org.graphstream.ui.geom.Point2 Maven / Gradle / Ivy

/*
 * This file is part of GraphStream .
 * 
 * GraphStream is a library whose purpose is to handle static or dynamic
 * graph, create them from scratch, file or any source and display them.
 * 
 * This program is free software distributed under the terms of two licenses, the
 * CeCILL-C license that fits European law, and the GNU Lesser General Public
 * License. You can  use, modify and/ or redistribute the software under the terms
 * of the CeCILL-C license as circulated by CEA, CNRS and INRIA at the following
 * URL  or under the terms of the GNU LGPL as published by
 * the Free Software Foundation, either version 3 of the License, or (at your
 * option) any later version.
 * 
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see .
 * 
 * The fact that you are presently reading this means that you have had
 * knowledge of the CeCILL-C and LGPL licenses and that you accept their terms.
 */

/**
 * @since 2009-12-22
 * 
 * @author Antoine Dutot 
 * @author Guilhelm Savin 
 * @author Alex Bowen 
 * @author kitskub 
 * @author Hicham Brahimi 
 */
package org.graphstream.ui.geom;

/**
 * 2D point.
 * 
 * A Point2 is a 2D location in an affine space described by three values along
 * the X, and Y axes. This differs from the Vector3 and Vector4 classes in that
 * it is only 2D and has no vector arithmetic bound to it (to points cannot be
 * added, this would have no mathematical meaning).
 * 
 * @author Antoine Dutot
 * @since 20001121 creation
 * @version 0.1
 */
public class Point2 implements java.io.Serializable {
	// Attributes

	private static final long serialVersionUID = 965985679540486895L;

	/**
	 * X axis value.
	 */
	public double x;

	/**
	 * Y axis value.
	 */
	public double y;

	// Attributes -- Shared

	/**
	 * Specific point at (0,0).
	 */
	public static final Point2 NULL_POINT2 = new Point2(0, 0);

	// Constructors

	/**
	 * New 2D point at (0,0).
	 */
	public Point2() {
	}

	/**
	 * New 2D point at (x,y).
	 */
	public Point2(double x, double y) {
		set(x, y);
	}

	/**
	 * New copy of other.
	 */
	public Point2(Point2 other) {
		copy(other);
	}

	/**
	 * New 2D point at (x,y).
	 */
	public void make(double x, double y) {
		set(x, y);
	}

	// Accessors

	/**
	 * Are all components to zero?.
	 */
	public boolean isZero() {
		return (x == 0 && y == 0);
	}

	// /**
	// * Is other equal to this ?
	// */
	// public boolean
	// equals( const Point2 < double > & other ) const
	// {
	// return( x == other.x
	// and y == other.y
	// and z == other.z );
	// }

	/**
	 * Create a new point linear interpolation of this and other. The
	 * new point is located between this and other if
	 * factor is between 0 and 1 (0 yields this point, 1 yields the
	 * other point).
	 */
	public Point2 interpolate(Point2 other, double factor) {
		Point2 p = new Point2(x + ((other.x - x) * factor), y + ((other.y - y) * factor));

		return p;
	}

	/**
	 * Distance between this and other.
	 */
	public double distance(Point2 other) {
		double xx = other.x - x;
		double yy = other.y - y;
		return Math.abs(Math.sqrt((xx * xx) + (yy * yy)));
	}

	// Commands

	/**
	 * Make this a copy of other.
	 */
	public void copy(Point2 other) {
		x = other.x;
		y = other.y;
	}

	/**
	 * Like #moveTo().
	 */
	public void set(double x, double y) {
		this.x = x;
		this.y = y;
	}

	// Commands -- moving

	/**
	 * Move to absolute position (x,y).
	 */
	public void moveTo(double x, double y) {
		this.x = x;
		this.y = y;
	}

	/**
	 * Move of given vector (dx,dy).
	 */
	public void move(double dx, double dy) {
		this.x += dx;
		this.y += dy;
	}

	/**
	 * Move of given point p.
	 */
	public void move(Point2 p) {
		this.x += p.x;
		this.y += p.y;
	}

	/**
	 * Move horizontally of dx.
	 */
	public void moveX(double dx) {
		x += dx;
	}

	/**
	 * Move vertically of dy.
	 */
	public void moveY(double dy) {
		y += dy;
	}

	/**
	 * Scale of factor (sx,sy).
	 */
	public void scale(double sx, double sy) {
		x *= sx;
		y *= sy;
	}

	/**
	 * Scale by factor s.
	 */
	public void scale(Point2 s) {
		x *= s.x;
		y *= s.y;
	}

	/**
	 * Change only abscissa at absolute coordinate x.
	 */
	public void setX(double x) {
		this.x = x;
	}

	/**
	 * Change only ordinate at absolute coordinate y.
	 */
	public void setY(double y) {
		this.y = y;
	}

	/**
	 * Exchange the values of this and other.
	 */
	public void swap(Point2 other) {
		double t;

		if (other != this) {
			t = this.x;
			this.x = other.x;
			other.x = t;

			t = this.y;
			this.y = other.y;
			other.y = t;
		}
	}

	// Commands -- misc.

	@Override
	public String toString() {
		StringBuffer buf;

		buf = new StringBuffer("Point2[");

		buf.append(x);
		buf.append('|');
		buf.append(y);
		buf.append("]");

		return buf.toString();
	}

	@Override
	public boolean equals(Object o) {
		if (this == o) {
			return true;
		}
		if (o == null || getClass() != o.getClass()) {
			return false;
		}

		Point2 point2 = (Point2) o;

		if (Double.compare(point2.x, x) != 0) {
			return false;
		}
		if (Double.compare(point2.y, y) != 0) {
			return false;
		}

		return true;
	}

	@Override
	public int hashCode() {
		int result;
		long temp;
		temp = Double.doubleToLongBits(x);
		result = (int) (temp ^ (temp >>> 32));
		temp = Double.doubleToLongBits(y);
		result = 31 * result + (int) (temp ^ (temp >>> 32));
		return result;
	}
}