61 lines
1.3 KiB
C
Executable File
61 lines
1.3 KiB
C
Executable File
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
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/* All Rights Reserved */
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/* THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF AT&T */
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/* The copyright notice above does not evidence any */
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/* actual or intended publication of such source code. */
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#ident "@(#)subr.c 1.1 90/08/19 SMI" /* SVr4.0 1.1 */
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/*
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* Copyright (c) 1980 Regents of the University of California.
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* All rights reserved. The Berkeley software License Agreement
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* specifies the terms and conditions for redistribution.
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*/
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/*
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* Copyright (c) 1983, 1984 1985, 1986, 1987, 1988, Sun Microsystems, Inc.
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* All Rights Reserved.
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*/
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#include "dumb.h"
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/* Does not plot first point -- assumed that it is already plotted */
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dda_line(ch, x0, y0, x1, y1)
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char ch;
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int x0, y0; /* already transformed to screen coords */
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int x1, y1; /* untransformed */
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{
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int length, i;
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double deltaX, deltaY;
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double x, y;
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double floor();
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int abs();
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scale(x1, y1);
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length = abs(x1 - x0);
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if (abs(y1 -y0) > length)
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length = abs(y1 - y0);
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if (length == 0)
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return;
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deltaX = (double) (x1 - x0)/(double) length;
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deltaY = (double) (y1 - y0)/(double) length;
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x = (double) x0 + 0.5;
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y = (double) y0 + 0.5;
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for (i=0; i < length; ++i) {
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x += deltaX;
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y += deltaY;
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x0 = floor(x);
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y0 = floor(y);
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currentx = x0;
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currenty = y0;
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screenmat[currentx][currenty] = ch;
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}
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}
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