android/source/src/java/org/mozilla/gecko/util/FloatUtils.java

   1 /* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
   2  * This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 package org.mozilla.gecko.util;
   7
   8 import android.graphics.PointF;
   9
  10 public final class FloatUtils {
  11     private FloatUtils() {}
  12
  13     public static boolean fuzzyEquals(float a, float b) {
  14         return (Math.abs(a - b) < 1e-6);
  15     }
  16
  17     public static boolean fuzzyEquals(PointF a, PointF b) {
  18         return fuzzyEquals(a.x, b.x) && fuzzyEquals(a.y, b.y);
  19     }
  20
  21     /*
  22      * Returns the value that represents a linear transition between `from` and `to` at time `t`,
  23      * which is on the scale [0, 1). Thus with t = 0.0f, this returns `from`; with t = 1.0f, this
  24      * returns `to`; with t = 0.5f, this returns the value halfway from `from` to `to`.
  25      */
  26     public static float interpolate(float from, float to, float t) {
  27         return from + (to - from) * t;
  28     }
  29
  30     /**
  31      * Returns 'value', clamped so that it isn't any lower than 'low', and it
  32      * isn't any higher than 'high'.
  33      */
  34     public static float clamp(float value, float low, float high) {
  35         if (high < low) {
  36             throw new IllegalArgumentException(
  37                     "clamp called with invalid parameters (" + high + " < " + low + ")" );
  38         }
  39         return Math.max(low, Math.min(high, value));
  40     }
  41 }