEW_FORMAT " 0\\n[" SPECIAL_SKEW_REG "]\n", uid);
  91   // User will have to change MARK_REG if appropriate.
  92   return r;
  93 }
  94
  95 void special_box::compute_subscript_kern()
  96 {
  97   // Already computed in compute_metrics(), so do nothing.
  98 }
  99
 100 void special_box::compute_skew()
 101 {
 102   // Already computed in compute_metrics(), so do nothing.
 103 }
 104
 105 void special_box::output()
 106 {
 107   printf("\\*[" STRING_FORMAT "]", uid);
 108 }
 109
 110 void special_box::debug_print()
 111 {
 112   fprintf(stderr, "special %s { ", macro_name);
 113   p->debug_print();
 114   fprintf(stderr, " }");
 115 }