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