1 /*
2 * Copyright 1990 Sun Microsystems, Inc. All rights reserved.
3 * Use is subject to license terms.
4 */
5
6 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
7 /* All Rights Reserved */
8
9 /*
10 * Copyright (c) 1980 Regents of the University of California.
11 * All rights reserved. The Berkeley software License Agreement
12 * specifies the terms and conditions for redistribution.
13 */
14
15 /* ti.c: classify line intersections */
16 # include "t..c"
17 /* determine local environment for intersections */
18
19 int
interv(int i,int c)20 interv(int i, int c)
21 {
22 int ku, kl;
23 if (c>=ncol || c == 0)
24 {
25 if (dboxflg)
26 {
27 if (i==0) return(BOT);
28 if (i>=nlin) return(TOP);
29 return(THRU);
30 }
31 if (c>=ncol)
32 return(0);
33 }
34 ku = i>0 ? lefdata(i-1,c) : 0;
35 if (i+1 >= nlin)
36 kl=0;
37 else
38 kl = lefdata(allh(i) ? i+1 : i, c);
39 if (ku==2 && kl==2) return(THRU);
40 if (ku ==2) return(TOP);
41 if (kl==BOT) return(2);
42 return(0);
43 }
44
45 int
interh(int i,int c)46 interh(int i, int c)
47 {
48 int kl, kr;
49 if (fullbot[i]== '=' || (dboxflg && (i==0 || i>= nlin-1)))
50 {
51 if (c==ncol)
52 return(LEFT);
53 if (c==0)
54 return(RIGHT);
55 return(THRU);
56 }
57 if (i>=nlin) return(0);
58 kl = c>0 ? thish (i,c-1) : 0;
59 if (kl<=1 && i>0 && allh(up1(i)))
60 kl = c>0 ? thish(up1(i),c-1) : 0;
61 kr = thish(i,c);
62 if (kr<=1 && i>0 && allh(up1(i)))
63 kr = c>0 ? thish(up1(i), c) : 0;
64 if (kl== '=' && kr == '=') return(THRU);
65 if (kl== '=') return(LEFT);
66 if (kr== '=') return(RIGHT);
67 return(0);
68 }
69
70 int
up1(int i)71 up1(int i)
72 {
73 i--;
74 while (instead[i] && i>0) i--;
75 return(i);
76 }
77