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d95794ec8a
As many open source projects have started doing it, we're removing the current year from the copyright notice, so that we don't need to bump it every year. It seems like only the first year of publication is technically relevant for copyright notices, and even that seems to be something that many companies stopped listing altogether (in a version controlled codebase, the commits are a much better source of date of publication than a hardcoded copyright statement). We also now list Godot Engine contributors first as we're collectively the current maintainers of the project, and we clarify that the "exclusive" copyright of the co-founders covers the timespan before opensourcing (their further contributions are included as part of Godot Engine contributors). Also fixed "cf." Frenchism - it's meant as "refer to / see".
521 lines
16 KiB
C++
521 lines
16 KiB
C++
/**************************************************************************/
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/* hashfuncs.h */
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/**************************************************************************/
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/* This file is part of: */
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/* GODOT ENGINE */
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/* https://godotengine.org */
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/**************************************************************************/
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/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
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/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
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/* */
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/* Permission is hereby granted, free of charge, to any person obtaining */
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/* a copy of this software and associated documentation files (the */
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/* "Software"), to deal in the Software without restriction, including */
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/* without limitation the rights to use, copy, modify, merge, publish, */
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/* distribute, sublicense, and/or sell copies of the Software, and to */
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/* permit persons to whom the Software is furnished to do so, subject to */
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/* the following conditions: */
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/* */
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/* The above copyright notice and this permission notice shall be */
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/* included in all copies or substantial portions of the Software. */
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/* */
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/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
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/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
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/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
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/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
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/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
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/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
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/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
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/**************************************************************************/
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#ifndef HASHFUNCS_H
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#define HASHFUNCS_H
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#include "core/math/aabb.h"
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#include "core/math/math_defs.h"
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#include "core/math/math_funcs.h"
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#include "core/math/rect2.h"
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#include "core/math/rect2i.h"
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#include "core/math/vector2.h"
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#include "core/math/vector2i.h"
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#include "core/math/vector3.h"
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#include "core/math/vector3i.h"
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#include "core/math/vector4.h"
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#include "core/math/vector4i.h"
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#include "core/object/object_id.h"
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#include "core/string/node_path.h"
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#include "core/string/string_name.h"
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#include "core/string/ustring.h"
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#include "core/templates/rid.h"
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#include "core/typedefs.h"
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/**
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* Hashing functions
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*/
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/**
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* DJB2 Hash function
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* @param C String
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* @return 32-bits hashcode
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*/
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static _FORCE_INLINE_ uint32_t hash_djb2(const char *p_cstr) {
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const unsigned char *chr = (const unsigned char *)p_cstr;
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uint32_t hash = 5381;
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uint32_t c = *chr++;
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while (c) {
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hash = ((hash << 5) + hash) ^ c; /* hash * 33 ^ c */
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c = *chr++;
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}
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return hash;
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}
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static _FORCE_INLINE_ uint32_t hash_djb2_buffer(const uint8_t *p_buff, int p_len, uint32_t p_prev = 5381) {
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uint32_t hash = p_prev;
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for (int i = 0; i < p_len; i++) {
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hash = ((hash << 5) + hash) ^ p_buff[i]; /* hash * 33 + c */
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}
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return hash;
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}
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static _FORCE_INLINE_ uint32_t hash_djb2_one_32(uint32_t p_in, uint32_t p_prev = 5381) {
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return ((p_prev << 5) + p_prev) ^ p_in;
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}
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/**
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* Thomas Wang's 64-bit to 32-bit Hash function:
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* https://web.archive.org/web/20071223173210/https:/www.concentric.net/~Ttwang/tech/inthash.htm
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*
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* @param p_int - 64-bit unsigned integer key to be hashed
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* @return unsigned 32-bit value representing hashcode
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*/
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static _FORCE_INLINE_ uint32_t hash_one_uint64(const uint64_t p_int) {
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uint64_t v = p_int;
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v = (~v) + (v << 18); // v = (v << 18) - v - 1;
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v = v ^ (v >> 31);
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v = v * 21; // v = (v + (v << 2)) + (v << 4);
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v = v ^ (v >> 11);
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v = v + (v << 6);
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v = v ^ (v >> 22);
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return uint32_t(v);
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}
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#define HASH_MURMUR3_SEED 0x7F07C65
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// Murmurhash3 32-bit version.
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// All MurmurHash versions are public domain software, and the author disclaims all copyright to their code.
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static _FORCE_INLINE_ uint32_t hash_murmur3_one_32(uint32_t p_in, uint32_t p_seed = HASH_MURMUR3_SEED) {
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p_in *= 0xcc9e2d51;
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p_in = (p_in << 15) | (p_in >> 17);
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p_in *= 0x1b873593;
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p_seed ^= p_in;
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p_seed = (p_seed << 13) | (p_seed >> 19);
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p_seed = p_seed * 5 + 0xe6546b64;
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return p_seed;
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}
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static _FORCE_INLINE_ uint32_t hash_murmur3_one_float(float p_in, uint32_t p_seed = HASH_MURMUR3_SEED) {
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union {
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float f;
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uint32_t i;
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} u;
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// Normalize +/- 0.0 and NaN values so they hash the same.
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if (p_in == 0.0f) {
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u.f = 0.0;
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} else if (Math::is_nan(p_in)) {
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u.f = NAN;
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} else {
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u.f = p_in;
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}
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return hash_murmur3_one_32(u.i, p_seed);
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}
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static _FORCE_INLINE_ uint32_t hash_murmur3_one_64(uint64_t p_in, uint32_t p_seed = HASH_MURMUR3_SEED) {
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p_seed = hash_murmur3_one_32(p_in & 0xFFFFFFFF, p_seed);
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return hash_murmur3_one_32(p_in >> 32, p_seed);
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}
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static _FORCE_INLINE_ uint32_t hash_murmur3_one_double(double p_in, uint32_t p_seed = HASH_MURMUR3_SEED) {
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union {
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double d;
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uint64_t i;
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} u;
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// Normalize +/- 0.0 and NaN values so they hash the same.
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if (p_in == 0.0f) {
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u.d = 0.0;
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} else if (Math::is_nan(p_in)) {
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u.d = NAN;
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} else {
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u.d = p_in;
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}
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return hash_murmur3_one_64(u.i, p_seed);
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}
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static _FORCE_INLINE_ uint32_t hash_murmur3_one_real(real_t p_in, uint32_t p_seed = HASH_MURMUR3_SEED) {
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#ifdef REAL_T_IS_DOUBLE
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return hash_murmur3_one_double(p_in, p_seed);
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#else
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return hash_murmur3_one_float(p_in, p_seed);
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#endif
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}
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static _FORCE_INLINE_ uint32_t hash_rotl32(uint32_t x, int8_t r) {
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return (x << r) | (x >> (32 - r));
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}
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static _FORCE_INLINE_ uint32_t hash_fmix32(uint32_t h) {
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h ^= h >> 16;
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h *= 0x85ebca6b;
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h ^= h >> 13;
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h *= 0xc2b2ae35;
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h ^= h >> 16;
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return h;
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}
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static _FORCE_INLINE_ uint32_t hash_murmur3_buffer(const void *key, int length, const uint32_t seed = HASH_MURMUR3_SEED) {
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// Although not required, this is a random prime number.
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const uint8_t *data = (const uint8_t *)key;
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const int nblocks = length / 4;
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uint32_t h1 = seed;
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const uint32_t c1 = 0xcc9e2d51;
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const uint32_t c2 = 0x1b873593;
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const uint32_t *blocks = (const uint32_t *)(data + nblocks * 4);
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for (int i = -nblocks; i; i++) {
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uint32_t k1 = blocks[i];
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k1 *= c1;
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k1 = hash_rotl32(k1, 15);
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k1 *= c2;
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h1 ^= k1;
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h1 = hash_rotl32(h1, 13);
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h1 = h1 * 5 + 0xe6546b64;
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}
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const uint8_t *tail = (const uint8_t *)(data + nblocks * 4);
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uint32_t k1 = 0;
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switch (length & 3) {
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case 3:
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k1 ^= tail[2] << 16;
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[[fallthrough]];
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case 2:
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k1 ^= tail[1] << 8;
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[[fallthrough]];
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case 1:
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k1 ^= tail[0];
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k1 *= c1;
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k1 = hash_rotl32(k1, 15);
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k1 *= c2;
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h1 ^= k1;
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};
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// Finalize with additional bit mixing.
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h1 ^= length;
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return hash_fmix32(h1);
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}
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static _FORCE_INLINE_ uint32_t hash_djb2_one_float(double p_in, uint32_t p_prev = 5381) {
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union {
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double d;
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uint64_t i;
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} u;
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// Normalize +/- 0.0 and NaN values so they hash the same.
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if (p_in == 0.0f) {
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u.d = 0.0;
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} else if (Math::is_nan(p_in)) {
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u.d = NAN;
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} else {
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u.d = p_in;
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}
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return ((p_prev << 5) + p_prev) + hash_one_uint64(u.i);
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}
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template <class T>
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static _FORCE_INLINE_ uint32_t hash_make_uint32_t(T p_in) {
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union {
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T t;
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uint32_t _u32;
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} _u;
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_u._u32 = 0;
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_u.t = p_in;
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return _u._u32;
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}
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static _FORCE_INLINE_ uint64_t hash_djb2_one_float_64(double p_in, uint64_t p_prev = 5381) {
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union {
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double d;
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uint64_t i;
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} u;
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// Normalize +/- 0.0 and NaN values so they hash the same.
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if (p_in == 0.0f) {
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u.d = 0.0;
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} else if (Math::is_nan(p_in)) {
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u.d = NAN;
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} else {
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u.d = p_in;
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}
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return ((p_prev << 5) + p_prev) + u.i;
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}
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static _FORCE_INLINE_ uint64_t hash_djb2_one_64(uint64_t p_in, uint64_t p_prev = 5381) {
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return ((p_prev << 5) + p_prev) ^ p_in;
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}
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template <class T>
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static _FORCE_INLINE_ uint64_t hash_make_uint64_t(T p_in) {
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union {
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T t;
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uint64_t _u64;
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} _u;
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_u._u64 = 0; // in case p_in is smaller
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_u.t = p_in;
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return _u._u64;
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}
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template <class T>
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class Ref;
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struct HashMapHasherDefault {
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// Generic hash function for any type.
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template <class T>
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static _FORCE_INLINE_ uint32_t hash(const T *p_pointer) { return hash_one_uint64((uint64_t)p_pointer); }
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template <class T>
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static _FORCE_INLINE_ uint32_t hash(const Ref<T> &p_ref) { return hash_one_uint64((uint64_t)p_ref.operator->()); }
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static _FORCE_INLINE_ uint32_t hash(const String &p_string) { return p_string.hash(); }
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static _FORCE_INLINE_ uint32_t hash(const char *p_cstr) { return hash_djb2(p_cstr); }
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static _FORCE_INLINE_ uint32_t hash(const wchar_t p_wchar) { return hash_fmix32(p_wchar); }
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static _FORCE_INLINE_ uint32_t hash(const char16_t p_uchar) { return hash_fmix32(p_uchar); }
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static _FORCE_INLINE_ uint32_t hash(const char32_t p_uchar) { return hash_fmix32(p_uchar); }
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static _FORCE_INLINE_ uint32_t hash(const RID &p_rid) { return hash_one_uint64(p_rid.get_id()); }
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static _FORCE_INLINE_ uint32_t hash(const CharString &p_char_string) { return hash_djb2(p_char_string.ptr()); }
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static _FORCE_INLINE_ uint32_t hash(const StringName &p_string_name) { return p_string_name.hash(); }
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static _FORCE_INLINE_ uint32_t hash(const NodePath &p_path) { return p_path.hash(); }
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static _FORCE_INLINE_ uint32_t hash(const ObjectID &p_id) { return hash_one_uint64(p_id); }
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static _FORCE_INLINE_ uint32_t hash(const uint64_t p_int) { return hash_one_uint64(p_int); }
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static _FORCE_INLINE_ uint32_t hash(const int64_t p_int) { return hash_one_uint64(p_int); }
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static _FORCE_INLINE_ uint32_t hash(const float p_float) { return hash_murmur3_one_float(p_float); }
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static _FORCE_INLINE_ uint32_t hash(const double p_double) { return hash_murmur3_one_double(p_double); }
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static _FORCE_INLINE_ uint32_t hash(const uint32_t p_int) { return hash_fmix32(p_int); }
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static _FORCE_INLINE_ uint32_t hash(const int32_t p_int) { return hash_fmix32(p_int); }
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static _FORCE_INLINE_ uint32_t hash(const uint16_t p_int) { return hash_fmix32(p_int); }
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static _FORCE_INLINE_ uint32_t hash(const int16_t p_int) { return hash_fmix32(p_int); }
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static _FORCE_INLINE_ uint32_t hash(const uint8_t p_int) { return hash_fmix32(p_int); }
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static _FORCE_INLINE_ uint32_t hash(const int8_t p_int) { return hash_fmix32(p_int); }
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static _FORCE_INLINE_ uint32_t hash(const Vector2i &p_vec) {
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uint32_t h = hash_murmur3_one_32(p_vec.x);
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h = hash_murmur3_one_32(p_vec.y, h);
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return hash_fmix32(h);
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}
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static _FORCE_INLINE_ uint32_t hash(const Vector3i &p_vec) {
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uint32_t h = hash_murmur3_one_32(p_vec.x);
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h = hash_murmur3_one_32(p_vec.y, h);
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h = hash_murmur3_one_32(p_vec.z, h);
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return hash_fmix32(h);
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}
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static _FORCE_INLINE_ uint32_t hash(const Vector4i &p_vec) {
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uint32_t h = hash_murmur3_one_32(p_vec.x);
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h = hash_murmur3_one_32(p_vec.y, h);
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h = hash_murmur3_one_32(p_vec.z, h);
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h = hash_murmur3_one_32(p_vec.w, h);
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return hash_fmix32(h);
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}
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static _FORCE_INLINE_ uint32_t hash(const Vector2 &p_vec) {
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uint32_t h = hash_murmur3_one_real(p_vec.x);
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h = hash_murmur3_one_real(p_vec.y, h);
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return hash_fmix32(h);
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}
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static _FORCE_INLINE_ uint32_t hash(const Vector3 &p_vec) {
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uint32_t h = hash_murmur3_one_real(p_vec.x);
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h = hash_murmur3_one_real(p_vec.y, h);
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h = hash_murmur3_one_real(p_vec.z, h);
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return hash_fmix32(h);
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}
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static _FORCE_INLINE_ uint32_t hash(const Vector4 &p_vec) {
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uint32_t h = hash_murmur3_one_real(p_vec.x);
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h = hash_murmur3_one_real(p_vec.y, h);
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h = hash_murmur3_one_real(p_vec.z, h);
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h = hash_murmur3_one_real(p_vec.w, h);
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return hash_fmix32(h);
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}
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static _FORCE_INLINE_ uint32_t hash(const Rect2i &p_rect) {
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uint32_t h = hash_murmur3_one_32(p_rect.position.x);
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h = hash_murmur3_one_32(p_rect.position.y, h);
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h = hash_murmur3_one_32(p_rect.size.x, h);
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h = hash_murmur3_one_32(p_rect.size.y, h);
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return hash_fmix32(h);
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}
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static _FORCE_INLINE_ uint32_t hash(const Rect2 &p_rect) {
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uint32_t h = hash_murmur3_one_real(p_rect.position.x);
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h = hash_murmur3_one_real(p_rect.position.y, h);
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h = hash_murmur3_one_real(p_rect.size.x, h);
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h = hash_murmur3_one_real(p_rect.size.y, h);
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return hash_fmix32(h);
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}
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static _FORCE_INLINE_ uint32_t hash(const AABB &p_aabb) {
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uint32_t h = hash_murmur3_one_real(p_aabb.position.x);
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h = hash_murmur3_one_real(p_aabb.position.y, h);
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h = hash_murmur3_one_real(p_aabb.position.z, h);
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h = hash_murmur3_one_real(p_aabb.size.x, h);
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h = hash_murmur3_one_real(p_aabb.size.y, h);
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h = hash_murmur3_one_real(p_aabb.size.z, h);
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return hash_fmix32(h);
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}
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};
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template <typename T>
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struct HashMapComparatorDefault {
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static bool compare(const T &p_lhs, const T &p_rhs) {
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return p_lhs == p_rhs;
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}
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};
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template <>
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struct HashMapComparatorDefault<float> {
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static bool compare(const float &p_lhs, const float &p_rhs) {
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return (p_lhs == p_rhs) || (Math::is_nan(p_lhs) && Math::is_nan(p_rhs));
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}
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};
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template <>
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struct HashMapComparatorDefault<double> {
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static bool compare(const double &p_lhs, const double &p_rhs) {
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return (p_lhs == p_rhs) || (Math::is_nan(p_lhs) && Math::is_nan(p_rhs));
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}
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};
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template <>
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struct HashMapComparatorDefault<Vector2> {
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static bool compare(const Vector2 &p_lhs, const Vector2 &p_rhs) {
|
|
return ((p_lhs.x == p_rhs.x) || (Math::is_nan(p_lhs.x) && Math::is_nan(p_rhs.x))) && ((p_lhs.y == p_rhs.y) || (Math::is_nan(p_lhs.y) && Math::is_nan(p_rhs.y)));
|
|
}
|
|
};
|
|
|
|
template <>
|
|
struct HashMapComparatorDefault<Vector3> {
|
|
static bool compare(const Vector3 &p_lhs, const Vector3 &p_rhs) {
|
|
return ((p_lhs.x == p_rhs.x) || (Math::is_nan(p_lhs.x) && Math::is_nan(p_rhs.x))) && ((p_lhs.y == p_rhs.y) || (Math::is_nan(p_lhs.y) && Math::is_nan(p_rhs.y))) && ((p_lhs.z == p_rhs.z) || (Math::is_nan(p_lhs.z) && Math::is_nan(p_rhs.z)));
|
|
}
|
|
};
|
|
|
|
constexpr uint32_t HASH_TABLE_SIZE_MAX = 29;
|
|
|
|
const uint32_t hash_table_size_primes[HASH_TABLE_SIZE_MAX] = {
|
|
5,
|
|
13,
|
|
23,
|
|
47,
|
|
97,
|
|
193,
|
|
389,
|
|
769,
|
|
1543,
|
|
3079,
|
|
6151,
|
|
12289,
|
|
24593,
|
|
49157,
|
|
98317,
|
|
196613,
|
|
393241,
|
|
786433,
|
|
1572869,
|
|
3145739,
|
|
6291469,
|
|
12582917,
|
|
25165843,
|
|
50331653,
|
|
100663319,
|
|
201326611,
|
|
402653189,
|
|
805306457,
|
|
1610612741,
|
|
};
|
|
|
|
// Computed with elem_i = UINT64_C (0 x FFFFFFFF FFFFFFFF ) / d_i + 1, where d_i is the i-th element of the above array.
|
|
const uint64_t hash_table_size_primes_inv[HASH_TABLE_SIZE_MAX] = {
|
|
3689348814741910324,
|
|
1418980313362273202,
|
|
802032351030850071,
|
|
392483916461905354,
|
|
190172619316593316,
|
|
95578984837873325,
|
|
47420935922132524,
|
|
23987963684927896,
|
|
11955116055547344,
|
|
5991147799191151,
|
|
2998982941588287,
|
|
1501077717772769,
|
|
750081082979285,
|
|
375261795343686,
|
|
187625172388393,
|
|
93822606204624,
|
|
46909513691883,
|
|
23456218233098,
|
|
11728086747027,
|
|
5864041509391,
|
|
2932024948977,
|
|
1466014921160,
|
|
733007198436,
|
|
366503839517,
|
|
183251896093,
|
|
91625960335,
|
|
45812983922,
|
|
22906489714,
|
|
11453246088
|
|
};
|
|
|
|
/**
|
|
* Fastmod computes ( n mod d ) given the precomputed c much faster than n % d.
|
|
* The implementation of fastmod is based on the following paper by Daniel Lemire et al.
|
|
* Faster Remainder by Direct Computation: Applications to Compilers and Software Libraries
|
|
* https://arxiv.org/abs/1902.01961
|
|
*/
|
|
static _FORCE_INLINE_ uint32_t fastmod(const uint32_t n, const uint64_t c, const uint32_t d) {
|
|
#if defined(_MSC_VER)
|
|
// Returns the upper 64 bits of the product of two 64-bit unsigned integers.
|
|
// This intrinsic function is required since MSVC does not support unsigned 128-bit integers.
|
|
#if defined(_M_X64) || defined(_M_ARM64)
|
|
return __umulh(c * n, d);
|
|
#else
|
|
// Fallback to the slower method for 32-bit platforms.
|
|
return n % d;
|
|
#endif // _M_X64 || _M_ARM64
|
|
#else
|
|
#ifdef __SIZEOF_INT128__
|
|
// Prevent compiler warning, because we know what we are doing.
|
|
uint64_t lowbits = c * n;
|
|
__extension__ typedef unsigned __int128 uint128;
|
|
return static_cast<uint64_t>(((uint128)lowbits * d) >> 64);
|
|
#else
|
|
// Fallback to the slower method if no 128-bit unsigned integer type is available.
|
|
return n % d;
|
|
#endif // __SIZEOF_INT128__
|
|
#endif // _MSC_VER
|
|
}
|
|
|
|
#endif // HASHFUNCS_H
|