1 /*
   2  * Copyright (c) 2012, 2014, Oracle and/or its affiliates.
   3  * All rights reserved. Use is subject to license terms.
   4  *
   5  * This file is available and licensed under the following license:
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  *  - Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  *  - Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the distribution.
  16  *  - Neither the name of Oracle Corporation nor the names of its
  17  *    contributors may be used to endorse or promote products derived
  18  *    from this software without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  23  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  24  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  25  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  26  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  30  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  */
  32 package com.oracle.javafx.scenebuilder.kit.util;
  33 
  34 /**
  35  *
  36  */
  37 public class MathUtils {
  38 
  39     /**
  40      * Returns true if the two specified double values are approximately equals.
  41      * @param v1 first double to check
  42      * @param v2 second double to check
  43      * @return true if the two specified double values are approximately equals.
  44      */
  45     public static boolean equals(double v1, double v2) {
  46         return Math.abs(v1 - v2) < 0.0000001;
  47     }
  48 
  49     /**
  50      * Returns true if the two specified double values are equal with
  51      * the specified tolerance.
  52      *
  53      * @param v1 first double to check
  54      * @param v2 second double to check
  55      * @param tolerance a strictly positive value
  56      * @return true if the two specified double values are approximately equals.
  57      */
  58     public static boolean equals(double v1, double v2, double tolerance) {
  59         assert tolerance > 0.0;
  60         return Math.abs(v1 - v2) <= tolerance;
  61     }
  62 
  63 
  64     /**
  65      * Return the distance between two points.
  66      * @param x1 x coordinate of the first point
  67      * @param y1 y coordinate of the first point
  68      * @param x2 x coordinate of the second point
  69      * @param y2 x coordinate of the second point
  70      * @return the distance between (x1, y1) and (x2, y2)
  71      */
  72     public static double distance(double x1, double y1, double x2, double y2) {
  73         final double dx = x2 - x1;
  74         final double dy = y2 - y1;
  75         return Math.sqrt(dx * dx + dy * dy);
  76     }
  77 }