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Diffstat (limited to 'utils/MathUtils.java')
-rw-r--r-- | utils/MathUtils.java | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/utils/MathUtils.java b/utils/MathUtils.java new file mode 100644 index 0000000..5500855 --- /dev/null +++ b/utils/MathUtils.java @@ -0,0 +1,134 @@ +/* + * Copyright 2021 Google LLC + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +// This file is automatically generated. Do not modify it. + +package com.google.ux.material.libmonet.utils; + +/** Utility methods for mathematical operations. */ +public class MathUtils { + private MathUtils() {} + + /** + * The signum function. + * + * @return 1 if num > 0, -1 if num < 0, and 0 if num = 0 + */ + public static int signum(double num) { + if (num < 0) { + return -1; + } else if (num == 0) { + return 0; + } else { + return 1; + } + } + + /** + * The linear interpolation function. + * + * @return start if amount = 0 and stop if amount = 1 + */ + public static double lerp(double start, double stop, double amount) { + return (1.0 - amount) * start + amount * stop; + } + + /** + * Clamps an integer between two integers. + * + * @return input when min <= input <= max, and either min or max otherwise. + */ + public static int clampInt(int min, int max, int input) { + if (input < min) { + return min; + } else if (input > max) { + return max; + } + + return input; + } + + /** + * Clamps an integer between two floating-point numbers. + * + * @return input when min <= input <= max, and either min or max otherwise. + */ + public static double clampDouble(double min, double max, double input) { + if (input < min) { + return min; + } else if (input > max) { + return max; + } + + return input; + } + + /** + * Sanitizes a degree measure as an integer. + * + * @return a degree measure between 0 (inclusive) and 360 (exclusive). + */ + public static int sanitizeDegreesInt(int degrees) { + degrees = degrees % 360; + if (degrees < 0) { + degrees = degrees + 360; + } + return degrees; + } + + /** + * Sanitizes a degree measure as a floating-point number. + * + * @return a degree measure between 0.0 (inclusive) and 360.0 (exclusive). + */ + public static double sanitizeDegreesDouble(double degrees) { + degrees = degrees % 360.0; + if (degrees < 0) { + degrees = degrees + 360.0; + } + return degrees; + } + + /** + * Sign of direction change needed to travel from one angle to another. + * + * <p>For angles that are 180 degrees apart from each other, both directions have the same travel + * distance, so either direction is shortest. The value 1.0 is returned in this case. + * + * @param from The angle travel starts from, in degrees. + * @param to The angle travel ends at, in degrees. + * @return -1 if decreasing from leads to the shortest travel distance, 1 if increasing from leads + * to the shortest travel distance. + */ + public static double rotationDirection(double from, double to) { + double increasingDifference = sanitizeDegreesDouble(to - from); + return increasingDifference <= 180.0 ? 1.0 : -1.0; + } + + /** Distance of two points on a circle, represented using degrees. */ + public static double differenceDegrees(double a, double b) { + return 180.0 - Math.abs(Math.abs(a - b) - 180.0); + } + + /** Multiplies a 1x3 row vector with a 3x3 matrix. */ + public static double[] matrixMultiply(double[] row, double[][] matrix) { + double a = row[0] * matrix[0][0] + row[1] * matrix[0][1] + row[2] * matrix[0][2]; + double b = row[0] * matrix[1][0] + row[1] * matrix[1][1] + row[2] * matrix[1][2]; + double c = row[0] * matrix[2][0] + row[1] * matrix[2][1] + row[2] * matrix[2][2]; + return new double[] {a, b, c}; + } +} + |