usr/src/usr.bin/window/wwredrawwin.c

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static char sccsid[] = "@(#)wwredrawwin.c       3.13 (Berkeley) %G%";
#endif /* not lint */

#include "ww.h"

wwredrawwin1(w, row1, row2, offset)
register struct ww *w;
int row1, row2, offset;
{
        int row;
        register col;
        register char *smap;
        register union ww_char *buf;
        register char *win;
        register union ww_char *ns;
        int x;
        int nchanged;

        for (row = row1; row < row2; row++) {
                col = w->ww_i.l;
                ns = wwns[row];
                smap = &wwsmap[row][col];
                buf = w->ww_buf[row + offset];
                win = w->ww_win[row];
                nchanged = 0;
                for (; col < w->ww_i.r; col++)
                        if (*smap++ == w->ww_index &&
                            ns[col].c_w !=
                            (x = buf[col].c_w ^ win[col] << WWC_MSHIFT)) {
                                nchanged++;
                                ns[col].c_w = x;
                        }
                if (nchanged > 4)
                        wwtouched[row] |= WWU_MAJOR|WWU_TOUCHED;
                else if (nchanged > 0)
                        wwtouched[row] |= WWU_TOUCHED;
        }
}