1 #ifndef lint 2 static char sccsid[] = "@(#)ti.c 4.2 08/11/83"; 3 #endif 4 5 /* ti.c: classify line intersections */ 6 # include "t..c" 7 /* determine local environment for intersections */ 8 interv(i,c) 9 { 10 int ku, kl; 11 if (c>=ncol || c == 0) 12 { 13 if (dboxflg) 14 { 15 if (i==0) return(BOT); 16 if (i>=nlin) return(TOP); 17 return(THRU); 18 } 19 if (c>=ncol) 20 return(0); 21 } 22 ku = i>0 ? lefdata(i-1,c) : 0; 23 if (i+1 >= nlin) 24 kl=0; 25 else 26 kl = lefdata(allh(i) ? i+1 : i, c); 27 if (ku==2 && kl==2) return(THRU); 28 if (ku ==2) return(TOP); 29 if (kl==BOT) return(2); 30 return(0); 31 } 32 interh(i,c) 33 { 34 int kl, kr; 35 if (fullbot[i]== '=' || (dboxflg && (i==0 || i>= nlin-1))) 36 { 37 if (c==ncol) 38 return(LEFT); 39 if (c==0) 40 return(RIGHT); 41 return(THRU); 42 } 43 if (i>=nlin) return(0); 44 kl = c>0 ? thish (i,c-1) : 0; 45 if (kl<=1 && i>0 && allh(up1(i))) 46 kl = c>0 ? thish(up1(i),c-1) : 0; 47 kr = thish(i,c); 48 if (kr<=1 && i>0 && allh(up1(i))) 49 kr = c>0 ? thish(up1(i), c) : 0; 50 if (kl== '=' && kr == '=') return(THRU); 51 if (kl== '=') return(LEFT); 52 if (kr== '=') return(RIGHT); 53 return(0); 54 } 55 up1(i) 56 { 57 i--; 58 while (instead[i] && i>0) i--; 59 return(i); 60 } 61