new version from arnold

[unix-history] / usr / src / lib / libcurses / overlay.c

# include	"curses.ext"
# include	<ctype.h>

# define	min(a,b)	(a < b ? a : b)
# define	max(a,b)	(a > b ? a : b)

/*
 *	This routine writes win1 on win2 non-destructively.
 *
 * @(#)overlay.c	1.6 (Berkeley) %G%
 */
overlay(win1, win2)
reg WINDOW	*win1, *win2; {

	reg char	*sp, *end;
	reg int		x, y, endy, endx, starty, startx;

# ifdef DEBUG
	fprintf(outf, "OVERLAY(%0.2o, %0.2o);\n", win1, win2);
# endif
	starty = max(win1->_begy, win2->_begy);
	startx = max(win1->_begx, win2->_begx);
	endy = min(win1->_maxy + win1->_begy, win2->_maxy + win2->_begx);
	endx = min(win1->_maxx + win1->_begx, win2->_maxx + win2->_begx);
# ifdef DEBUG
	fprintf(outf, "OVERLAY:from (%d,%d) to (%d,%d)\n", starty, startx, endy, endx);
# endif
	if (starty >= endy || startx >= endx)
		return;
	x = endx - startx;
	for (y = starty; y < endy; y++) {
		bcopy(&win1->_y[y - win1->_begy][startx - win1->_begx],
		      &win2->_y[y - win2->_begy][startx - win2->_begx], x);
		touchline(win2, y, startx - win2->_begx, endx - win2->_begx);
	}
	for (y = starty; y < endy; y++) {
		end = &win1->_y[y - win1->_begy][endx - win1->_begx];
		x = startx - win2->_begx;
		for (sp = &win1->_y[y][startx - win1->_begx]; sp < end; sp++) {
			if (!isspace(*sp)) {
				waddch(win2, y - win2->_begy, x);
				waddch(win2, *sp);
			}
			x++;
		}
	}
}