sys/src/cmd/eqn/fromto.c

   1 # include "e.h"
   2
   3 void fromto(int p1, int p2, int p3)
   4 {
   5         double b, h1, b1, t;
   6         int subps;
   7
   8         yyval = salloc();
   9         lfont[yyval] = rfont[yyval] = 0;
  10         h1 = eht[yyval] = eht[p1];
  11         b1 = ebase[p1];
  12         b = 0;
  13         subps = ps;
  14         ps += deltaps;
  15         nrwid(p1, ps, p1);
  16         printf(".nr %d \\n(%d\n", yyval, p1);
  17         if (p2 > 0) {
  18                 nrwid(p2, subps, p2);
  19                 printf(".if \\n(%d>\\n(%d .nr %d \\n(%d\n", p2, yyval, yyval, p2);
  20                 eht[yyval] += eht[p2];
  21                 b = eht[p2];
  22         }
  23         if (p3 > 0) {
  24                 nrwid(p3, subps, p3);
  25                 printf(".if \\n(%d>\\n(%d .nr %d \\n(%d\n", p3, yyval, yyval, p3);
  26                 eht[yyval] += eht[p3];
  27         }
  28         printf(".ds %d ", yyval);       /* bottom of middle box */
  29         if (p2 > 0) {
  30                 t = eht[p2]-ebase[p2]+b1;
  31                 printf("\\v'%gm'\\h'\\n(%du-\\n(%du/2u'%s\\*(%d%s",
  32                         REL(t,ps), yyval, p2, DPS(ps,subps), p2, DPS(subps,ps));
  33                 printf("\\h'-\\n(%du-\\n(%du/2u'\\v'%gm'\\\n",
  34                         yyval, p2, REL(-t,ps));
  35         }
  36         printf("\\h'\\n(%du-\\n(%du/2u'\\*(%d\\h'\\n(%du-\\n(%du/2u'\\\n",
  37                 yyval, p1, p1, yyval, p1);
  38         if (p3  >0) {
  39                 t = h1-b1+ebase[p3];
  40                 printf("\\v'%gm'\\h'-\\n(%du-\\n(%du/2u'%s\\*(%d%s\\h'\\n(%du-\\n(%du/2u'\\v'%gm'\\\n",
  41                         REL(-t,ps), yyval, p3, DPS(ps,subps), p3, DPS(subps,ps), yyval, p3, REL(t,ps));
  42         }
  43         printf("\n");
  44         ebase[yyval] = b + b1;
  45         dprintf(".\tS%d <- %d from %d to %d; h=%g b=%g\n",
  46                 yyval, p1, p2, p3, eht[yyval], ebase[yyval]);
  47         sfree(p1);
  48         if (p2 > 0)
  49                 sfree(p2);
  50         if (p3 > 0)
  51                 sfree(p3);
  52 }