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/* Segment.java -- Abstract segment used for BasicStroke
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Copyright (C) 2006 Free Software Foundation, Inc.
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This file is part of GNU Classpath.
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GNU Classpath is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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GNU Classpath is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU Classpath; see the file COPYING. If not, write to the
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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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Linking this library statically or dynamically with other modules is
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making a combined work based on this library. Thus, the terms and
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conditions of the GNU General Public License cover the whole
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As a special exception, the copyright holders of this library give you
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permission to link this library with independent modules to produce an
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executable, regardless of the license terms of these independent
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modules, and to copy and distribute the resulting executable under
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terms of your choice, provided that you also meet, for each linked
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independent module, the terms and conditions of the license of that
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module. An independent module is a module which is not derived from
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or based on this library. If you modify this library, you may extend
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this exception to your version of the library, but you are not
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obligated to do so. If you do not wish to do so, delete this
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exception statement from your version. */
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package gnu.java.awt.java2d;
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import java.awt.geom.Point2D;
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public abstract class Segment implements Cloneable
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// segment type, PathIterator segment types are used.
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protected double radius;
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public void add(Segment newsegment)
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last.next = newsegment;
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* Reverses the orientation of the whole polygon
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public void reverseAll()
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Segment former = this;
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Segment oldnext = v.next;
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v = oldnext; // move to the next in list
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public String toString()
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return "Segment:"+P1+", "+P2;
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* Get the normal vector to the slope of the line.
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* Returns: 0.5*width*(norm of derivative of the (x0,y0)-(x1,y1) vector)
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protected double[] normal(double x0, double y0, double x1, double y1)
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double dx = (x1 - x0);
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double dy = (y1 - y0);
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dy = radius * ((dx > 0)?1:-1);
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dx = radius * ((dy > 0)?-1:1);
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double N = Math.sqrt(dx * dx + dy * dy);
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dx = -radius * dy / N;
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dy = radius * odx / N;
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return new double[]{ dx, dy };
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public abstract void reverse();
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* Get the "top" and "bottom" segments of a segment.
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* First array element is p0 + normal, second is p0 - normal.
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public abstract Segment[] getDisplacedSegments(double radius);
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public abstract double[] first();
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public abstract double[] last();