1183 lines
35 KiB
Java
1183 lines
35 KiB
Java
/* Line2D.java -- represents a line in 2-D space, plus operations on a line
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Copyright (C) 2000, 2001, 2002 Free Software Foundation
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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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any later version.
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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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02110-1301 USA.
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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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combination.
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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 java.awt.geom;
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import java.awt.Rectangle;
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import java.awt.Shape;
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import java.util.NoSuchElementException;
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/**
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* Represents a directed line bewteen two points in (x,y) Cartesian space.
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* Remember, on-screen graphics have increasing x from left-to-right, and
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* increasing y from top-to-bottom. The storage is left to subclasses.
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*
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* @author Tom Tromey (tromey@cygnus.com)
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* @author Eric Blake (ebb9@email.byu.edu)
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* @author David Gilbert
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* @since 1.2
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* @status updated to 1.4
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*/
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public abstract class Line2D implements Shape, Cloneable
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{
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/**
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* The default constructor.
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*/
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protected Line2D()
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{
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}
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/**
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* Return the x coordinate of the first point.
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*
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* @return the starting x coordinate
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*/
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public abstract double getX1();
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/**
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* Return the y coordinate of the first point.
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*
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* @return the starting y coordinate
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*/
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public abstract double getY1();
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/**
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* Return the first point.
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*
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* @return the starting point
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*/
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public abstract Point2D getP1();
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/**
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* Return the x coordinate of the second point.
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*
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* @return the ending x coordinate
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*/
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public abstract double getX2();
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/**
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* Return the y coordinate of the second point.
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*
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* @return the ending y coordinate
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*/
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public abstract double getY2();
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/**
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* Return the second point.
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*
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* @return the ending point
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*/
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public abstract Point2D getP2();
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/**
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* Set the coordinates of the line to the given coordinates. Loss of
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* precision may occur due to rounding issues.
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*
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* @param x1 the first x coordinate
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* @param y1 the first y coordinate
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* @param x2 the second x coordinate
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* @param y2 the second y coordinate
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*/
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public abstract void setLine(double x1, double y1, double x2, double y2);
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/**
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* Set the coordinates to the given points.
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*
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* @param p1 the first point
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* @param p2 the second point
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* @throws NullPointerException if either point is null
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*/
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public void setLine(Point2D p1, Point2D p2)
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{
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setLine(p1.getX(), p1.getY(), p2.getX(), p2.getY());
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}
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/**
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* Set the coordinates to those of the given line.
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*
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* @param l the line to copy
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* @throws NullPointerException if l is null
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*/
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public void setLine(Line2D l)
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{
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setLine(l.getX1(), l.getY1(), l.getX2(), l.getY2());
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}
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/**
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* Computes the relative rotation direction needed to pivot the line about
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* the first point in order to have the second point colinear with point p.
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* Because of floating point rounding, don't expect this to be a perfect
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* measure of colinearity. The answer is 1 if the line has a shorter rotation
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* in the direction of the positive X axis to the negative Y axis
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* (counter-clockwise in the default Java coordinate system), or -1 if the
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* shortest rotation is in the opposite direction (clockwise). If p
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* is already colinear, the return value is -1 if it lies beyond the first
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* point, 0 if it lies in the segment, or 1 if it lies beyond the second
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* point. If the first and second point are coincident, this returns 0.
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*
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* @param x1 the first x coordinate
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* @param y1 the first y coordinate
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* @param x2 the second x coordinate
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* @param y2 the second y coordinate
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* @param px the reference x coordinate
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* @param py the reference y coordinate
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* @return the relative rotation direction
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*/
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public static int relativeCCW(double x1, double y1, double x2, double y2,
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double px, double py)
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{
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if ((x1 == x2 && y1 == y2)
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|| (x1 == px && y1 == py))
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return 0; // Coincident points.
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// Translate to the origin.
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x2 -= x1;
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y2 -= y1;
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px -= x1;
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py -= y1;
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double slope2 = y2 / x2;
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double slopep = py / px;
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if (slope2 == slopep || (x2 == 0 && px == 0))
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return y2 > 0 // Colinear.
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? (py < 0 ? -1 : py > y2 ? 1 : 0)
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: (py > 0 ? -1 : py < y2 ? 1 : 0);
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if (x2 >= 0 && slope2 >= 0)
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return px >= 0 // Quadrant 1.
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? (slope2 > slopep ? 1 : -1)
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: (slope2 < slopep ? 1 : -1);
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if (y2 > 0)
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return px < 0 // Quadrant 2.
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? (slope2 > slopep ? 1 : -1)
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: (slope2 < slopep ? 1 : -1);
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if (slope2 >= 0.0)
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return px >= 0 // Quadrant 3.
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? (slope2 < slopep ? 1 : -1)
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: (slope2 > slopep ? 1 : -1);
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return px < 0 // Quadrant 4.
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? (slope2 < slopep ? 1 : -1)
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: (slope2 > slopep ? 1 : -1);
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}
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/**
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* Computes the relative rotation direction needed to pivot this line about
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* the first point in order to have the second point colinear with point p.
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* Because of floating point rounding, don't expect this to be a perfect
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* measure of colinearity. The answer is 1 if the line has a shorter rotation
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* in the direction of the positive X axis to the negative Y axis
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* (counter-clockwise in the default Java coordinate system), or -1 if the
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* shortest rotation is in the opposite direction (clockwise). If p
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* is already colinear, the return value is -1 if it lies beyond the first
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* point, 0 if it lies in the segment, or 1 if it lies beyond the second
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* point. If the first and second point are coincident, this returns 0.
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*
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* @param px the reference x coordinate
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* @param py the reference y coordinate
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* @return the relative rotation direction
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* @see #relativeCCW(double, double, double, double, double, double)
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*/
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public int relativeCCW(double px, double py)
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{
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return relativeCCW(getX1(), getY1(), getX2(), getY2(), px, py);
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}
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/**
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* Computes the relative rotation direction needed to pivot this line about
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* the first point in order to have the second point colinear with point p.
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* Because of floating point rounding, don't expect this to be a perfect
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* measure of colinearity. The answer is 1 if the line has a shorter rotation
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* in the direction of the positive X axis to the negative Y axis
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* (counter-clockwise in the default Java coordinate system), or -1 if the
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* shortest rotation is in the opposite direction (clockwise). If p
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* is already colinear, the return value is -1 if it lies beyond the first
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* point, 0 if it lies in the segment, or 1 if it lies beyond the second
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* point. If the first and second point are coincident, this returns 0.
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*
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* @param p the reference point
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* @return the relative rotation direction
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* @throws NullPointerException if p is null
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* @see #relativeCCW(double, double, double, double, double, double)
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*/
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public int relativeCCW(Point2D p)
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{
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return relativeCCW(getX1(), getY1(), getX2(), getY2(), p.getX(), p.getY());
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}
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/**
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* Computes twice the (signed) area of the triangle defined by the three
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* points. This method is used for intersection testing.
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*
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* @param x1 the x-coordinate of the first point.
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* @param y1 the y-coordinate of the first point.
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* @param x2 the x-coordinate of the second point.
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* @param y2 the y-coordinate of the second point.
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* @param x3 the x-coordinate of the third point.
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* @param y3 the y-coordinate of the third point.
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*
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* @return Twice the area.
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*/
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private static double area2(double x1, double y1,
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double x2, double y2,
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double x3, double y3)
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{
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return (x2 - x1) * (y3 - y1) - (x3 - x1) * (y2 - y1);
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}
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/**
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* Returns <code>true</code> if (x3, y3) lies between (x1, y1) and (x2, y2),
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* and false otherwise, This test assumes that the three points are
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* collinear, and is used for intersection testing.
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*
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* @param x1 the x-coordinate of the first point.
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* @param y1 the y-coordinate of the first point.
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* @param x2 the x-coordinate of the second point.
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* @param y2 the y-coordinate of the second point.
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* @param x3 the x-coordinate of the third point.
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* @param y3 the y-coordinate of the third point.
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*
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* @return A boolean.
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*/
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private static boolean between(double x1, double y1,
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double x2, double y2,
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double x3, double y3)
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{
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if (x1 != x2) {
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return (x1 <= x3 && x3 <= x2) || (x1 >= x3 && x3 >= x2);
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}
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else {
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return (y1 <= y3 && y3 <= y2) || (y1 >= y3 && y3 >= y2);
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}
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}
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/**
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* Test if the line segment (x1,y1)->(x2,y2) intersects the line segment
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* (x3,y3)->(x4,y4).
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*
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* @param x1 the first x coordinate of the first segment
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* @param y1 the first y coordinate of the first segment
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* @param x2 the second x coordinate of the first segment
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* @param y2 the second y coordinate of the first segment
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* @param x3 the first x coordinate of the second segment
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* @param y3 the first y coordinate of the second segment
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* @param x4 the second x coordinate of the second segment
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* @param y4 the second y coordinate of the second segment
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* @return true if the segments intersect
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*/
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public static boolean linesIntersect(double x1, double y1,
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double x2, double y2,
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double x3, double y3,
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double x4, double y4)
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{
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double a1, a2, a3, a4;
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// deal with special cases
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if ((a1 = area2(x1, y1, x2, y2, x3, y3)) == 0.0)
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{
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// check if p3 is between p1 and p2 OR
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// p4 is collinear also AND either between p1 and p2 OR at opposite ends
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if (between(x1, y1, x2, y2, x3, y3))
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{
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return true;
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}
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else
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{
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if (area2(x1, y1, x2, y2, x4, y4) == 0.0)
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{
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return between(x3, y3, x4, y4, x1, y1)
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|| between (x3, y3, x4, y4, x2, y2);
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}
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else {
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return false;
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}
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}
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}
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else if ((a2 = area2(x1, y1, x2, y2, x4, y4)) == 0.0)
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{
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// check if p4 is between p1 and p2 (we already know p3 is not
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// collinear)
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return between(x1, y1, x2, y2, x4, y4);
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}
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if ((a3 = area2(x3, y3, x4, y4, x1, y1)) == 0.0) {
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// check if p1 is between p3 and p4 OR
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// p2 is collinear also AND either between p1 and p2 OR at opposite ends
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if (between(x3, y3, x4, y4, x1, y1)) {
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return true;
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}
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else {
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if (area2(x3, y3, x4, y4, x2, y2) == 0.0) {
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return between(x1, y1, x2, y2, x3, y3)
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|| between (x1, y1, x2, y2, x4, y4);
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}
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else {
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return false;
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}
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}
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}
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else if ((a4 = area2(x3, y3, x4, y4, x2, y2)) == 0.0) {
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// check if p2 is between p3 and p4 (we already know p1 is not
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// collinear)
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return between(x3, y3, x4, y4, x2, y2);
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}
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else { // test for regular intersection
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return ((a1 > 0.0) ^ (a2 > 0.0)) && ((a3 > 0.0) ^ (a4 > 0.0));
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}
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}
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/**
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* Test if this line intersects the line given by (x1,y1)->(x2,y2).
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*
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* @param x1 the first x coordinate of the other segment
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* @param y1 the first y coordinate of the other segment
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* @param x2 the second x coordinate of the other segment
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* @param y2 the second y coordinate of the other segment
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* @return true if the segments intersect
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* @see #linesIntersect(double, double, double, double,
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* double, double, double, double)
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*/
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public boolean intersectsLine(double x1, double y1, double x2, double y2)
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{
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return linesIntersect(getX1(), getY1(), getX2(), getY2(),
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x1, y1, x2, y2);
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}
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/**
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* Test if this line intersects the given line.
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*
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* @param l the other segment
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* @return true if the segments intersect
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* @throws NullPointerException if l is null
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* @see #linesIntersect(double, double, double, double,
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* double, double, double, double)
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*/
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public boolean intersectsLine(Line2D l)
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{
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return linesIntersect(getX1(), getY1(), getX2(), getY2(),
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l.getX1(), l.getY1(), l.getX2(), l.getY2());
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}
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/**
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* Measures the square of the shortest distance from the reference point
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* to a point on the line segment. If the point is on the segment, the
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* result will be 0.
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*
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* @param x1 the first x coordinate of the segment
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* @param y1 the first y coordinate of the segment
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* @param x2 the second x coordinate of the segment
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* @param y2 the second y coordinate of the segment
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* @param px the x coordinate of the point
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* @param py the y coordinate of the point
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* @return the square of the distance from the point to the segment
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* @see #ptSegDist(double, double, double, double, double, double)
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* @see #ptLineDistSq(double, double, double, double, double, double)
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*/
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public static double ptSegDistSq(double x1, double y1, double x2, double y2,
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double px, double py)
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{
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double pd2 = (x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2);
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double x, y;
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if (pd2 == 0)
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{
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// Points are coincident.
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x = x1;
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y = y2;
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}
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else
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{
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double u = ((px - x1) * (x2 - x1) + (py - y1) * (y2 - y1)) / pd2;
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if (u < 0)
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{
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// "Off the end"
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x = x1;
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y = y1;
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}
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else if (u > 1.0)
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{
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x = x2;
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y = y2;
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}
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else
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{
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x = x1 + u * (x2 - x1);
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y = y1 + u * (y2 - y1);
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}
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}
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return (x - px) * (x - px) + (y - py) * (y - py);
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}
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/**
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* Measures the shortest distance from the reference point to a point on
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* the line segment. If the point is on the segment, the result will be 0.
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*
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* @param x1 the first x coordinate of the segment
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* @param y1 the first y coordinate of the segment
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* @param x2 the second x coordinate of the segment
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* @param y2 the second y coordinate of the segment
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* @param px the x coordinate of the point
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* @param py the y coordinate of the point
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* @return the distance from the point to the segment
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* @see #ptSegDistSq(double, double, double, double, double, double)
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* @see #ptLineDist(double, double, double, double, double, double)
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*/
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public static double ptSegDist(double x1, double y1, double x2, double y2,
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double px, double py)
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{
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return Math.sqrt(ptSegDistSq(x1, y1, x2, y2, px, py));
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}
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/**
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* Measures the square of the shortest distance from the reference point
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* to a point on this line segment. If the point is on the segment, the
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* result will be 0.
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*
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* @param px the x coordinate of the point
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* @param py the y coordinate of the point
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* @return the square of the distance from the point to the segment
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* @see #ptSegDistSq(double, double, double, double, double, double)
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*/
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public double ptSegDistSq(double px, double py)
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{
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return ptSegDistSq(getX1(), getY1(), getX2(), getY2(), px, py);
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}
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/**
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* Measures the square of the shortest distance from the reference point
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* to a point on this line segment. If the point is on the segment, the
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* result will be 0.
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*
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* @param p the point
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* @return the square of the distance from the point to the segment
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* @throws NullPointerException if p is null
|
|
* @see #ptSegDistSq(double, double, double, double, double, double)
|
|
*/
|
|
public double ptSegDistSq(Point2D p)
|
|
{
|
|
return ptSegDistSq(getX1(), getY1(), getX2(), getY2(), p.getX(), p.getY());
|
|
}
|
|
|
|
/**
|
|
* Measures the shortest distance from the reference point to a point on
|
|
* this line segment. If the point is on the segment, the result will be 0.
|
|
*
|
|
* @param px the x coordinate of the point
|
|
* @param py the y coordinate of the point
|
|
* @return the distance from the point to the segment
|
|
* @see #ptSegDist(double, double, double, double, double, double)
|
|
*/
|
|
public double ptSegDist(double px, double py)
|
|
{
|
|
return ptSegDist(getX1(), getY1(), getX2(), getY2(), px, py);
|
|
}
|
|
|
|
/**
|
|
* Measures the shortest distance from the reference point to a point on
|
|
* this line segment. If the point is on the segment, the result will be 0.
|
|
*
|
|
* @param p the point
|
|
* @return the distance from the point to the segment
|
|
* @throws NullPointerException if p is null
|
|
* @see #ptSegDist(double, double, double, double, double, double)
|
|
*/
|
|
public double ptSegDist(Point2D p)
|
|
{
|
|
return ptSegDist(getX1(), getY1(), getX2(), getY2(), p.getX(), p.getY());
|
|
}
|
|
|
|
/**
|
|
* Measures the square of the shortest distance from the reference point
|
|
* to a point on the infinite line extended from the segment. If the point
|
|
* is on the segment, the result will be 0. If the segment is length 0,
|
|
* the distance is to the common endpoint.
|
|
*
|
|
* @param x1 the first x coordinate of the segment
|
|
* @param y1 the first y coordinate of the segment
|
|
* @param x2 the second x coordinate of the segment
|
|
* @param y2 the second y coordinate of the segment
|
|
* @param px the x coordinate of the point
|
|
* @param py the y coordinate of the point
|
|
* @return the square of the distance from the point to the extended line
|
|
* @see #ptLineDist(double, double, double, double, double, double)
|
|
* @see #ptSegDistSq(double, double, double, double, double, double)
|
|
*/
|
|
public static double ptLineDistSq(double x1, double y1, double x2, double y2,
|
|
double px, double py)
|
|
{
|
|
double pd2 = (x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2);
|
|
|
|
double x, y;
|
|
if (pd2 == 0)
|
|
{
|
|
// Points are coincident.
|
|
x = x1;
|
|
y = y2;
|
|
}
|
|
else
|
|
{
|
|
double u = ((px - x1) * (x2 - x1) + (py - y1) * (y2 - y1)) / pd2;
|
|
x = x1 + u * (x2 - x1);
|
|
y = y1 + u * (y2 - y1);
|
|
}
|
|
|
|
return (x - px) * (x - px) + (y - py) * (y - py);
|
|
}
|
|
|
|
/**
|
|
* Measures the shortest distance from the reference point to a point on
|
|
* the infinite line extended from the segment. If the point is on the
|
|
* segment, the result will be 0. If the segment is length 0, the distance
|
|
* is to the common endpoint.
|
|
*
|
|
* @param x1 the first x coordinate of the segment
|
|
* @param y1 the first y coordinate of the segment
|
|
* @param x2 the second x coordinate of the segment
|
|
* @param y2 the second y coordinate of the segment
|
|
* @param px the x coordinate of the point
|
|
* @param py the y coordinate of the point
|
|
* @return the distance from the point to the extended line
|
|
* @see #ptLineDistSq(double, double, double, double, double, double)
|
|
* @see #ptSegDist(double, double, double, double, double, double)
|
|
*/
|
|
public static double ptLineDist(double x1, double y1,
|
|
double x2, double y2,
|
|
double px, double py)
|
|
{
|
|
return Math.sqrt(ptLineDistSq(x1, y1, x2, y2, px, py));
|
|
}
|
|
|
|
/**
|
|
* Measures the square of the shortest distance from the reference point
|
|
* to a point on the infinite line extended from this segment. If the point
|
|
* is on the segment, the result will be 0. If the segment is length 0,
|
|
* the distance is to the common endpoint.
|
|
*
|
|
* @param px the x coordinate of the point
|
|
* @param py the y coordinate of the point
|
|
* @return the square of the distance from the point to the extended line
|
|
* @see #ptLineDistSq(double, double, double, double, double, double)
|
|
*/
|
|
public double ptLineDistSq(double px, double py)
|
|
{
|
|
return ptLineDistSq(getX1(), getY1(), getX2(), getY2(), px, py);
|
|
}
|
|
|
|
/**
|
|
* Measures the square of the shortest distance from the reference point
|
|
* to a point on the infinite line extended from this segment. If the point
|
|
* is on the segment, the result will be 0. If the segment is length 0,
|
|
* the distance is to the common endpoint.
|
|
*
|
|
* @param p the point
|
|
* @return the square of the distance from the point to the extended line
|
|
* @throws NullPointerException if p is null
|
|
* @see #ptLineDistSq(double, double, double, double, double, double)
|
|
*/
|
|
public double ptLineDistSq(Point2D p)
|
|
{
|
|
return ptLineDistSq(getX1(), getY1(), getX2(), getY2(),
|
|
p.getX(), p.getY());
|
|
}
|
|
|
|
/**
|
|
* Measures the shortest distance from the reference point to a point on
|
|
* the infinite line extended from this segment. If the point is on the
|
|
* segment, the result will be 0. If the segment is length 0, the distance
|
|
* is to the common endpoint.
|
|
*
|
|
* @param px the x coordinate of the point
|
|
* @param py the y coordinate of the point
|
|
* @return the distance from the point to the extended line
|
|
* @see #ptLineDist(double, double, double, double, double, double)
|
|
*/
|
|
public double ptLineDist(double px, double py)
|
|
{
|
|
return ptLineDist(getX1(), getY1(), getX2(), getY2(), px, py);
|
|
}
|
|
|
|
/**
|
|
* Measures the shortest distance from the reference point to a point on
|
|
* the infinite line extended from this segment. If the point is on the
|
|
* segment, the result will be 0. If the segment is length 0, the distance
|
|
* is to the common endpoint.
|
|
*
|
|
* @param p the point
|
|
* @return the distance from the point to the extended line
|
|
* @throws NullPointerException if p is null
|
|
* @see #ptLineDist(double, double, double, double, double, double)
|
|
*/
|
|
public double ptLineDist(Point2D p)
|
|
{
|
|
return ptLineDist(getX1(), getY1(), getX2(), getY2(), p.getX(), p.getY());
|
|
}
|
|
|
|
/**
|
|
* Test if a point is contained inside the line. Since a line has no area,
|
|
* this returns false.
|
|
*
|
|
* @param x the x coordinate
|
|
* @param y the y coordinate
|
|
* @return false; the line does not contain points
|
|
*/
|
|
public boolean contains(double x, double y)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Test if a point is contained inside the line. Since a line has no area,
|
|
* this returns false.
|
|
*
|
|
* @param p the point
|
|
* @return false; the line does not contain points
|
|
*/
|
|
public boolean contains(Point2D p)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Tests if this line intersects the interior of the specified rectangle.
|
|
*
|
|
* @param x the x coordinate of the rectangle
|
|
* @param y the y coordinate of the rectangle
|
|
* @param w the width of the rectangle
|
|
* @param h the height of the rectangle
|
|
* @return true if the line intersects the rectangle
|
|
*/
|
|
public boolean intersects(double x, double y, double w, double h)
|
|
{
|
|
if (w <= 0 || h <= 0)
|
|
return false;
|
|
double x1 = getX1();
|
|
double y1 = getY1();
|
|
double x2 = getX2();
|
|
double y2 = getY2();
|
|
|
|
if (x1 >= x && x1 <= x + w && y1 >= y && y1 <= y + h)
|
|
return true;
|
|
if (x2 >= x && x2 <= x + w && y2 >= y && y2 <= y + h)
|
|
return true;
|
|
|
|
double x3 = x + w;
|
|
double y3 = y + h;
|
|
|
|
return (linesIntersect(x1, y1, x2, y2, x, y, x, y3)
|
|
|| linesIntersect(x1, y1, x2, y2, x, y3, x3, y3)
|
|
|| linesIntersect(x1, y1, x2, y2, x3, y3, x3, y)
|
|
|| linesIntersect(x1, y1, x2, y2, x3, y, x, y));
|
|
}
|
|
|
|
/**
|
|
* Tests if this line intersects the interior of the specified rectangle.
|
|
*
|
|
* @param r the rectangle
|
|
* @return true if the line intersects the rectangle
|
|
* @throws NullPointerException if r is null
|
|
*/
|
|
public boolean intersects(Rectangle2D r)
|
|
{
|
|
return intersects(r.getX(), r.getY(), r.getWidth(), r.getHeight());
|
|
}
|
|
|
|
/**
|
|
* Tests if the line contains a rectangle. Since lines have no area, this
|
|
* always returns false.
|
|
*
|
|
* @param x the x coordinate of the rectangle
|
|
* @param y the y coordinate of the rectangle
|
|
* @param w the width of the rectangle
|
|
* @param h the height of the rectangle
|
|
* @return false; the line does not contain points
|
|
*/
|
|
public boolean contains(double x, double y, double w, double h)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Tests if the line contains a rectangle. Since lines have no area, this
|
|
* always returns false.
|
|
*
|
|
* @param r the rectangle
|
|
* @return false; the line does not contain points
|
|
*/
|
|
public boolean contains(Rectangle2D r)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Gets a bounding box (not necessarily minimal) for this line.
|
|
*
|
|
* @return the integer bounding box
|
|
* @see #getBounds2D()
|
|
*/
|
|
public Rectangle getBounds()
|
|
{
|
|
return getBounds2D().getBounds();
|
|
}
|
|
|
|
/**
|
|
* Return a path iterator, possibly applying a transform on the result. This
|
|
* iterator is not threadsafe.
|
|
*
|
|
* @param at the transform, or null
|
|
* @return a new path iterator
|
|
*/
|
|
public PathIterator getPathIterator(final AffineTransform at)
|
|
{
|
|
return new PathIterator()
|
|
{
|
|
/** Current coordinate. */
|
|
private int current = 0;
|
|
|
|
public int getWindingRule()
|
|
{
|
|
return WIND_NON_ZERO;
|
|
}
|
|
|
|
public boolean isDone()
|
|
{
|
|
return current >= 2;
|
|
}
|
|
|
|
public void next()
|
|
{
|
|
current++;
|
|
}
|
|
|
|
public int currentSegment(float[] coords)
|
|
{
|
|
int result;
|
|
switch (current)
|
|
{
|
|
case 0:
|
|
coords[0] = (float) getX1();
|
|
coords[1] = (float) getY1();
|
|
result = SEG_MOVETO;
|
|
break;
|
|
case 1:
|
|
coords[0] = (float) getX2();
|
|
coords[1] = (float) getY2();
|
|
result = SEG_LINETO;
|
|
break;
|
|
default:
|
|
throw new NoSuchElementException("line iterator out of bounds");
|
|
}
|
|
if (at != null)
|
|
at.transform(coords, 0, coords, 0, 1);
|
|
return result;
|
|
}
|
|
|
|
public int currentSegment(double[] coords)
|
|
{
|
|
int result;
|
|
switch (current)
|
|
{
|
|
case 0:
|
|
coords[0] = getX1();
|
|
coords[1] = getY1();
|
|
result = SEG_MOVETO;
|
|
break;
|
|
case 1:
|
|
coords[0] = getX2();
|
|
coords[1] = getY2();
|
|
result = SEG_LINETO;
|
|
break;
|
|
default:
|
|
throw new NoSuchElementException("line iterator out of bounds");
|
|
}
|
|
if (at != null)
|
|
at.transform(coords, 0, coords, 0, 1);
|
|
return result;
|
|
}
|
|
};
|
|
}
|
|
|
|
/**
|
|
* Return a flat path iterator, possibly applying a transform on the result.
|
|
* This iterator is not threadsafe.
|
|
*
|
|
* @param at the transform, or null
|
|
* @param flatness ignored, since lines are already flat
|
|
* @return a new path iterator
|
|
* @see #getPathIterator(AffineTransform)
|
|
*/
|
|
public PathIterator getPathIterator(AffineTransform at, double flatness)
|
|
{
|
|
return getPathIterator(at);
|
|
}
|
|
|
|
/**
|
|
* Create a new line of the same run-time type with the same contents as
|
|
* this one.
|
|
*
|
|
* @return the clone
|
|
*
|
|
* @exception OutOfMemoryError If there is not enough memory available.
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public Object clone()
|
|
{
|
|
try
|
|
{
|
|
return super.clone();
|
|
}
|
|
catch (CloneNotSupportedException e)
|
|
{
|
|
throw (Error) new InternalError().initCause(e); // Impossible
|
|
}
|
|
}
|
|
|
|
/**
|
|
* This class defines a point in <code>double</code> precision.
|
|
*
|
|
* @author Eric Blake (ebb9@email.byu.edu)
|
|
* @since 1.2
|
|
* @status updated to 1.4
|
|
*/
|
|
public static class Double extends Line2D
|
|
{
|
|
/** The x coordinate of the first point. */
|
|
public double x1;
|
|
|
|
/** The y coordinate of the first point. */
|
|
public double y1;
|
|
|
|
/** The x coordinate of the second point. */
|
|
public double x2;
|
|
|
|
/** The y coordinate of the second point. */
|
|
public double y2;
|
|
|
|
/**
|
|
* Construct the line segment (0,0)->(0,0).
|
|
*/
|
|
public Double()
|
|
{
|
|
}
|
|
|
|
/**
|
|
* Construct the line segment with the specified points.
|
|
*
|
|
* @param x1 the x coordinate of the first point
|
|
* @param y1 the y coordinate of the first point
|
|
* @param x2 the x coordinate of the second point
|
|
* @param y2 the y coordinate of the second point
|
|
*/
|
|
public Double(double x1, double y1, double x2, double y2)
|
|
{
|
|
this.x1 = x1;
|
|
this.y1 = y1;
|
|
this.x2 = x2;
|
|
this.y2 = y2;
|
|
}
|
|
|
|
/**
|
|
* Construct the line segment with the specified points.
|
|
*
|
|
* @param p1 the first point
|
|
* @param p2 the second point
|
|
* @throws NullPointerException if either point is null
|
|
*/
|
|
public Double(Point2D p1, Point2D p2)
|
|
{
|
|
x1 = p1.getX();
|
|
y1 = p1.getY();
|
|
x2 = p2.getX();
|
|
y2 = p2.getY();
|
|
}
|
|
|
|
/**
|
|
* Return the x coordinate of the first point.
|
|
*
|
|
* @return the value of x1
|
|
*/
|
|
public double getX1()
|
|
{
|
|
return x1;
|
|
}
|
|
|
|
/**
|
|
* Return the y coordinate of the first point.
|
|
*
|
|
* @return the value of y1
|
|
*/
|
|
public double getY1()
|
|
{
|
|
return y1;
|
|
}
|
|
|
|
/**
|
|
* Return the first point.
|
|
*
|
|
* @return the point (x1,y1)
|
|
*/
|
|
public Point2D getP1()
|
|
{
|
|
return new Point2D.Double(x1, y1);
|
|
}
|
|
|
|
/**
|
|
* Return the x coordinate of the second point.
|
|
*
|
|
* @return the value of x2
|
|
*/
|
|
public double getX2()
|
|
{
|
|
return x2;
|
|
}
|
|
|
|
/**
|
|
* Return the y coordinate of the second point.
|
|
*
|
|
* @return the value of y2
|
|
*/
|
|
public double getY2()
|
|
{
|
|
return y2;
|
|
}
|
|
|
|
/**
|
|
* Return the second point.
|
|
*
|
|
* @return the point (x2,y2)
|
|
*/
|
|
public Point2D getP2()
|
|
{
|
|
return new Point2D.Double(x2, y2);
|
|
}
|
|
|
|
/**
|
|
* Set this line to the given points.
|
|
*
|
|
* @param x1 the new x coordinate of the first point
|
|
* @param y1 the new y coordinate of the first point
|
|
* @param x2 the new x coordinate of the second point
|
|
* @param y2 the new y coordinate of the second point
|
|
*/
|
|
public void setLine(double x1, double y1, double x2, double y2)
|
|
{
|
|
this.x1 = x1;
|
|
this.y1 = y1;
|
|
this.x2 = x2;
|
|
this.y2 = y2;
|
|
}
|
|
|
|
/**
|
|
* Return the exact bounds of this line segment.
|
|
*
|
|
* @return the bounding box
|
|
*/
|
|
public Rectangle2D getBounds2D()
|
|
{
|
|
double x = Math.min(x1, x2);
|
|
double y = Math.min(y1, y2);
|
|
double w = Math.abs(x1 - x2);
|
|
double h = Math.abs(y1 - y2);
|
|
return new Rectangle2D.Double(x, y, w, h);
|
|
}
|
|
} // class Double
|
|
|
|
/**
|
|
* This class defines a point in <code>float</code> precision.
|
|
*
|
|
* @author Eric Blake (ebb9@email.byu.edu)
|
|
* @since 1.2
|
|
* @status updated to 1.4
|
|
*/
|
|
public static class Float extends Line2D
|
|
{
|
|
/** The x coordinate of the first point. */
|
|
public float x1;
|
|
|
|
/** The y coordinate of the first point. */
|
|
public float y1;
|
|
|
|
/** The x coordinate of the second point. */
|
|
public float x2;
|
|
|
|
/** The y coordinate of the second point. */
|
|
public float y2;
|
|
|
|
/**
|
|
* Construct the line segment (0,0)->(0,0).
|
|
*/
|
|
public Float()
|
|
{
|
|
}
|
|
|
|
/**
|
|
* Construct the line segment with the specified points.
|
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*
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* @param x1 the x coordinate of the first point
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* @param y1 the y coordinate of the first point
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* @param x2 the x coordinate of the second point
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* @param y2 the y coordinate of the second point
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*/
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public Float(float x1, float y1, float x2, float y2)
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{
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this.x1 = x1;
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this.y1 = y1;
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this.x2 = x2;
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this.y2 = y2;
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}
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/**
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* Construct the line segment with the specified points.
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*
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* @param p1 the first point
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* @param p2 the second point
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* @throws NullPointerException if either point is null
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*/
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public Float(Point2D p1, Point2D p2)
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{
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x1 = (float) p1.getX();
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y1 = (float) p1.getY();
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x2 = (float) p2.getX();
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y2 = (float) p2.getY();
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}
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/**
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* Return the x coordinate of the first point.
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*
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* @return the value of x1
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*/
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public double getX1()
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{
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return x1;
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}
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/**
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* Return the y coordinate of the first point.
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*
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* @return the value of y1
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*/
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public double getY1()
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{
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return y1;
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}
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/**
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* Return the first point.
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*
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* @return the point (x1,y1)
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*/
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public Point2D getP1()
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{
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return new Point2D.Float(x1, y1);
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}
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/**
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* Return the x coordinate of the second point.
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*
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* @return the value of x2
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*/
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public double getX2()
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{
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return x2;
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}
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/**
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* Return the y coordinate of the second point.
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*
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* @return the value of y2
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*/
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public double getY2()
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{
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return y2;
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}
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/**
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* Return the second point.
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*
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* @return the point (x2,y2)
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*/
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public Point2D getP2()
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{
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return new Point2D.Float(x2, y2);
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}
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/**
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* Set this line to the given points.
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*
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* @param x1 the new x coordinate of the first point
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* @param y1 the new y coordinate of the first point
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* @param x2 the new x coordinate of the second point
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* @param y2 the new y coordinate of the second point
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*/
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public void setLine(double x1, double y1, double x2, double y2)
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{
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this.x1 = (float) x1;
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this.y1 = (float) y1;
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this.x2 = (float) x2;
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this.y2 = (float) y2;
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}
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|
|
/**
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|
* Set this line to the given points.
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|
*
|
|
* @param x1 the new x coordinate of the first point
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|
* @param y1 the new y coordinate of the first point
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|
* @param x2 the new x coordinate of the second point
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|
* @param y2 the new y coordinate of the second point
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*/
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public void setLine(float x1, float y1, float x2, float y2)
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|
{
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|
this.x1 = x1;
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this.y1 = y1;
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|
this.x2 = x2;
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|
this.y2 = y2;
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}
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|
|
|
/**
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|
* Return the exact bounds of this line segment.
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|
*
|
|
* @return the bounding box
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|
*/
|
|
public Rectangle2D getBounds2D()
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|
{
|
|
float x = Math.min(x1, x2);
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|
float y = Math.min(y1, y2);
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|
float w = Math.abs(x1 - x2);
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|
float h = Math.abs(y1 - y2);
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|
return new Rectangle2D.Float(x, y, w, h);
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|
}
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} // class Float
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} // class Line2D
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