t300/common/line.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*  Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*    All Rights Reserved   */


/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"    /* SVr4.0 1.2   */
/*LINTLIBRARY*/

#include <stdlib.h>
#include <math.h>
#include "con.h"

short xnow, ynow;

static void
iline(short cx0, short cy0, short cx1, short cy1)
{
    int maxp, tt;
    short j;
    char chx, chy;
    float xd, yd;

        movep(cx0, cy0);
        maxp = (int)(sqrt(dist2(cx0, cy0, cx1, cy1)) / 2.);
        xd = cx1 - cx0;
        yd = cy1 - cy0;
        if (xd >= 0)
            chx = RIGHT;
        else chx = LEFT;
        if (yd >= 0)
            chy = UP;
        else chy = DOWN;
        if (maxp == 0) {
            xd = 0;
            yd = 0;
        } else {
            xd /= maxp;
            yd /= maxp;
        }
        inplot();
        for (tt = 0; tt <= maxp; tt++) {
            j = (short)(cx0 + xd * tt - xnow);
            xnow += j;
            j = abs(j);
            while (j-- > 0)
                spew(chx);
            j = (short)(cy0 + yd * tt - ynow);
            ynow += j;
            j = abs(j);
            while (j-- > 0)
                spew(chy);
            spew('.');
        }
        outplot();
}

void
line(short x0, short y0, short x1, short y1)
{
    iline(xconv(xsc(x0)), yconv(ysc(y0)),
        xconv(xsc(x1)), yconv(ysc(y1)));
}


void
cont(short x0, short y0)
{
    iline(xnow, ynow, xconv(xsc(x0)), yconv(ysc(y0)));
}