/*      @(#)wwredrawwin.c       8.1 (Berkeley) 6/6/93   */
/*      $NetBSD: wwredrawwin.c,v 1.7 2003/08/07 11:17:44 agc Exp $      */

/*
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Edward Wang at The University of California, Berkeley.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "ww.h"

void
wwredrawwin1(struct ww *w, int row1, int row2, int offset)
{
        int row;
        int col;
        unsigned char *smap;
        union ww_char *buf;
        char *win;
        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 > 0)
                        wwtouched[row] |= WWU_TOUCHED;
        }
}