1 /*
2  * Copyright (c) 1981, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifndef lint
31 static char sccsid[] = "@(#)overlay.c	8.2 (Berkeley) 5/4/94";
32 #endif	/* not lint */
33 
34 #include <ctype.h>
35 
36 #include "curses.h"
37 
38 /*
39  * overlay --
40  *	Writes win1 on win2 non-destructively.
41  */
42 int
overlay(win1,win2)43 overlay(win1, win2)
44 	register WINDOW *win1, *win2;
45 {
46 
47 	register int x, y, y1, y2, endy, endx, starty, startx;
48 	register __LDATA *sp, *end;
49 
50 #ifdef DEBUG
51 	__CTRACE("overlay: (%0.2o, %0.2o);\n", win1, win2);
52 #endif
53 	starty = max(win1->begy, win2->begy);
54 	startx = max(win1->begx, win2->begx);
55 	endy = min(win1->maxy + win1->begy, win2->maxy + win2->begx);
56 	endx = min(win1->maxx + win1->begx, win2->maxx + win2->begx);
57 #ifdef DEBUG
58 	__CTRACE("overlay: from (%d,%d) to (%d,%d)\n",
59 	    starty, startx, endy, endx);
60 #endif
61 	if (starty >= endy || startx >= endx)
62 		return (OK);
63 	y1 = starty - win1->begy;
64 	y2 = starty - win2->begy;
65 	for (y = starty; y < endy; y++, y1++, y2++) {
66 		end = &win1->lines[y1]->line[endx - win1->begx];
67 		x = startx - win2->begx;
68 		for (sp = &win1->lines[y1]->line[startx - win1->begx];
69 		     sp < end; sp++) {
70 			if (!isspace(sp->ch)) {
71 				wmove(win2, y2, x);
72 				__waddch(win2, sp);
73 			}
74 			x++;
75 		}
76 	}
77 	return (OK);
78 }
79