ref: c3ba64f6935322f09b6de5c2285544fd471c605d
dir: /sys/src/cmd/eqn/over.c/
#include "e.h" void boverb(int p1, int p2) { int treg; double h, b, d, d1, d2; extern double Overgap, Overwid, Overline; treg = salloc(); yyval = p1; d = EM(Overgap, ps); h = eht[p1] + eht[p2] + d; b = eht[p2] - d; dprintf(".\tS%d <- %d over %d; b=%g, h=%g\n", yyval, p1, p2, b, h); nrwid(p1, ps, p1); nrwid(p2, ps, p2); printf(".nr %d \\n(%d\n", treg, p1); printf(".if \\n(%d>\\n(%d .nr %d \\n(%d\n", p2, treg, treg, p2); printf(".nr %d \\n(%d+%gm\n", treg, treg, Overwid); d2 = eht[p2]-ebase[p2]-d; /* denom */ printf(".ds %d \\v'%gm'\\h'\\n(%du-\\n(%du/2u'\\*(%d\\v'%gm'\\\n", yyval, REL(d2,ps), treg, p2, p2, REL(-d2,ps)); d1 = 2 * d + ebase[p1]; /* num */ printf("\\h'-\\n(%du-\\n(%du/2u'\\v'%gm'\\*(%d\\v'%gm'\\\n", p2, p1, REL(-d1,ps), p1, REL(d1,ps)); printf("\\h'-\\n(%du-\\n(%du/2u+%gm'\\v'%gm'\\l'\\n(%du-%gm'\\h'%gm'\\v'%gm'\n", treg, p1, Overline, REL(-d,ps), treg, 2*Overline, Overline, REL(d,ps)); ebase[yyval] = b; eht[yyval] = h; lfont[yyval] = rfont[yyval] = 0; sfree(p2); sfree(treg); }