1 /*
2 * Copyright (c) 1981, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * %sccs.include.redist.c%
6 */
7
8 #ifndef lint
9 static char sccsid[] = "@(#)overlay.c 8.2 (Berkeley) 05/04/94";
10 #endif /* not lint */
11
12 #include <ctype.h>
13
14 #include "curses.h"
15
16 /*
17 * overlay --
18 * Writes win1 on win2 non-destructively.
19 */
20 int
overlay(win1,win2)21 overlay(win1, win2)
22 register WINDOW *win1, *win2;
23 {
24
25 register int x, y, y1, y2, endy, endx, starty, startx;
26 register __LDATA *sp, *end;
27
28 #ifdef DEBUG
29 __CTRACE("overlay: (%0.2o, %0.2o);\n", win1, win2);
30 #endif
31 starty = max(win1->begy, win2->begy);
32 startx = max(win1->begx, win2->begx);
33 endy = min(win1->maxy + win1->begy, win2->maxy + win2->begx);
34 endx = min(win1->maxx + win1->begx, win2->maxx + win2->begx);
35 #ifdef DEBUG
36 __CTRACE("overlay: from (%d,%d) to (%d,%d)\n",
37 starty, startx, endy, endx);
38 #endif
39 if (starty >= endy || startx >= endx)
40 return (OK);
41 y1 = starty - win1->begy;
42 y2 = starty - win2->begy;
43 for (y = starty; y < endy; y++, y1++, y2++) {
44 end = &win1->lines[y1]->line[endx - win1->begx];
45 x = startx - win2->begx;
46 for (sp = &win1->lines[y1]->line[startx - win1->begx];
47 sp < end; sp++) {
48 if (!isspace(sp->ch)) {
49 wmove(win2, y2, x);
50 __waddch(win2, sp);
51 }
52 x++;
53 }
54 }
55 return (OK);
56 }
57