diff --git a/include/fastgltf/util.hpp b/include/fastgltf/util.hpp index 1e866fc30..815c55029 100644 --- a/include/fastgltf/util.hpp +++ b/include/fastgltf/util.hpp @@ -136,40 +136,40 @@ #endif namespace fastgltf { - FASTGLTF_EXPORT template + FASTGLTF_EXPORT template #if FASTGLTF_HAS_CONCEPTS - requires std::is_enum_v + requires std::is_enum_v #endif - [[nodiscard]] FASTGLTF_INTRINSIC constexpr std::underlying_type_t to_underlying(T t) noexcept { + [[nodiscard]] FASTGLTF_INTRINSIC constexpr std::underlying_type_t to_underlying(T t) noexcept { #if !FASTGLTF_HAS_CONCEPTS - static_assert(std::is_enum_v, "to_underlying only works with enum types."); + static_assert(std::is_enum_v, "to_underlying only works with enum types."); #endif - return static_cast>(t); - } + return static_cast>(t); + } - FASTGLTF_EXPORT template + FASTGLTF_EXPORT template #if FASTGLTF_HAS_CONCEPTS - requires ((std::is_enum_v && std::integral>) || std::integral) && requires (T t, U u) { - { t & u } -> std::same_as; - } + requires ((std::is_enum_v && std::integral>) || std::integral) && requires (T t, U u) { + { t & u } -> std::same_as; + } #endif - [[nodiscard]] constexpr bool hasBit(T flags, U bit) { + [[nodiscard]] constexpr bool hasBit(T flags, U bit) { #if !FASTGLTF_HAS_CONCEPTS - static_assert((std::is_enum_v && std::is_integral_v>) || std::is_integral_v); + static_assert((std::is_enum_v && std::is_integral_v>) || std::is_integral_v); #endif - return (flags & bit) == bit; - } + return (flags & bit) == bit; + } - template - [[nodiscard]] constexpr T alignUp(T base, U alignment) { - static_assert(std::is_signed_v, "alignUp requires type U to be signed."); - return (base + alignment - 1) & -alignment; - } + template + [[nodiscard]] constexpr T alignUp(T base, U alignment) { + static_assert(std::is_signed_v, "alignUp requires type U to be signed."); + return (base + alignment - 1) & -alignment; + } - template - [[nodiscard]] constexpr T alignDown(T base, T alignment) { - return base - (base % alignment); - } + template + [[nodiscard]] constexpr T alignDown(T base, T alignment) { + return base - (base % alignment); + } FASTGLTF_EXPORT template #if FASTGLTF_HAS_CONCEPTS @@ -191,74 +191,74 @@ namespace fastgltf { return (a < b) ? a : b; } - template - [[noreturn]] constexpr void raise(A&&... args) { + template + [[noreturn]] constexpr void raise(A&&... args) { #ifdef __cpp_exceptions - throw T(std::forward(args)...); + throw T(std::forward(args)...); #else - std::abort(); -#endif - } - - /** - * Constants generated using 0x82f63b79u CRC poly. - */ - static constexpr std::array crcHashTable = {{ - 0x00000000, 0xf26b8303, 0xe13b70f7, 0x1350f3f4, 0xc79a971f, 0x35f1141c, 0x26a1e7e8, 0xd4ca64eb, - 0x8ad958cf, 0x78b2dbcc, 0x6be22838, 0x9989ab3b, 0x4d43cfd0, 0xbf284cd3, 0xac78bf27, 0x5e133c24, - 0x105ec76f, 0xe235446c, 0xf165b798, 0x030e349b, 0xd7c45070, 0x25afd373, 0x36ff2087, 0xc494a384, - 0x9a879fa0, 0x68ec1ca3, 0x7bbcef57, 0x89d76c54, 0x5d1d08bf, 0xaf768bbc, 0xbc267848, 0x4e4dfb4b, - 0x20bd8ede, 0xd2d60ddd, 0xc186fe29, 0x33ed7d2a, 0xe72719c1, 0x154c9ac2, 0x061c6936, 0xf477ea35, - 0xaa64d611, 0x580f5512, 0x4b5fa6e6, 0xb93425e5, 0x6dfe410e, 0x9f95c20d, 0x8cc531f9, 0x7eaeb2fa, - 0x30e349b1, 0xc288cab2, 0xd1d83946, 0x23b3ba45, 0xf779deae, 0x05125dad, 0x1642ae59, 0xe4292d5a, - 0xba3a117e, 0x4851927d, 0x5b016189, 0xa96ae28a, 0x7da08661, 0x8fcb0562, 0x9c9bf696, 0x6ef07595, - 0x417b1dbc, 0xb3109ebf, 0xa0406d4b, 0x522bee48, 0x86e18aa3, 0x748a09a0, 0x67dafa54, 0x95b17957, - 0xcba24573, 0x39c9c670, 0x2a993584, 0xd8f2b687, 0x0c38d26c, 0xfe53516f, 0xed03a29b, 0x1f682198, - 0x5125dad3, 0xa34e59d0, 0xb01eaa24, 0x42752927, 0x96bf4dcc, 0x64d4cecf, 0x77843d3b, 0x85efbe38, - 0xdbfc821c, 0x2997011f, 0x3ac7f2eb, 0xc8ac71e8, 0x1c661503, 0xee0d9600, 0xfd5d65f4, 0x0f36e6f7, - 0x61c69362, 0x93ad1061, 0x80fde395, 0x72966096, 0xa65c047d, 0x5437877e, 0x4767748a, 0xb50cf789, - 0xeb1fcbad, 0x197448ae, 0x0a24bb5a, 0xf84f3859, 0x2c855cb2, 0xdeeedfb1, 0xcdbe2c45, 0x3fd5af46, - 0x7198540d, 0x83f3d70e, 0x90a324fa, 0x62c8a7f9, 0xb602c312, 0x44694011, 0x5739b3e5, 0xa55230e6, - 0xfb410cc2, 0x092a8fc1, 0x1a7a7c35, 0xe811ff36, 0x3cdb9bdd, 0xceb018de, 0xdde0eb2a, 0x2f8b6829, - 0x82f63b78, 0x709db87b, 0x63cd4b8f, 0x91a6c88c, 0x456cac67, 0xb7072f64, 0xa457dc90, 0x563c5f93, - 0x082f63b7, 0xfa44e0b4, 0xe9141340, 0x1b7f9043, 0xcfb5f4a8, 0x3dde77ab, 0x2e8e845f, 0xdce5075c, - 0x92a8fc17, 0x60c37f14, 0x73938ce0, 0x81f80fe3, 0x55326b08, 0xa759e80b, 0xb4091bff, 0x466298fc, - 0x1871a4d8, 0xea1a27db, 0xf94ad42f, 0x0b21572c, 0xdfeb33c7, 0x2d80b0c4, 0x3ed04330, 0xccbbc033, - 0xa24bb5a6, 0x502036a5, 0x4370c551, 0xb11b4652, 0x65d122b9, 0x97baa1ba, 0x84ea524e, 0x7681d14d, - 0x2892ed69, 0xdaf96e6a, 0xc9a99d9e, 0x3bc21e9d, 0xef087a76, 0x1d63f975, 0x0e330a81, 0xfc588982, - 0xb21572c9, 0x407ef1ca, 0x532e023e, 0xa145813d, 0x758fe5d6, 0x87e466d5, 0x94b49521, 0x66df1622, - 0x38cc2a06, 0xcaa7a905, 0xd9f75af1, 0x2b9cd9f2, 0xff56bd19, 0x0d3d3e1a, 0x1e6dcdee, 0xec064eed, - 0xc38d26c4, 0x31e6a5c7, 0x22b65633, 0xd0ddd530, 0x0417b1db, 0xf67c32d8, 0xe52cc12c, 0x1747422f, - 0x49547e0b, 0xbb3ffd08, 0xa86f0efc, 0x5a048dff, 0x8ecee914, 0x7ca56a17, 0x6ff599e3, 0x9d9e1ae0, - 0xd3d3e1ab, 0x21b862a8, 0x32e8915c, 0xc083125f, 0x144976b4, 0xe622f5b7, 0xf5720643, 0x07198540, - 0x590ab964, 0xab613a67, 0xb831c993, 0x4a5a4a90, 0x9e902e7b, 0x6cfbad78, 0x7fab5e8c, 0x8dc0dd8f, - 0xe330a81a, 0x115b2b19, 0x020bd8ed, 0xf0605bee, 0x24aa3f05, 0xd6c1bc06, 0xc5914ff2, 0x37faccf1, - 0x69e9f0d5, 0x9b8273d6, 0x88d28022, 0x7ab90321, 0xae7367ca, 0x5c18e4c9, 0x4f48173d, 0xbd23943e, - 0xf36e6f75, 0x0105ec76, 0x12551f82, 0xe03e9c81, 0x34f4f86a, 0xc69f7b69, 0xd5cf889d, 0x27a40b9e, - 0x79b737ba, 0x8bdcb4b9, 0x988c474d, 0x6ae7c44e, 0xbe2da0a5, 0x4c4623a6, 0x5f16d052, 0xad7d5351, - }}; - - [[gnu::hot, gnu::const]] constexpr std::uint32_t crc32c(std::string_view str) noexcept { - std::uint32_t crc = 0; - for (auto c : str) - crc = (crc >> 8) ^ crcHashTable[(crc ^ static_cast(c)) & 0xff]; - return crc; - } - - [[gnu::hot, gnu::const]] constexpr std::uint32_t crc32c(const std::uint8_t* d, std::size_t len) noexcept { - std::uint32_t crc = 0; - for (std::size_t i = 0; i < len; ++i) - crc = (crc >> 8) ^ crcHashTable[(crc ^ d[i]) & 0xff]; - return crc; - } + std::abort(); +#endif + } + + /** + * Constants generated using 0x82f63b79u CRC poly. + */ + static constexpr std::array crcHashTable = {{ + 0x00000000, 0xf26b8303, 0xe13b70f7, 0x1350f3f4, 0xc79a971f, 0x35f1141c, 0x26a1e7e8, 0xd4ca64eb, + 0x8ad958cf, 0x78b2dbcc, 0x6be22838, 0x9989ab3b, 0x4d43cfd0, 0xbf284cd3, 0xac78bf27, 0x5e133c24, + 0x105ec76f, 0xe235446c, 0xf165b798, 0x030e349b, 0xd7c45070, 0x25afd373, 0x36ff2087, 0xc494a384, + 0x9a879fa0, 0x68ec1ca3, 0x7bbcef57, 0x89d76c54, 0x5d1d08bf, 0xaf768bbc, 0xbc267848, 0x4e4dfb4b, + 0x20bd8ede, 0xd2d60ddd, 0xc186fe29, 0x33ed7d2a, 0xe72719c1, 0x154c9ac2, 0x061c6936, 0xf477ea35, + 0xaa64d611, 0x580f5512, 0x4b5fa6e6, 0xb93425e5, 0x6dfe410e, 0x9f95c20d, 0x8cc531f9, 0x7eaeb2fa, + 0x30e349b1, 0xc288cab2, 0xd1d83946, 0x23b3ba45, 0xf779deae, 0x05125dad, 0x1642ae59, 0xe4292d5a, + 0xba3a117e, 0x4851927d, 0x5b016189, 0xa96ae28a, 0x7da08661, 0x8fcb0562, 0x9c9bf696, 0x6ef07595, + 0x417b1dbc, 0xb3109ebf, 0xa0406d4b, 0x522bee48, 0x86e18aa3, 0x748a09a0, 0x67dafa54, 0x95b17957, + 0xcba24573, 0x39c9c670, 0x2a993584, 0xd8f2b687, 0x0c38d26c, 0xfe53516f, 0xed03a29b, 0x1f682198, + 0x5125dad3, 0xa34e59d0, 0xb01eaa24, 0x42752927, 0x96bf4dcc, 0x64d4cecf, 0x77843d3b, 0x85efbe38, + 0xdbfc821c, 0x2997011f, 0x3ac7f2eb, 0xc8ac71e8, 0x1c661503, 0xee0d9600, 0xfd5d65f4, 0x0f36e6f7, + 0x61c69362, 0x93ad1061, 0x80fde395, 0x72966096, 0xa65c047d, 0x5437877e, 0x4767748a, 0xb50cf789, + 0xeb1fcbad, 0x197448ae, 0x0a24bb5a, 0xf84f3859, 0x2c855cb2, 0xdeeedfb1, 0xcdbe2c45, 0x3fd5af46, + 0x7198540d, 0x83f3d70e, 0x90a324fa, 0x62c8a7f9, 0xb602c312, 0x44694011, 0x5739b3e5, 0xa55230e6, + 0xfb410cc2, 0x092a8fc1, 0x1a7a7c35, 0xe811ff36, 0x3cdb9bdd, 0xceb018de, 0xdde0eb2a, 0x2f8b6829, + 0x82f63b78, 0x709db87b, 0x63cd4b8f, 0x91a6c88c, 0x456cac67, 0xb7072f64, 0xa457dc90, 0x563c5f93, + 0x082f63b7, 0xfa44e0b4, 0xe9141340, 0x1b7f9043, 0xcfb5f4a8, 0x3dde77ab, 0x2e8e845f, 0xdce5075c, + 0x92a8fc17, 0x60c37f14, 0x73938ce0, 0x81f80fe3, 0x55326b08, 0xa759e80b, 0xb4091bff, 0x466298fc, + 0x1871a4d8, 0xea1a27db, 0xf94ad42f, 0x0b21572c, 0xdfeb33c7, 0x2d80b0c4, 0x3ed04330, 0xccbbc033, + 0xa24bb5a6, 0x502036a5, 0x4370c551, 0xb11b4652, 0x65d122b9, 0x97baa1ba, 0x84ea524e, 0x7681d14d, + 0x2892ed69, 0xdaf96e6a, 0xc9a99d9e, 0x3bc21e9d, 0xef087a76, 0x1d63f975, 0x0e330a81, 0xfc588982, + 0xb21572c9, 0x407ef1ca, 0x532e023e, 0xa145813d, 0x758fe5d6, 0x87e466d5, 0x94b49521, 0x66df1622, + 0x38cc2a06, 0xcaa7a905, 0xd9f75af1, 0x2b9cd9f2, 0xff56bd19, 0x0d3d3e1a, 0x1e6dcdee, 0xec064eed, + 0xc38d26c4, 0x31e6a5c7, 0x22b65633, 0xd0ddd530, 0x0417b1db, 0xf67c32d8, 0xe52cc12c, 0x1747422f, + 0x49547e0b, 0xbb3ffd08, 0xa86f0efc, 0x5a048dff, 0x8ecee914, 0x7ca56a17, 0x6ff599e3, 0x9d9e1ae0, + 0xd3d3e1ab, 0x21b862a8, 0x32e8915c, 0xc083125f, 0x144976b4, 0xe622f5b7, 0xf5720643, 0x07198540, + 0x590ab964, 0xab613a67, 0xb831c993, 0x4a5a4a90, 0x9e902e7b, 0x6cfbad78, 0x7fab5e8c, 0x8dc0dd8f, + 0xe330a81a, 0x115b2b19, 0x020bd8ed, 0xf0605bee, 0x24aa3f05, 0xd6c1bc06, 0xc5914ff2, 0x37faccf1, + 0x69e9f0d5, 0x9b8273d6, 0x88d28022, 0x7ab90321, 0xae7367ca, 0x5c18e4c9, 0x4f48173d, 0xbd23943e, + 0xf36e6f75, 0x0105ec76, 0x12551f82, 0xe03e9c81, 0x34f4f86a, 0xc69f7b69, 0xd5cf889d, 0x27a40b9e, + 0x79b737ba, 0x8bdcb4b9, 0x988c474d, 0x6ae7c44e, 0xbe2da0a5, 0x4c4623a6, 0x5f16d052, 0xad7d5351, + }}; + + [[gnu::hot, gnu::const]] constexpr std::uint32_t crc32c(std::string_view str) noexcept { + std::uint32_t crc = 0; + for (auto c : str) + crc = (crc >> 8) ^ crcHashTable[(crc ^ static_cast(c)) & 0xff]; + return crc; + } + + [[gnu::hot, gnu::const]] constexpr std::uint32_t crc32c(const std::uint8_t* d, std::size_t len) noexcept { + std::uint32_t crc = 0; + for (std::size_t i = 0; i < len; ++i) + crc = (crc >> 8) ^ crcHashTable[(crc ^ d[i]) & 0xff]; + return crc; + } #if defined(FASTGLTF_IS_X86) - /** - * Variant of crc32 that uses SSE4.2 instructions to increase performance. Note that this does not - * check for availability of said instructions. - */ - [[gnu::hot, gnu::const]] std::uint32_t sse_crc32c(std::string_view str) noexcept; - [[gnu::hot, gnu::const]] std::uint32_t sse_crc32c(const std::uint8_t* d, std::size_t len) noexcept; + /** + * Variant of crc32 that uses SSE4.2 instructions to increase performance. Note that this does not + * check for availability of said instructions. + */ + [[gnu::hot, gnu::const]] std::uint32_t sse_crc32c(std::string_view str) noexcept; + [[gnu::hot, gnu::const]] std::uint32_t sse_crc32c(const std::uint8_t* d, std::size_t len) noexcept; #elif defined(FASTGLTF_IS_A64) && !defined(_MSC_VER) && !defined(__ANDROID__) // Both MSVC stdlib and Android NDK don't include the arm intrinsics. TODO: Find a workaround? #define FASTGLTF_ENABLE_ARMV8_CRC 1 @@ -266,70 +266,20 @@ namespace fastgltf { [[gnu::hot, gnu::const]] std::uint32_t armv8_crc32c(const std::uint8_t* d, std::size_t len) noexcept; #endif - /** - * Helper to force evaluation of constexpr functions at compile-time in C++17. One example of - * this is with crc32: force_consteval. No matter the context, this will - * always be evaluated to a constant. - */ - template - static constexpr auto force_consteval = V; - - /** - * Counts the leading zeros from starting the most significant bit. Returns a std::uint8_t as there - * can only ever be 2^6 zeros with 64-bit types. - */ - template -#if FASTGLTF_HAS_CONCEPTS - requires std::integral -#endif - [[gnu::const]] constexpr std::uint8_t clz(T value) { - static_assert(std::is_integral_v); -#if FASTGLTF_HAS_BIT - return static_cast(std::countl_zero(value)); -#else - // Very naive but working implementation of counting zero bits. Any sane compiler will - // optimise this away, like instead use the bsr x86 instruction. - if (value == 0) return sizeof(T) * 8; - std::uint8_t count = 0; - for (auto i = std::numeric_limits::digits - 1; i > 0; --i) { - if ((value >> i) == 1) { - return count; - } - ++count; - } - return count; -#endif - } - - template - [[gnu::const]] constexpr std::uint8_t popcount(T value) { - static_assert(std::is_integral_v); -#if FASTGLTF_HAS_BIT - return static_cast(std::popcount(value)); -#else - std::uint8_t bits = 0; - while (value) { - if (value & 1) - ++bits; - value >>= 1; - } - return bits; -#endif - } - - /** - * Essentially the same as std::same but it accepts multiple different types for U, - * checking if T is any of U... - */ - template - using is_any = std::disjunction...>; + /** + * Helper to force evaluation of constexpr functions at compile-time in C++17. One example of + * this is with crc32: force_consteval. No matter the context, this will + * always be evaluated to a constant. + */ + template + static constexpr auto force_consteval = V; - /** - * Simple function to check if the given string starts with a given set of characters. - */ - inline bool startsWith(std::string_view str, std::string_view search) { - return str.rfind(search, 0) == 0; - } + /** + * Essentially the same as std::same but it accepts multiple different types for U, + * checking if T is any of U... + */ + template + using is_any = std::disjunction...>; // Simple reimplementation of std::remove_cvref, which was only added in C++20. template @@ -368,40 +318,52 @@ namespace fastgltf { return std::visit(std::forward(visitor), std::forward(variant)); } - // For simple ops like &, |, +, - taking a left and right operand. + template + struct UniqueDeleter { + template + constexpr void operator()(T* t) const { + callback(t); + } + }; + + /** Allows the quick creation of a unique_ptr type that can take any function of the form void(T*) for its deleter */ + template + using deletable_unique_ptr = std::unique_ptr>; + + // For simple ops like &, |, +, - taking a left and right operand. #define FASTGLTF_ARITHMETIC_OP_TEMPLATE_MACRO(T1, T2, op) \ - FASTGLTF_EXPORT constexpr T1 operator op(const T1& a, const T2& b) noexcept { \ - static_assert(std::is_enum_v && std::is_enum_v); \ - return static_cast(to_underlying(a) op to_underlying(b)); \ - } + FASTGLTF_EXPORT constexpr T1 operator op(const T1& a, const T2& b) noexcept { \ + static_assert(std::is_enum_v && std::is_enum_v); \ + return static_cast(to_underlying(a) op to_underlying(b)); \ + } - // For any ops like |=, &=, +=, -= + // For any ops like |=, &=, +=, -= #define FASTGLTF_ASSIGNMENT_OP_TEMPLATE_MACRO(T1, T2, op) \ - FASTGLTF_EXPORT constexpr T1& operator op##=(T1& a, const T2& b) noexcept { \ - static_assert(std::is_enum_v && std::is_enum_v); \ - return a = static_cast(to_underlying(a) op to_underlying(b)), a; \ - } + FASTGLTF_EXPORT constexpr T1& operator op##=(T1& a, const T2& b) noexcept { \ + static_assert(std::is_enum_v && std::is_enum_v); \ + return a = static_cast(to_underlying(a) op to_underlying(b)), a; \ + } - // For unary +, unary -, and bitwise NOT + // For unary +, unary -, and bitwise NOT #define FASTGLTF_UNARY_OP_TEMPLATE_MACRO(T, op) \ - FASTGLTF_EXPORT constexpr T operator op(const T& a) noexcept { \ - static_assert(std::is_enum_v); \ - return static_cast(op to_underlying(a)); \ - } + FASTGLTF_EXPORT constexpr T operator op(const T& a) noexcept { \ + static_assert(std::is_enum_v); \ + return static_cast(op to_underlying(a)); \ + } #if FASTGLTF_CPP_20 && defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L #define FASTGLTF_CONSTEXPR_BITCAST 1 - template - [[nodiscard]] constexpr To bit_cast(const From& from) noexcept { - return std::bit_cast(from); - } + template + [[nodiscard]] constexpr To bit_cast(const From& from) noexcept { + return std::bit_cast(from); + } #elif (defined(__clang__) || __clang_major__ >= 9) || (defined(__GNUC__) && __GNUC__ >= 11) || FASTGLTF_HAS_BUILTIN(__builtin_bit_cast) #define FASTGLTF_CONSTEXPR_BITCAST 1 - template - [[nodiscard]] constexpr To bit_cast(const From& from) noexcept { - // Available since Clang 9, GCC 11.1, and MSVC 16.6. Otherwise, this function could not be constexpr. - return __builtin_bit_cast(To, from); - } + template + [[nodiscard]] constexpr To bit_cast(const From& from) noexcept { + // Available since Clang 9, GCC 11.1, and MSVC 16.6. Otherwise, this function could not be constexpr. + return __builtin_bit_cast(To, from); + } #else #define FASTGLTF_CONSTEXPR_BITCAST 0 template @@ -419,7 +381,7 @@ namespace fastgltf { return std::byteswap(n); } #else - template, bool> = true> + template, bool> = true> [[nodiscard]] #if FASTGLTF_CONSTEXPR_BITCAST constexpr #endif @@ -431,32 +393,78 @@ namespace fastgltf { } #endif + /** + * Counts the leading zeros from starting the most significant bit. Returns a std::uint8_t as there + * can only ever be 2^6 zeros with 64-bit types. + */ + template +#if FASTGLTF_HAS_CONCEPTS + requires std::integral +#endif + [[nodiscard, gnu::const]] constexpr auto clz(T value) { +#if !FASTGLTF_HAS_CONCEPTS + static_assert(std::is_integral_v); +#endif +#if FASTGLTF_HAS_BIT + return static_cast(std::countl_zero(value)); +#else + // Very naive but working implementation of counting zero bits. Any sane compiler will + // optimise this away, like instead use the bsr x86 instruction. + if (value == 0) return static_cast(sizeof(T) * 8); + std::uint_fast8_t count = 0; + for (auto i = std::numeric_limits::digits - 1; i > 0; --i) { + if ((value >> i) == 1) { + return count; + } + ++count; + } + return count; +#endif + } + + template +#if FASTGLTF_HAS_CONCEPTS + requires std::integral +#endif + [[nodiscard, gnu::const]] constexpr auto popcount(T value) { +#if !FASTGLTF_HAS_CONCEPTS + static_assert(std::is_integral_v); +#endif +#if FASTGLTF_HAS_BIT + return static_cast(std::popcount(value)); +#else + std::uint_fast8_t bits = 0; + while (value) { + if (value & 1) + ++bits; + value >>= 1; + } + return bits; +#endif + } + /** * Returns the absolute value of the given integer in its unsigned type. * This avoids the issue with two complementary signed integers not being able to represent INT_MIN. */ template - constexpr std::make_unsigned_t uabs(T val) { + [[nodiscard]] constexpr std::make_unsigned_t uabs(T val) { if constexpr (std::is_signed_v) { using unsigned_t = std::make_unsigned_t; return (val < 0) - ? static_cast(-(val + 1)) + 1 - : static_cast(val); + ? static_cast(-(val + 1)) + 1 + : static_cast(val); } else { return val; } } - template - struct UniqueDeleter { - template - constexpr void operator()(T* t) const { - callback(t); - } - }; - - template - using deletable_unique_ptr = std::unique_ptr>; + /** + * Simple function to check if the given string starts with a given set of characters. + */ + inline bool startsWith(std::string_view str, std::string_view search) { + return str.rfind(search, 0) == 0; + } } // namespace fastgltf #ifdef _MSC_VER