ECS System WIP

registry/NameHash.h

@@ -0,0 +1,41 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string_view>
+
+constexpr uint64_t FNV1A_OFFSET_BASIS_64 = 14695981039346656037ull;
+constexpr uint64_t FNV1A_PRIME_64 = 1099511628211ull;
+
+constexpr uint64_t HashLiteral(const char* str, std::size_t len) noexcept
+{
+    uint64_t hash = FNV1A_OFFSET_BASIS_64;
+    for (std::size_t i = 0; i < len; ++i)
+    {
+        hash ^= static_cast<unsigned char>(str[i]);
+        hash *= FNV1A_PRIME_64;
+    }
+    return hash;
+}
+
+constexpr uint64_t HashLiteral(const char* str) noexcept
+{
+    uint64_t hash = FNV1A_OFFSET_BASIS_64;
+    while (*str)
+    {
+        hash ^= static_cast<unsigned char>(*str++);
+        hash *= FNV1A_PRIME_64;
+    }
+    return hash;
+}
+
+inline uint64_t HashRuntime(std::string_view str) noexcept
+{
+    uint64_t hash = FNV1A_OFFSET_BASIS_64;
+    for (char c : str)
+    {
+        hash ^= static_cast<unsigned char>(c);
+        hash *= FNV1A_PRIME_64;
+    }
+    return hash;
+}