diff -r 000000000000 -r 6474c204b198 mobile/android/base/util/FloatUtils.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mobile/android/base/util/FloatUtils.java Wed Dec 31 06:09:35 2014 +0100 @@ -0,0 +1,43 @@ +/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*- + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +package org.mozilla.gecko.util; + +import android.graphics.PointF; + +import java.lang.IllegalArgumentException; + +public final class FloatUtils { + private FloatUtils() {} + + public static boolean fuzzyEquals(float a, float b) { + return (Math.abs(a - b) < 1e-6); + } + + public static boolean fuzzyEquals(PointF a, PointF b) { + return fuzzyEquals(a.x, b.x) && fuzzyEquals(a.y, b.y); + } + + /* + * Returns the value that represents a linear transition between `from` and `to` at time `t`, + * which is on the scale [0, 1). Thus with t = 0.0f, this returns `from`; with t = 1.0f, this + * returns `to`; with t = 0.5f, this returns the value halfway from `from` to `to`. + */ + public static float interpolate(float from, float to, float t) { + return from + (to - from) * t; + } + + /** + * Returns 'value', clamped so that it isn't any lower than 'low', and it + * isn't any higher than 'high'. + */ + public static float clamp(float value, float low, float high) { + if (high < low) { + throw new IllegalArgumentException( + "clamp called with invalid parameters (" + high + " < " + low + ")" ); + } + return Math.max(low, Math.min(high, value)); + } +}