/** * Copyright (C) 2022 FalsePattern * All Rights Reserved * * The above copyright notice, this permission notice and the word "SNEED" * shall be included in all copies or substantial portions of the Software. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License 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 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 . */ package com.falsepattern.lib.compat; import com.falsepattern.lib.DeprecationDetails; import com.falsepattern.lib.util.MathUtil; import java.util.Random; /** * Alert: This class will be removed in 0.11, migrate to {@link MathUtil}! */ @Deprecated @DeprecationDetails(deprecatedSince = "0.10.0") public class MathHelper { /** * Though it looks like an array, this is really more like a mapping. Key (index of this array) is the upper 5 bits * of the result of multiplying a 32-bit unsigned integer by the B(2, 5) De Bruijn sequence 0x077CB531. Value * (value stored in the array) is the unique index (from the right) of the leftmost one-bit in a 32-bit unsigned * integer that can cause the upper 5 bits to get that value. Used for highly optimized "find the log-base-2 of * this number" calculations. */ private static final int[] multiplyDeBruijnBitPosition; private static final float[] SIN_TABLE = new float[65536]; static { for (int i = 0; i < 65536; ++i) { SIN_TABLE[i] = (float) Math.sin((double) i * Math.PI * 2.0D / 65536.0D); } multiplyDeBruijnBitPosition = new int[]{0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8, 31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9}; } /** * sin looked up in a table */ public static float sin(float a) { return SIN_TABLE[(int) (a * 10430.378F) & 65535]; } /** * cos looked up in the sin table with the appropriate offset */ public static float cos(float a) { return SIN_TABLE[(int) (a * 10430.378F + 16384.0F) & 65535]; } public static float sqrt_float(float a) { return (float) Math.sqrt(a); } public static float sqrt_double(double a) { return (float) Math.sqrt(a); } /** * Returns the greatest integer less than or equal to the float argument */ public static int floor_float(float a) { int i = (int) a; return a < (float) i ? i - 1 : i; } /** * returns par0 cast as an int, and no greater than Integer.MAX_VALUE-1024 */ public static int truncateDoubleToInt(double a) { return (int) (a + 1024.0D) - 1024; } /** * Returns the greatest integer less than or equal to the double argument */ public static int floor_double(double a) { int i = (int) a; return a < (double) i ? i - 1 : i; } /** * Long version of floor_double */ public static long floor_double_long(double a) { long i = (long) a; return a < (double) i ? i - 1L : i; } public static int absFloor(double a) { return (int) (a >= 0.0D ? a : -a + 1.0D); } public static float abs(float a) { return a >= 0.0F ? a : -a; } /** * Returns the unsigned value of an int. */ public static int abs_int(int a) { return a >= 0 ? a : -a; } public static int ceiling_float_int(float a) { int i = (int) a; return a > (float) i ? i + 1 : i; } public static int ceiling_double_int(double a) { int i = (int) a; return a > (double) i ? i + 1 : i; } /** * Returns the value of the first parameter, clamped to be within the lower and upper limits given by the second and * third parameters. */ public static int clamp_int(int a, int min, int max) { return a < min ? min : (Math.min(a, max)); } /** * Returns the value of the first parameter, clamped to be within the lower and upper limits given by the second and * third parameters */ public static float clamp_float(float a, float min, float max) { return a < min ? min : Math.min(a, max); } public static double clamp_double(double a, double min, double max) { return a < min ? min : Math.min(a, max); } public static double denormalizeClamp(double min, double max, double normalized) { return normalized < 0.0D ? min : (normalized > 1.0D ? max : min + (max - min) * normalized); } /** * Maximum of the absolute value of two numbers. */ public static double abs_max(double a, double b) { if (a < 0.0D) { a = -a; } if (b < 0.0D) { b = -b; } return Math.max(a, b); } /** * Buckets an integer with specifed bucket sizes. Args: i, bucketSize */ public static int bucketInt(int i, int bucketSize) { return i < 0 ? -((-i - 1) / bucketSize) - 1 : i / bucketSize; } /** * Tests if a string is null or of length zero */ public static boolean stringNullOrLengthZero(String str) { return str == null || str.length() == 0; } public static int getRandomIntegerInRange(Random rng, int min, int max) { return min >= max ? min : rng.nextInt(max - min + 1) + min; } public static float randomFloatClamp(Random rng, float min, float max) { return min >= max ? min : rng.nextFloat() * (max - min) + min; } public static double getRandomDoubleInRange(Random rng, double min, double max) { return min >= max ? min : rng.nextDouble() * (max - min) + min; } public static double average(long[] values) { long i = 0L; long[] along1 = values; int j = values.length; for (int k = 0; k < j; ++k) { long l = along1[k]; i += l; } return (double) i / (double) values.length; } /** * the angle is reduced to an angle between -180 and +180 by mod, and a 360 check */ public static float wrapAngleTo180_float(float angle) { angle %= 360.0F; if (angle >= 180.0F) { angle -= 360.0F; } if (angle < -180.0F) { angle += 360.0F; } return angle; } /** * the angle is reduced to an angle between -180 and +180 by mod, and a 360 check */ public static double wrapAngleTo180_double(double angle) { angle %= 360.0D; if (angle >= 180.0D) { angle -= 360.0D; } if (angle < -180.0D) { angle += 360.0D; } return angle; } /** * parses the string as integer or returns the second parameter if it fails */ public static int parseIntWithDefault(String str, int def) { int j = def; try { j = Integer.parseInt(str); } catch (Throwable throwable) { } return j; } /** * parses the string as integer or returns the second parameter if it fails. this value is capped to par2 */ public static int parseIntWithDefaultAndMax(String str, int def, int min) { int k = def; try { k = Integer.parseInt(str); } catch (Throwable throwable) { } if (k < min) { k = min; } return k; } /** * parses the string as double or returns the second parameter if it fails. */ public static double parseDoubleWithDefault(String str, double def) { double d1 = def; try { d1 = Double.parseDouble(str); } catch (Throwable ignored) { } return d1; } public static double parseDoubleWithDefaultAndMin(String str, double def, double min) { double d2 = def; try { d2 = Double.parseDouble(str); } catch (Throwable throwable) { } if (d2 < min) { d2 = min; } return d2; } /** * Returns the input value rounded up to the next highest power of two. */ public static int roundUpToPowerOfTwo(int a) { int j = a - 1; j |= j >> 1; j |= j >> 2; j |= j >> 4; j |= j >> 8; j |= j >> 16; return j + 1; } /** * Is the given value a power of two? (1, 2, 4, 8, 16, ...) */ private static boolean isPowerOfTwo(int a) { return a != 0 && (a & a - 1) == 0; } /** * Uses a B(2, 5) De Bruijn sequence and a lookup table to efficiently calculate the log-base-two of the given * value. Optimized for cases where the input value is a power-of-two. If the input value is not a power-of-two, * then subtract 1 from the return value. */ private static int calculateLogBaseTwoDeBruijn(int a) { a = isPowerOfTwo(a) ? a : roundUpToPowerOfTwo(a); return multiplyDeBruijnBitPosition[(int) ((long) a * 125613361L >> 27) & 31]; } /** * Efficiently calculates the floor of the base-2 log of an integer value. This is effectively the index of the * highest bit that is set. For example, if the number in binary is 0...100101, this will return 5. */ public static int calculateLogBaseTwo(int a) { /** * Uses a B(2, 5) De Bruijn sequence and a lookup table to efficiently calculate the log-base-two of the given * value. Optimized for cases where the input value is a power-of-two. If the input value is not a power-of- * two, then subtract 1 from the return value. */ return calculateLogBaseTwoDeBruijn(a) - (isPowerOfTwo(a) ? 0 : 1); } public static int roundUp(int a, int b) { if (b == 0) { return 0; } else { if (a < 0) { b *= -1; } int k = a % b; return k == 0 ? a : a + b - k; } } }