summaryrefslogtreecommitdiffstats
path: root/include/godot_cpp/templates/hashfuncs.hpp
diff options
context:
space:
mode:
authorbruvzg <7645683+bruvzg@users.noreply.github.com>2022-02-15 12:58:28 +0200
committerbruvzg <7645683+bruvzg@users.noreply.github.com>2022-02-18 21:07:53 +0200
commite36180f377d16d6ca63af15ef6f004c3f2114250 (patch)
tree473f3ddc634ff8af166e8bcab17d820b9c9fd4c2 /include/godot_cpp/templates/hashfuncs.hpp
parent6a464b53f1cba8f17f7d423cfe9b4b5a92c538d7 (diff)
downloadredot-cpp-e36180f377d16d6ca63af15ef6f004c3f2114250.tar.gz
Port a bunch of Godot container templates to GDExtension.
Diffstat (limited to 'include/godot_cpp/templates/hashfuncs.hpp')
-rw-r--r--include/godot_cpp/templates/hashfuncs.hpp191
1 files changed, 191 insertions, 0 deletions
diff --git a/include/godot_cpp/templates/hashfuncs.hpp b/include/godot_cpp/templates/hashfuncs.hpp
new file mode 100644
index 0000000..3b467db
--- /dev/null
+++ b/include/godot_cpp/templates/hashfuncs.hpp
@@ -0,0 +1,191 @@
+/*************************************************************************/
+/* hashfuncs.hpp */
+/*************************************************************************/
+/* This file is part of: */
+/* GODOT ENGINE */
+/* https://godotengine.org */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */
+/* */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the */
+/* "Software"), to deal in the Software without restriction, including */
+/* without limitation the rights to use, copy, modify, merge, publish, */
+/* distribute, sublicense, and/or sell copies of the Software, and to */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions: */
+/* */
+/* The above copyright notice and this permission notice shall be */
+/* included in all copies or substantial portions of the Software. */
+/* */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
+/*************************************************************************/
+
+#ifndef HASHFUNCS_HPP
+#define HASHFUNCS_HPP
+
+#include <godot_cpp/core/math.hpp>
+#include <godot_cpp/variant/rid.hpp>
+
+/**
+ * Hashing functions
+ */
+
+namespace godot {
+
+/**
+ * DJB2 Hash function
+ * @param C String
+ * @return 32-bits hashcode
+ */
+static inline uint32_t hash_djb2(const char *p_cstr) {
+ const unsigned char *chr = (const unsigned char *)p_cstr;
+ uint32_t hash = 5381;
+ uint32_t c;
+
+ while ((c = *chr++)) {
+ hash = ((hash << 5) + hash) + c; /* hash * 33 + c */
+ }
+
+ return hash;
+}
+
+static inline uint32_t hash_djb2_buffer(const uint8_t *p_buff, int p_len, uint32_t p_prev = 5381) {
+ uint32_t hash = p_prev;
+
+ for (int i = 0; i < p_len; i++) {
+ hash = ((hash << 5) + hash) + p_buff[i]; /* hash * 33 + c */
+ }
+
+ return hash;
+}
+
+static inline uint32_t hash_djb2_one_32(uint32_t p_in, uint32_t p_prev = 5381) {
+ return ((p_prev << 5) + p_prev) + p_in;
+}
+
+/**
+ * Thomas Wang's 64-bit to 32-bit Hash function:
+ * https://web.archive.org/web/20071223173210/https:/www.concentric.net/~Ttwang/tech/inthash.htm
+ *
+ * @param p_int - 64-bit unsigned integer key to be hashed
+ * @return unsigned 32-bit value representing hashcode
+ */
+static inline uint32_t hash_one_uint64(const uint64_t p_int) {
+ uint64_t v = p_int;
+ v = (~v) + (v << 18); // v = (v << 18) - v - 1;
+ v = v ^ (v >> 31);
+ v = v * 21; // v = (v + (v << 2)) + (v << 4);
+ v = v ^ (v >> 11);
+ v = v + (v << 6);
+ v = v ^ (v >> 22);
+ return uint32_t(v);
+}
+
+static inline uint32_t hash_djb2_one_float(double p_in, uint32_t p_prev = 5381) {
+ union {
+ double d;
+ uint64_t i;
+ } u;
+
+ // Normalize +/- 0.0 and NaN values so they hash the same.
+ if (p_in == 0.0f) {
+ u.d = 0.0;
+ } else if (std::isnan(p_in)) {
+ u.d = NAN;
+ } else {
+ u.d = p_in;
+ }
+
+ return ((p_prev << 5) + p_prev) + hash_one_uint64(u.i);
+}
+
+template <class T>
+static inline uint32_t make_uint32_t(T p_in) {
+ union {
+ T t;
+ uint32_t _u32;
+ } _u;
+ _u._u32 = 0;
+ _u.t = p_in;
+ return _u._u32;
+}
+
+static inline uint64_t hash_djb2_one_float_64(double p_in, uint64_t p_prev = 5381) {
+ union {
+ double d;
+ uint64_t i;
+ } u;
+
+ // Normalize +/- 0.0 and NaN values so they hash the same.
+ if (p_in == 0.0f) {
+ u.d = 0.0;
+ } else if (std::isnan(p_in)) {
+ u.d = NAN;
+ } else {
+ u.d = p_in;
+ }
+
+ return ((p_prev << 5) + p_prev) + u.i;
+}
+
+static inline uint64_t hash_djb2_one_64(uint64_t p_in, uint64_t p_prev = 5381) {
+ return ((p_prev << 5) + p_prev) + p_in;
+}
+
+template <class T>
+static inline uint64_t make_uint64_t(T p_in) {
+ union {
+ T t;
+ uint64_t _u64;
+ } _u;
+ _u._u64 = 0; // in case p_in is smaller
+
+ _u.t = p_in;
+ return _u._u64;
+}
+
+struct HashMapHasherDefault {
+ static _FORCE_INLINE_ uint32_t hash(const char *p_cstr) { return hash_djb2(p_cstr); }
+ static _FORCE_INLINE_ uint32_t hash(const uint64_t p_int) { return hash_one_uint64(p_int); }
+
+ static _FORCE_INLINE_ uint32_t hash(const int64_t p_int) { return hash(uint64_t(p_int)); }
+ static _FORCE_INLINE_ uint32_t hash(const float p_float) { return hash_djb2_one_float(p_float); }
+ static _FORCE_INLINE_ uint32_t hash(const double p_double) { return hash_djb2_one_float(p_double); }
+ static _FORCE_INLINE_ uint32_t hash(const uint32_t p_int) { return p_int; }
+ static _FORCE_INLINE_ uint32_t hash(const int32_t p_int) { return (uint32_t)p_int; }
+ static _FORCE_INLINE_ uint32_t hash(const uint16_t p_int) { return p_int; }
+ static _FORCE_INLINE_ uint32_t hash(const int16_t p_int) { return (uint32_t)p_int; }
+ static _FORCE_INLINE_ uint32_t hash(const uint8_t p_int) { return p_int; }
+ static _FORCE_INLINE_ uint32_t hash(const int8_t p_int) { return (uint32_t)p_int; }
+ static _FORCE_INLINE_ uint32_t hash(const wchar_t p_wchar) { return (uint32_t)p_wchar; }
+ static _FORCE_INLINE_ uint32_t hash(const char16_t p_uchar) { return (uint32_t)p_uchar; }
+ static _FORCE_INLINE_ uint32_t hash(const char32_t p_uchar) { return (uint32_t)p_uchar; }
+ static _FORCE_INLINE_ uint32_t hash(const RID &p_rid) { return hash_one_uint64(p_rid.get_id()); }
+};
+
+template <typename T>
+struct HashMapComparatorDefault {
+ static bool compare(const T &p_lhs, const T &p_rhs) {
+ return p_lhs == p_rhs;
+ }
+
+ bool compare(const float &p_lhs, const float &p_rhs) {
+ return (p_lhs == p_rhs) || (std::isnan(p_lhs) && std::isnan(p_rhs));
+ }
+
+ bool compare(const double &p_lhs, const double &p_rhs) {
+ return (p_lhs == p_rhs) || (std::isnan(p_lhs) && std::isnan(p_rhs));
+ }
+};
+
+} // namespace godot
+
+#endif // ! HASHFUNCS_HPP