overlay.c revision 1.7 
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. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static char sccsid[] = "@(#)overlay.c	8.2 (Berkeley) 5/4/94";
36#endif	/* not lint */
37
38#include <ctype.h>
39
40#include "curses.h"
41
42/*
43 * overlay --
44 *	Writes win1 on win2 non-destructively.
45 */
46int
47overlay(win1, win2)
48	register WINDOW *win1, *win2;
49{
50
51	register int x, y, y1, y2, endy, endx, starty, startx;
52	register __LDATA *sp, *end;
53
54#ifdef DEBUG
55	__CTRACE("overlay: (%0.2o, %0.2o);\n", win1, win2);
56#endif
57	starty = max(win1->begy, win2->begy);
58	startx = max(win1->begx, win2->begx);
59	endy = min(win1->maxy + win1->begy, win2->maxy + win2->begx);
60	endx = min(win1->maxx + win1->begx, win2->maxx + win2->begx);
61#ifdef DEBUG
62	__CTRACE("overlay: from (%d,%d) to (%d,%d)\n",
63	    starty, startx, endy, endx);
64#endif
65	if (starty >= endy || startx >= endx)
66		return (OK);
67	y1 = starty - win1->begy;
68	y2 = starty - win2->begy;
69	for (y = starty; y < endy; y++, y1++, y2++) {
70		end = &win1->lines[y1]->line[endx - win1->begx];
71		x = startx - win2->begx;
72		for (sp = &win1->lines[y1]->line[startx - win1->begx];
73		     sp < end; sp++) {
74			if (!isspace(sp->ch)) {
75				wmove(win2, y2, x);
76				__waddch(win2, sp);
77			}
78			x++;
79		}
80	}
81	return (OK);
82}
83