1*11042Sshannon /* ti.c 4.1 83/02/12 */ 2*11042Sshannon 3*11042Sshannon /* ti.c: classify line intersections */ 4*11042Sshannon # include "t..c" 5*11042Sshannon /* determine local environment for intersections */ 6*11042Sshannon interv(i,c) 7*11042Sshannon { 8*11042Sshannon int ku, kl; 9*11042Sshannon if (c>=ncol || c == 0) 10*11042Sshannon { 11*11042Sshannon if (dboxflg) 12*11042Sshannon { 13*11042Sshannon if (i==0) return(BOT); 14*11042Sshannon if (i>=nlin) return(TOP); 15*11042Sshannon return(THRU); 16*11042Sshannon } 17*11042Sshannon if (c>=ncol) 18*11042Sshannon return(0); 19*11042Sshannon } 20*11042Sshannon ku = i>0 ? lefdata(i-1,c) : 0; 21*11042Sshannon if (i+1 >= nlin) 22*11042Sshannon kl=0; 23*11042Sshannon else 24*11042Sshannon kl = lefdata(allh(i) ? i+1 : i, c); 25*11042Sshannon if (ku==2 && kl==2) return(THRU); 26*11042Sshannon if (ku ==2) return(TOP); 27*11042Sshannon if (kl==BOT) return(2); 28*11042Sshannon return(0); 29*11042Sshannon } 30*11042Sshannon interh(i,c) 31*11042Sshannon { 32*11042Sshannon int kl, kr; 33*11042Sshannon if (fullbot[i]== '=' || (dboxflg && (i==0 || i>= nlin-1))) 34*11042Sshannon { 35*11042Sshannon if (c==ncol) 36*11042Sshannon return(LEFT); 37*11042Sshannon if (c==0) 38*11042Sshannon return(RIGHT); 39*11042Sshannon return(THRU); 40*11042Sshannon } 41*11042Sshannon if (i>=nlin) return(0); 42*11042Sshannon kl = c>0 ? thish (i,c-1) : 0; 43*11042Sshannon if (kl<=1 && i>0 && allh(up1(i))) 44*11042Sshannon kl = c>0 ? thish(up1(i),c-1) : 0; 45*11042Sshannon kr = thish(i,c); 46*11042Sshannon if (kr<=1 && i>0 && allh(up1(i))) 47*11042Sshannon kr = c>0 ? thish(up1(i), c) : 0; 48*11042Sshannon if (kl== '=' && kr == '=') return(THRU); 49*11042Sshannon if (kl== '=') return(LEFT); 50*11042Sshannon if (kr== '=') return(RIGHT); 51*11042Sshannon return(0); 52*11042Sshannon } 53*11042Sshannon up1(i) 54*11042Sshannon { 55*11042Sshannon i--; 56*11042Sshannon while (instead[i] && i>0) i--; 57*11042Sshannon return(i); 58*11042Sshannon } 59