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/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Copyright (c) 1980 Regents of the University of California.
* All rights reserved. The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include "dumb.h"
/*
* Does not plot first point -- assumed that it is already plotted
*
* Parameters
* ch
* x0, y0 - already transformed to screen coords
* x1, y1 - untransformed
*/
void
dda_line(char ch, int x0, int y0, int x1, int y1)
{
int length, i;
double deltaX, deltaY;
double x, y;
double floor();
int abs();
scale(x1, y1);
length = abs(x1 - x0);
if (abs(y1 -y0) > length)
length = abs(y1 - y0);
if (length == 0)
return;
deltaX = (double) (x1 - x0)/(double) length;
deltaY = (double) (y1 - y0)/(double) length;
x = (double) x0 + 0.5;
y = (double) y0 + 0.5;
for (i=0; i < length; ++i) {
x += deltaX;
y += deltaY;
x0 = floor(x);
y0 = floor(y);
currentx = x0;
currenty = y0;
screenmat[currentx][currenty] = ch;
}
}
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