bbradson
45 lines
1.2 KiB
C#
45 lines
1.2 KiB
C#
// Copyright (c) 2023 bradson
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// This Source Code Form is subject to the terms of the Mozilla Public
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// License, v. 2.0. If a copy of the MPL was not distributed with this
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// file, You can obtain one at https://mozilla.org/MPL/2.0/.
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using System.Runtime.CompilerServices;
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namespace FisheryLib.Utility;
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public static class FishMath
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{
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public const double PHI
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= 1.61803398874989484820458683436563811772030917980576286213544862270526046281890244970720720418939113748475;
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[MethodImpl(MethodImplOptions.AggressiveInlining)]
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public static int TrailingZeroCount(uint value)
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=> value == 0
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? 32
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: _trailingZeroCountDeBruijn[(int)(((value & unchecked(0 - value)) * 125613361) >> 27)];
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public static int NextPowerOfTwo(int value)
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{
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#if NETCORE
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return 1L << (63 - BitOperations.LeadingZeroCount(value));
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#else
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value--;
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value |= value >> 1;
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value |= value >> 2;
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value |= value >> 4;
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value |= value >> 8;
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value |= value >> 16;
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value++;
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return value;
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#endif
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}
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private static byte[] _trailingZeroCountDeBruijn
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=
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[
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0, 1, 28, 2, 29, 14, 24, 3, 30, 22,
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20, 15, 25, 17, 4, 8, 31, 27, 13, 23,
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21, 19, 16, 7, 26, 12, 18, 6, 11, 5,
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10, 9
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];
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} |