Add experimental gb.hpp

1 files changed, 2252 insertions, 0 deletions

diff --git a/gb.hpp b/gb.hpp
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+++ b/gb.hpp
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+// gb.hpp - v0.01 - public domain C++11 helper library - no warranty implied; use at your own risk
+// (Experimental) A C++11 helper library without STL geared towards game development
+//
+// Version History:
+//     0.01 - Initial Version
+//
+// LICENSE
+//
+//     This software is in the public domain. Where that dedication is not
+//     recognized, you are granted a perpetual, irrevocable license to copy,
+//     distribute, and modify this file as you see fit.
+//
+// WARNING
+//
+//     This library is highly experimental and features may not work as expected.
+//     This also means that many functions are not documented.
+//
+#ifndef GB_INCLUDE_GB_HPP
+#define GB_INCLUDE_GB_HPP
+
+#if !defined(__cplusplus) && __cplusplus >= 201103L
+#error This library is only for C++11 and above
+#endif
+
+// NOTE(bill): Because static means three different things in C/C++
+//             Great Design(!)
+#define global        static
+#define internal      static
+#define local_persist static
+
+#if defined(_MSC_VER)
+#define _ALLOW_KEYWORD_MACROS
+
+	#if !defined(alignof) // Needed for MSVC 2013
+	#define alignof(x) __alignof(x)
+	#endif
+#endif
+
+////////////////////////////////
+/// System OS                ///
+////////////////////////////////
+#define WIN32_LEAN_AND_MEAN 1
+
+#if defined(_WIN32) || defined(_WIN64)
+#define GB_SYSTEM_WINDOWS
+#define NOMINMAX
+
+#elif defined(__APPLE__) && defined(__MACH__)
+#define GB_SYSTEM_OSX
+
+#elif defined(__unix__)
+#define GB_SYSTEM_UNIX
+
+	#if defined(__linux__)
+	#define GB_SYSTEM_LINUX
+	#elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+	#define GB_SYSTEM_FREEBSD
+	#else
+	#error This UNIX operating system is not supported by gb.hpp
+	#endif
+#else
+#error This operating system is not supported by gb.hpp
+#endif
+
+////////////////////////////////
+/// Environment Bit Size     ///
+////////////////////////////////
+#if defined(_WIN32) || defined(_WIN64)
+	#if defined(_WIN64)
+	#define GB_ARCH_64_BIT
+	#else
+	#define GB_ARCH_32_BIT
+	#endif
+#endif
+
+// TODO(bill): Check if this KEPLER_ENVIRONMENT works on clang
+#if defined(__GNUC__)
+	#if defined(__x86_64__) || defined(__ppc64__)
+	#define GB_ARCH_64_BIT
+	#else
+	#define GB_ARCH_32_BIT
+	#endif
+#endif
+
+#define GB_IS_POWER_OF_TWO(x) ((x) != 0) && !((x) & ((x) - 1))
+
+
+#ifndef NDEBUG
+#define GB_ASSERT(x, ...) ((void)(gb__assert_handler((x), #x, __FILE__, __LINE__, ##__VA_ARGS__)))
+#else
+#define GB_ASSERT(x, ...) ((void)sizeof(x))
+#endif
+
+extern "C" void
+gb__assert_handler(bool condition, const char* condition_str,
+                   const char* filename, size_t line,
+                   const char* error_text = nullptr, ...);
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef GB_SYSTEM_WINDOWS
+#include <windows.h>
+#else
+#include <pthread.h>
+#endif
+
+namespace gb
+{
+////////////////////////////////
+/// Types                    ///
+////////////////////////////////
+
+using u8  = uint8_t;
+using s8  = int8_t;
+using u16 = uint16_t;
+using s16 = int16_t;
+using u32 = uint32_t;
+using s32 = int32_t;
+
+#if defined(_MSC_VER)
+using s64 = signed __int64;
+using u64 = unsigned __int64;
+#else
+using s64 = int64_t;
+using u64 = uint64_t;
+#endif
+
+using f32 = float;
+using f64 = double;
+
+#ifdef GB_B8_AS_BOOL
+using b8 = bool;
+#else
+using b8 = s8;
+#endif
+using b32 = s32;
+
+// NOTE(bill): (std::)size_t is not used not because it's a bad concept but on
+// the platforms that I will be using:
+// sizeof(size_t) == sizeof(usize) == sizeof(ssize)
+// NOTE(bill): This also allows for a signed version of size_t which is similar
+// to ptrdiff_t
+// NOTE(bill): If (u)intptr is a better fit, please use that.
+// NOTE(bill): Also, I hate the `_t` suffix
+#if defined(GB_ARCH_64_BIT)
+using ssize = s64;
+using usize = u64;
+#elif defined(GB_ARCH_32_BIT)
+using ssize = s32;
+using usize = u32;
+#else
+#error Unknown architecture bit size
+#endif
+
+static_assert(sizeof(usize) == sizeof(size_t),
+              "`usize` is not the same size as `size_t`");
+static_assert(sizeof(ssize) == sizeof(usize),
+              "`ssize` is not the same size as `usize`");
+
+using intptr  = intptr_t;
+using uintptr = uintptr_t;
+
+using ptrdiff = ptrdiff_t;
+
+
+////////////////////////////////
+/// C++11 Move Semantics     ///
+////////////////////////////////
+template <typename T> struct Remove_Reference      { using Type = T; };
+template <typename T> struct Remove_Reference<T&>  { using Type = T; };
+template <typename T> struct Remove_Reference<T&&> { using Type = T; };
+
+template <typename T>
+inline T&&
+forward(typename Remove_Reference<T>::Type& t)
+{
+	return static_cast<T &&>(t);
+}
+
+template <typename T>
+inline T&&
+forward(typename Remove_Reference<T>::Type&& t)
+{
+	return static_cast<T &&>(t);
+}
+
+template <typename T>
+inline typename Remove_Reference<T>::Type&&
+move(T&& t)
+{
+	return static_cast<typename Remove_Reference<T>::Type&&>(t);
+}
+
+////////////////////////////////
+/// Defer                    ///
+////////////////////////////////
+namespace impl
+{
+template <typename Fn>
+struct Defer
+{
+	Fn fn;
+
+	Defer(Fn&& fn) : fn{forward<Fn>(fn)} {}
+	~Defer() { fn(); };
+};
+
+template <typename Fn>
+Defer<Fn>
+defer_fn(Fn&& fn) { return Defer<Fn>(forward<Fn>(fn)); }
+} // namespace impl
+} // namespace gb
+
+#define GB_DEFER_1(x, y) x##y
+#define GB_DEFER_2(x, y) GB_DEFER_1(x, y)
+#define GB_DEFER_3(x)    GB_DEFER_2(GB_DEFER_2(x, __COUNTER__), __LINE__)
+#define defer(code) auto GB_DEFER_3(_defer_) = gb::impl::defer_fn([&](){code;})
+
+namespace gb
+{
+////////////////////////////////
+/// Memory                   ///
+////////////////////////////////
+
+struct Mutex
+{
+#ifdef GB_SYSTEM_WINDOWS
+	HANDLE win32_mutex;
+#else
+	pthread_mutex_t posix_mutex;
+#endif
+
+	Mutex();
+	~Mutex();
+};
+
+void lock_mutex(Mutex& mutex);
+bool try_lock_mutex(Mutex& mutex);
+void unlock_mutex(Mutex& mutex);
+
+#define GB_DEFAULT_ALIGNMENT 4
+
+inline void*
+align_forward(void* ptr, usize align)
+{
+	GB_ASSERT(GB_IS_POWER_OF_TWO(align));
+
+	uintptr p = (uintptr)ptr;
+
+	const usize modulo = p % align;
+	if (modulo)
+		p += (uintptr)(align - modulo);
+
+	return (void*)p;
+}
+
+struct Allocator
+{
+	Allocator() {}
+	virtual ~Allocator() {}
+
+	virtual void* alloc(usize size, usize align = GB_DEFAULT_ALIGNMENT) = 0;
+	virtual void  dealloc(void* ptr) = 0;
+	virtual ssize allocated_size(const void* ptr) = 0;
+	virtual ssize total_allocated() = 0;
+
+private:
+	// Delete copying
+	Allocator(const Allocator&) = delete;
+	Allocator& operator=(const Allocator&) = delete;
+};
+
+inline void*
+alloc(Allocator& a, usize size, usize align = GB_DEFAULT_ALIGNMENT)
+{
+	return a.alloc(size, align);
+}
+
+inline void
+dealloc(Allocator& a, void* ptr)
+{
+	return a.dealloc(ptr);
+}
+
+template <typename T>
+inline T*
+alloc_struct(Allocator& a)
+{
+	return static_cast<T*>a.alloc(sizeof(T), alignof(T));
+}
+
+
+template <typename T>
+inline T*
+alloc_array(Allocator& a, usize count)
+{
+	return static_cast<T*>(alloc(a, count * sizeof(T), alignof(T)));
+}
+
+#define GB_HEAP_ALLOCATOR_HEADER_PAD_VALUE (usize)(-1)
+
+struct Heap_Allocator : Allocator
+{
+	struct Header
+	{
+		ssize size;
+	};
+
+	Mutex mutex = Mutex{};
+	ssize total_allocated_count = 0;
+	ssize allocation_count      = 0;
+
+	Heap_Allocator() = default;
+
+	virtual ~Heap_Allocator();
+
+	virtual void* alloc(usize size, usize align = GB_DEFAULT_ALIGNMENT);
+	virtual void  dealloc(void* ptr);
+	virtual ssize allocated_size(const void* ptr);
+	virtual ssize total_allocated();
+};
+
+
+struct Arena_Allocator : Allocator
+{
+	ssize base_size;
+	u8*   base;
+	ssize total_allocated_count;
+	ssize temp_count;
+
+	virtual void* alloc(usize size, usize align = GB_DEFAULT_ALIGNMENT);
+	virtual void  dealloc(void* ptr);
+	virtual ssize allocated_size(const void* ptr);
+	virtual ssize total_allocated();
+
+	virtual usize get_alignment_offset(usize align = GB_DEFAULT_ALIGNMENT);
+	virtual usize get_remaining_space(usize align = GB_DEFAULT_ALIGNMENT);
+	void check();
+};
+
+inline void
+init_arena_allocator(Arena_Allocator& arena, void* base, usize base_size)
+{
+	arena.base_size  = base_size;
+	arena.base       = (u8*)base;
+	arena.temp_count = 0;
+	arena.total_allocated_count = 0;
+}
+
+struct Temporary_Arena_Memory
+{
+	Arena_Allocator* arena;
+	ssize original_count;
+
+	explicit Temporary_Arena_Memory(Arena_Allocator& arena_)
+	: arena(&arena_)
+	, original_count(arena_.total_allocated_count)
+	{
+	}
+
+	~Temporary_Arena_Memory()
+	{
+		GB_ASSERT(arena->total_allocated() >= original_count);
+		arena->total_allocated_count = original_count;
+		GB_ASSERT(arena->temp_count > 0);
+		arena->temp_count--;
+	}
+};
+
+inline Temporary_Arena_Memory
+make_temporary_arena_memory(Arena_Allocator& arena)
+{
+	return Temporary_Arena_Memory{arena};
+}
+
+////////////////////////////////
+/// Array                    ///
+////////////////////////////////
+
+template <typename T>
+struct Array
+{
+	Allocator* allocator;
+	ssize count;
+	ssize allocation;
+	T*    data;
+
+	virtual ~Array() { if (allocator) dealloc(*allocator, data); }
+
+	const T& operator[](usize index) const { return data[index]; }
+	      T& operator[](usize index)       { return data[index]; }
+};
+
+template <typename T> Array<T> make_array(Allocator& allocator, usize count = 0);
+template <typename T> void     free_array(Array<T>& array);
+
+template <typename T> void append_array(Array<T>& a, const T& item);
+template <typename T> void append_array(Array<T>& a, const T* items, usize count);
+
+template <typename T> void pop_back_array(Array<T>& a);
+
+template <typename T> inline       T* begin(Array<T>& a)       { return a.data; }
+template <typename T> inline const T* begin(const Array<T>& a) { return a.data; }
+
+template <typename T> inline       T* end(Array<T>& a)         { return a.data + a.count; }
+template <typename T> inline const T* end(const Array<T>& a)   { return a.data + a.count; }
+
+template <typename T> void clear_array(Array<T>& a);
+template <typename T> void resize_array(Array<T>& a, usize count);
+template <typename T> void reserve_array(Array<T>& a, usize allocation);
+template <typename T> void set_array_allocation(Array<T>& a, usize allocation);
+template <typename T> void grow_array(Array<T>& a, usize min_allocation = 0);
+
+
+template <typename T>
+inline Array<T>
+make_array(Allocator& allocator, usize count)
+{
+	Array<T> array = {};
+	array.allocator = &allocator;
+	if (count > 0)
+	{
+		array.data = alloc_array<T>(allocator, count);
+		if (array.data)
+		{
+			array.count = array.allocation = count;
+		}
+	}
+
+	return array;
+}
+
+template <typename T>
+inline void
+dealloc_array(Array<T>& array)
+{
+	if (array.allocator)
+		dealloc(*array.allocator, array.data);
+}
+
+template <typename T>
+inline void
+append_array(Array<T>& a, const T& item)
+{
+	if (a.allocation < a.count + 1)
+		grow_array(a);
+	a.data[a.count++] = item;
+}
+
+template <typename T>
+inline void
+append_array(Array<T>& a, const T* items, usize count)
+{
+	if (a.allocation <= a.count + count)
+		grow_array(a, a.count + count);
+
+	memcpy(&a.data[a.count], items, count * sizeof(T));
+	a.count += count;
+}
+
+template <typename T>
+inline void
+pop_back_array(Array<T>& a)
+{
+	GB_ASSERT(a.count > 0);
+
+	a.count--;
+}
+
+template <typename T>
+inline void
+clear_array(Array<T>& a)
+{
+	resize_array(a, 0);
+}
+
+template <typename T>
+inline void
+resize_array(Array<T>& a, usize count)
+{
+	if (a.allocation < (ssize)count)
+		grow_array(a, count);
+	a.count = count;
+}
+
+template <typename T>
+inline void
+reserve_array(Array<T>& a, usize allocation)
+{
+	if (a.allocation < (ssize)allocation)
+		set_array_allocation(a, allocation);
+}
+
+template <typename T>
+inline void
+set_array_allocation(Array<T>& a, usize allocation)
+{
+	if ((ssize)allocation == a.allocation)
+		return;
+
+	if ((ssize)allocation < a.count)
+		resize_array(a, allocation);
+
+	T* data = nullptr;
+	if (allocation > 0)
+	{
+		data = alloc_array<T>(*a.allocator, allocation);
+		memcpy(data, a.data, a.count * sizeof(T));
+	}
+	dealloc(*a.allocator, a.data);
+	a.data = data;
+	a.allocation = allocation;
+}
+
+template <typename T>
+inline void
+grow_array(Array<T>& a, usize min_allocation)
+{
+	usize allocation = 2 * a.allocation + 2;
+	if (allocation < min_allocation)
+		allocation = min_allocation;
+	set_array_allocation(a, allocation);
+}
+
+
+
+
+////////////////////////////////
+/// Math Types               ///
+////////////////////////////////
+
+struct Vector2
+{
+	union
+	{
+		struct { f32 x, y; };
+		f32 data[2];
+	};
+
+	inline const f32& operator[](usize index) const { return data[index]; }
+	inline       f32& operator[](usize index)       { return data[index]; }
+};
+
+struct Vector3
+{
+	union
+	{
+		struct { f32 x, y, z; };
+		Vector2 xy;
+		f32 data[3];
+	};
+
+	inline const f32& operator[](usize index) const { return data[index]; }
+	inline       f32& operator[](usize index)       { return data[index]; }
+};
+
+struct Vector4
+{
+	union
+	{
+		struct { f32 x, y, z, w; };
+		struct { Vector2 xy, zw; };
+		Vector3 xyz;
+		f32 data[4];
+	};
+
+	inline const f32& operator[](usize index) const { return data[index]; }
+	inline       f32& operator[](usize index)       { return data[index]; }
+};
+
+struct Quaternion
+{
+	union
+	{
+		struct { f32 x, y, z, w; };
+		Vector3 xyz;
+		f32 data[4];
+	};
+};
+
+
+struct Matrix4
+{
+	union
+	{
+		struct { Vector4 x, y, z, w; };
+		Vector4 column[4];
+		f32     data[16];
+	};
+
+	inline const Vector4& operator[](usize index) const { return column[index]; }
+	inline       Vector4& operator[](usize index)       { return column[index]; }
+};
+
+
+struct Euler_Angles
+{
+	// NOTE(bill): All angles in radians
+	f32 pitch;
+	f32 yaw;
+	f32 roll;
+};
+
+extern const Vector2    VECTOR2_ZERO;
+extern const Vector3    VECTOR3_ZERO;
+extern const Vector4    VECTOR4_ZERO;
+extern const Quaternion QUATERNION_IDENTITY;
+extern const Matrix4    MATRIX4_IDENTITY;
+
+////////////////////////////////
+/// Math Type Op Overloads   ///
+////////////////////////////////
+
+// Vector2 Operators
+bool operator==(const Vector2& a, const Vector2& b);
+bool operator!=(const Vector2& a, const Vector2& b);
+
+Vector2 operator-(const Vector2& a);
+
+Vector2 operator+(const Vector2& a, const Vector2& b);
+Vector2 operator-(const Vector2& a, const Vector2& b);
+
+Vector2 operator*(const Vector2& a, f32 scalar);
+Vector2 operator*(f32 scalar, const Vector2& a);
+
+Vector2 operator/(const Vector2& a, f32 scalar);
+
+Vector2 operator*(const Vector2& a, const Vector2& b); // Hadamard Product
+Vector2 operator/(const Vector2& a, const Vector2& b); // Hadamard Product
+
+Vector2& operator+=(Vector2& a, const Vector2& b);
+Vector2& operator-=(Vector2& a, const Vector2& b);
+Vector2& operator*=(Vector2& a, f32 scalar);
+Vector2& operator/=(Vector2& a, f32 scalar);
+
+// Vector3 Operators
+bool operator==(const Vector3& a, const Vector3& b);
+bool operator!=(const Vector3& a, const Vector3& b);
+
+Vector3 operator-(const Vector3& a);
+
+Vector3 operator+(const Vector3& a, const Vector3& b);
+Vector3 operator-(const Vector3& a, const Vector3& b);
+
+Vector3 operator*(const Vector3& a, f32 scalar);
+Vector3 operator*(f32 scalar, const Vector3& a);
+
+Vector3 operator/(const Vector3& a, f32 scalar);
+
+Vector3 operator*(const Vector3& a, const Vector3& b); // Hadamard Product
+Vector3 operator/(const Vector3& a, const Vector3& b); // Hadamard Product
+
+Vector3& operator+=(Vector3& a, const Vector3& b);
+Vector3& operator-=(Vector3& a, const Vector3& b);
+Vector3& operator*=(Vector3& a, f32 scalar);
+Vector3& operator/=(Vector3& a, f32 scalar);
+
+// Vector4 Operators
+bool operator==(const Vector4& a, const Vector4& b);
+bool operator!=(const Vector4& a, const Vector4& b);
+
+Vector4 operator-(const Vector4& a);
+
+Vector4 operator+(const Vector4& a, const Vector4& b);
+Vector4 operator-(const Vector4& a, const Vector4& b);
+
+Vector4 operator*(const Vector4& a, f32 scalar);
+Vector4 operator*(f32 scalar, const Vector4& a);
+
+Vector4 operator/(const Vector4& a, f32 scalar);
+
+Vector4 operator*(const Vector4& a, const Vector4& b); // Hadamard Product
+Vector4 operator/(const Vector4& a, const Vector4& b); // Hadamard Product
+
+Vector4& operator+=(Vector4& a, const Vector4& b);
+Vector4& operator-=(Vector4& a, const Vector4& b);
+Vector4& operator*=(Vector4& a, f32 scalar);
+Vector4& operator/=(Vector4& a, f32 scalar);
+
+// Quaternion Operators
+bool operator==(const Quaternion& a, const Quaternion& b);
+bool operator!=(const Quaternion& a, const Quaternion& b);
+
+Quaternion operator-(const Quaternion& a);
+
+Quaternion operator+(const Quaternion& a, const Quaternion& b);
+Quaternion operator-(const Quaternion& a, const Quaternion& b);
+
+Quaternion operator*(const Quaternion& a, const Quaternion& b);
+Quaternion operator*(const Quaternion& a, f32 s);
+Quaternion operator*(f32 s, const Quaternion& a);
+
+Quaternion operator/(const Quaternion& a, f32 s);
+
+// Matrix4 Operators
+bool operator==(const Matrix4& a, const Matrix4& b);
+bool operator!=(const Matrix4& a, const Matrix4& b);
+
+Matrix4 operator+(const Matrix4& a, const Matrix4& b);
+Matrix4 operator-(const Matrix4& a, const Matrix4& b);
+
+Matrix4 operator*(const Matrix4& a, const Matrix4& b);
+Vector4 operator*(const Matrix4& a, const Vector4& v);
+Matrix4 operator*(const Matrix4& a, f32 scalar);
+Matrix4 operator*(f32 scalar, const Matrix4& a);
+
+Matrix4 operator/(const Matrix4& a, f32 scalar);
+
+Matrix4& operator+=(Matrix4& a, const Matrix4& b);
+Matrix4& operator-=(Matrix4& a, const Matrix4& b);
+Matrix4& operator*=(Matrix4& a, const Matrix4& b);
+
+//////////////////////////////////
+/// Math Functions & Constants ///
+//////////////////////////////////
+
+namespace math
+{
+extern const f32 EPSILON;
+extern const f32 ZERO;
+extern const f32 ONE;
+extern const f32 THIRD;
+extern const f32 TWO_THIRDS;
+extern const f32 E;
+extern const f32 PI;
+extern const f32 TAU;
+extern const f32 SQRT_2;
+extern const f32 SQRT_3;
+
+
+// Power
+f32 sqrt(f32 x);
+f32 pow(f32 x, f32 y);
+f32 cbrt(f32 x);
+f32 fast_inv_sqrt(f32 x);
+
+// Trigonometric
+f32 sin(f32 radians);
+f32 cos(f32 radians);
+f32 tan(f32 radians);
+
+f32 asin(f32 x);
+f32 acos(f32 x);
+f32 atan(f32 x);
+f32 atan2(f32 y, f32 x);
+
+f32 radians(f32 degrees);
+f32 degrees(f32 radians);
+
+// Hyperbolic
+f32 sinh(f32 x);
+f32 cosh(f32 x);
+f32 tanh(f32 x);
+
+f32 asinh(f32 x);
+f32 acosh(f32 x);
+f32 atanh(f32 x);
+
+// Rounding
+f32 ceil(f32 x);
+f32 floor(f32 x);
+f32 mod(f32 x, f32 y);
+f32 truncate(f32 x);
+f32 round(f32 x);
+
+s32 sign(s32 x);
+s64 sign(s64 x);
+f32 sign(f32 x);
+
+// Other
+f32 abs(f32 x);
+s8  abs( s8 x);
+s16 abs(s16 x);
+s32 abs(s32 x);
+s64 abs(s64 x);
+
+
+// Vector2 functions
+f32 dot(const Vector2& a, const Vector2& b);
+f32 cross(const Vector2& a, const Vector2& b);
+
+f32 magnitude(const Vector2& a);
+Vector2 normalize(const Vector2& a);
+
+Vector2 hadamard_product(const Vector2& a, const Vector2& b);
+
+// Vector3 functions
+f32 dot(const Vector3& a, const Vector3& b);
+Vector3 cross(const Vector3& a, const Vector3& b);
+
+f32 magnitude(const Vector3& a);
+Vector3 normalize(const Vector3& a);
+
+Vector3 hadamard_product(const Vector3& a, const Vector3& b);
+
+// Vector4 functions
+f32 dot(const Vector4& a, const Vector4& b);
+
+f32 magnitude(const Vector4& a);
+Vector4 normalize(const Vector4& a);
+
+Vector4 hadamard_product(const Vector4& a, const Vector4& b);
+
+// Quaternion functions
+f32 dot(const Quaternion& a, const Quaternion& b);
+Quaternion cross(const Quaternion& a, const Quaternion& b);
+
+f32 magnitude(const Quaternion& a);
+Quaternion normalize(const Quaternion& a);
+
+Quaternion conjugate(const Quaternion& a);
+Quaternion inverse(const Quaternion& a);
+
+Vector3 operator*(const Quaternion& a, const Vector3& v); // Rotate v by a
+
+f32 quaternion_angle(const Quaternion& a);
+Vector3 quaternion_axis(const Quaternion& a);
+Quaternion axis_angle(const Vector3& axis, f32 radians);
+
+f32 quaternion_roll(const Quaternion& a);
+f32 quaternion_pitch(const Quaternion& a);
+f32 quaternion_yaw(const Quaternion& a);
+
+Euler_Angles quaternion_to_euler_angles(const Quaternion& a);
+Quaternion euler_angles_to_quaternion(const Euler_Angles& e,
+                                      const Vector3& x_axis = {1, 0, 0},
+                                      const Vector3& y_axis = {0, 1, 0},
+                                      const Vector3& z_axis = {0, 0, 1});
+
+// Matrix4 functions
+Matrix4 transpose(const Matrix4& m);
+f32 determinant(const Matrix4& m);
+
+Matrix4 inverse(const Matrix4& m);
+
+Matrix4 hadamard_product(const Matrix4& a, const Matrix4&b);
+
+Matrix4 quaternion_to_matrix4(const Quaternion& a);
+Quaternion matrix4_to_quaternion(const Matrix4& m);
+
+Matrix4 translate(const Vector3& v);
+Matrix4 rotate(const Vector3& v, f32 radians);
+Matrix4 scale(const Vector3& v);
+Matrix4 ortho(f32 left, f32 right, f32 bottom, f32 top);
+Matrix4 ortho(f32 left, f32 right, f32 bottom, f32 top, f32 z_near, f32 z_far);
+Matrix4 perspective(f32 fovy_radians, f32 aspect, f32 z_near, f32 z_far);
+Matrix4 infinite_perspective(f32 fovy_radians, f32 aspect, f32 z_near);
+
+Matrix4
+look_at_matrix4(const Vector3& eye, const Vector3& center, const Vector3& up = {0, 1, 0});
+
+Quaternion
+look_at_quaternion(const Vector3& eye, const Vector3& center, const Vector3& up = {0, 1, 0});
+
+
+} // namespace math
+} // namespace gb
+#endif // GB_INCLUDE_GB_HPP
+
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+///
+/// It's a long way to Tipperary
+///
+///
+///
+///
+///
+////////////////////////////////
+/// Implemenation            ///
+////////////////////////////////
+#ifdef GB_IMPLEMENTATION
+
+#include <float.h>
+#include <math.h>
+#include <stdarg.h>
+
+inline void
+gb__assert_handler(bool condition, const char* condition_str,
+                    const char* filename, size_t line,
+                    const char* error_text, ...)
+{
+	if (condition)
+		return;
+
+	fprintf(stderr, "ASSERT! %s(%d): %s", filename, line, condition_str);
+	if (error_text)
+	{
+		fprintf(stderr, " - ");
+
+		va_list args;
+		va_start(args, error_text);
+		vfprintf(stderr, error_text, args);
+		va_end(args);
+	}
+	fprintf(stderr, "\n");
+
+	*(int*)0 = 0; // TODO(bill): Use a better way to assert
+}
+
+
+
+namespace gb
+{
+////////////////////////////////
+/// Memory                   ///
+////////////////////////////////
+
+Mutex::Mutex()
+{
+#ifdef GB_SYSTEM_WINDOWS
+	win32_mutex = CreateMutex(0, 0, 0);
+#else
+	pthread_mutex_init(&posix_mutex, nullptr);
+#endif
+}
+
+Mutex::~Mutex()
+{
+#ifdef GB_SYSTEM_WINDOWS
+	CloseHandle(win32_mutex);
+#else
+	pthread_mutex_destroy(&posix_mutex);
+#endif
+}
+
+void lock_mutex(Mutex& mutex)
+{
+#ifdef GB_SYSTEM_WINDOWS
+	WaitForSingleObject(mutex.win32_mutex, INFINITE);
+#else
+	pthread_mutex_lock(&mutex.posix_mutex);
+#endif
+}
+
+bool try_lock_mutex(Mutex& mutex)
+{
+#ifdef GB_SYSTEM_WINDOWS
+	return WaitForSingleObject(mutex.win32_mutex, 0) == WAIT_OBJECT_0;
+#else
+	return pthread_mutex_trylock(&mutex.posix_mutex) == 0;
+#endif
+}
+
+
+void unlock_mutex(Mutex& mutex)
+{
+#ifdef GB_SYSTEM_WINDOWS
+	ReleaseMutex(mutex.win32_mutex);
+#else
+	pthread_mutex_unlock(&mutex.posix_mutex);
+#endif
+}
+
+
+Heap_Allocator::~Heap_Allocator()
+{
+	GB_ASSERT(allocation_count == 0 && total_allocated() == 0,
+	          "Heap Allocator: allocation count = %lld; total allocated = %lld",
+	          allocation_count, total_allocated());
+}
+
+void*
+Heap_Allocator::alloc(usize size, usize align)
+{
+	lock_mutex(mutex);
+	defer(unlock_mutex(mutex));
+
+	const usize total = size + align + sizeof(Header);
+	Header* h = (Header*)malloc(total);
+	h->size   = total;
+
+	void* data = align_forward(h + 1, align);
+	{ // Pad header
+		usize* ptr = (usize*)(h+1);
+
+		while (ptr != data)
+			*ptr++ = GB_HEAP_ALLOCATOR_HEADER_PAD_VALUE;
+	}
+	total_allocated_count += total;
+	allocation_count++;
+
+	return data;
+}
+
+void
+Heap_Allocator::dealloc(void* ptr)
+{
+	if (!ptr)
+		return;
+
+	lock_mutex(mutex);
+	defer(unlock_mutex(mutex));
+
+	const usize* data = ((usize*)ptr) - 1;
+
+	while (*data == GB_HEAP_ALLOCATOR_HEADER_PAD_VALUE)
+		data--;
+
+	Header* h = (Header*)data;
+
+	total_allocated_count -= h->size;
+	allocation_count--;
+
+	free(h);
+}
+
+ssize
+Heap_Allocator::allocated_size(const void* ptr)
+{
+	lock_mutex(mutex);
+	defer(unlock_mutex(mutex));
+
+	const usize* data = (usize*)ptr - 1;
+
+	while (*data == GB_HEAP_ALLOCATOR_HEADER_PAD_VALUE)
+		data--;
+
+	return ((Header*)ptr)->size;
+}
+
+ssize
+Heap_Allocator::total_allocated()
+{
+	return total_allocated_count;
+}
+
+
+void* Arena_Allocator::alloc(usize size_init, usize align)
+{
+	usize size = size_init;
+
+	usize alignment_offset = get_alignment_offset(align);
+	size += alignment_offset;
+
+	GB_ASSERT(size >= size_init);
+	GB_ASSERT(total_allocated_count + size <= (usize)base_size);
+
+	void* ptr = base + total_allocated_count + alignment_offset;
+	total_allocated_count += size;
+
+	return ptr;
+}
+
+ssize Arena_Allocator::allocated_size(const void* ptr)
+{
+	return -1;
+}
+
+ssize Arena_Allocator::total_allocated()
+{
+	return total_allocated_count;
+}
+
+usize Arena_Allocator::get_alignment_offset(usize align)
+{
+	usize offset = 0;
+
+	usize result_pointer = (usize)((uintptr)base + total_allocated_count);
+	usize alignment_mask = align - 1;
+	if (result_pointer & alignment_mask)
+		offset = align - (result_pointer & alignment_mask);
+
+	return offset;
+}
+
+usize Arena_Allocator::get_remaining_space(usize align)
+{
+	return base_size - (total_allocated_count + get_alignment_offset(align));
+}
+
+void Arena_Allocator::check()
+{
+	GB_ASSERT(temp_count == 0);
+}
+
+
+
+
+////////////////////////////////
+/// Math                     ///
+////////////////////////////////
+
+
+const Vector2    VECTOR2_ZERO        = {0, 0};
+const Vector3    VECTOR3_ZERO        = {0, 0, 0};
+const Vector4    VECTOR4_ZERO        = {0, 0, 0, 0};
+const Quaternion QUATERNION_IDENTITY = {0, 0, 0, 1};
+const Matrix4    MATRIX4_IDENTITY    = {1, 0, 0, 0,
+                                        0, 1, 0, 0,
+                                        0, 0, 1, 0,
+                                        0, 0, 0, 1};
+
+
+////////////////////////////////
+/// Math Type Op Overloads   ///
+////////////////////////////////
+
+// Vector2 Operators
+bool operator==(const Vector2& a, const Vector2& b)
+{
+	return (a.x == b.x) && (a.y == b.y);
+}
+
+bool operator!=(const Vector2& a, const Vector2& b)
+{
+	return !operator==(a, b);
+}
+
+Vector2 operator-(const Vector2& a)
+{
+	return {-a.x, -a.y};
+}
+
+Vector2 operator+(const Vector2& a, const Vector2& b)
+{
+	return {a.x + b.x, a.y + b.y};
+}
+
+Vector2 operator-(const Vector2& a, const Vector2& b)
+{
+	return {a.x - b.x, a.y - b.y};
+}
+
+Vector2 operator*(const Vector2& a, f32 scalar)
+{
+	return {a.x * scalar, a.y * scalar};
+}
+
+Vector2 operator*(f32 scalar, const Vector2& a)
+{
+	return {a.x * scalar, a.y * scalar};
+}
+
+Vector2 operator/(const Vector2& a, f32 scalar)
+{
+	return {a.x / scalar, a.y / scalar};
+}
+
+Vector2 operator*(const Vector2& a, const Vector2& b) // Hadamard Product
+{
+	return {a.x * b.x, a.y * b.y};
+}
+
+Vector2 operator/(const Vector2& a, const Vector2& b) // Hadamard Product
+{
+	return {a.x / b.x, a.y / b.y};
+}
+
+Vector2& operator+=(Vector2& a, const Vector2& b)
+{
+	a.x += b.x;
+	a.y += b.y;
+
+	return a;
+}
+
+Vector2& operator-=(Vector2& a, const Vector2& b)
+{
+	a.x -= b.x;
+	a.y -= b.y;
+
+	return a;
+}
+
+Vector2& operator*=(Vector2& a, f32 scalar)
+{
+	a.x *= scalar;
+	a.y *= scalar;
+
+	return a;
+}
+
+Vector2& operator/=(Vector2& a, f32 scalar)
+{
+	a.x /= scalar;
+	a.y /= scalar;
+
+	return a;
+}
+
+// Vector3 Operators
+bool operator==(const Vector3& a, const Vector3& b)
+{
+	return (a.x == b.x) && (a.y == b.y) && (a.z == b.z);
+}
+
+bool operator!=(const Vector3& a, const Vector3& b)
+{
+	return !operator==(a, b);
+}
+
+Vector3 operator-(const Vector3& a)
+{
+	return {-a.x, -a.y, -a.z};
+}
+
+Vector3 operator+(const Vector3& a, const Vector3& b)
+{
+	return {a.x + b.x, a.y + b.y, a.z + b.z};
+}
+
+Vector3 operator-(const Vector3& a, const Vector3& b)
+{
+	return {a.x - b.x, a.y - b.y, a.z - b.z};
+}
+
+Vector3 operator*(const Vector3& a, f32 scalar)
+{
+	return {a.x * scalar, a.y * scalar, a.z * scalar};
+}
+
+Vector3 operator*(f32 scalar, const Vector3& a)
+{
+	return {a.x * scalar, a.y * scalar, a.z * scalar};
+}
+
+Vector3 operator/(const Vector3& a, f32 scalar)
+{
+	return {a.x / scalar, a.y / scalar, a.z / scalar};
+}
+
+Vector3 operator*(const Vector3& a, const Vector3& b) // Hadamard Product
+{
+	return {a.x * b.x, a.y * b.y, a.z * b.z};
+}
+
+Vector3 operator/(const Vector3& a, const Vector3& b) // Hadamard Product
+{
+	return {a.x / b.x, a.y / b.y, a.z / b.z};
+}
+
+Vector3& operator+=(Vector3& a, const Vector3& b)
+{
+	a.x += b.x;
+	a.y += b.y;
+	a.z += b.z;
+
+	return a;
+}
+
+Vector3& operator-=(Vector3& a, const Vector3& b)
+{
+	a.x -= b.x;
+	a.y -= b.y;
+	a.z -= b.z;
+
+	return a;
+}
+
+Vector3& operator*=(Vector3& a, f32 scalar)
+{
+	a.x *= scalar;
+	a.y *= scalar;
+	a.z *= scalar;
+
+	return a;
+}
+
+Vector3& operator/=(Vector3& a, f32 scalar)
+{
+	a.x /= scalar;
+	a.y /= scalar;
+	a.z /= scalar;
+
+	return a;
+}
+
+// Vector4 Operators
+bool operator==(const Vector4& a, const Vector4& b)
+{
+	return (a.x == b.x) && (a.y == b.y) && (a.z == b.z) && (a.w == b.w);
+}
+
+bool operator!=(const Vector4& a, const Vector4& b)
+{
+	return !operator==(a, b);
+}
+
+Vector4 operator-(const Vector4& a)
+{
+	return {-a.x, -a.y, -a.z, -a.w};
+}
+
+Vector4 operator+(const Vector4& a, const Vector4& b)
+{
+	return {a.x + b.x, a.y + b.y, a.z + b.z, a.w + b.w};
+}
+
+Vector4 operator-(const Vector4& a, const Vector4& b)
+{
+	return {a.x - b.x, a.y - b.y, a.z - b.z, a.w - b.w};
+}
+
+Vector4 operator*(const Vector4& a, f32 scalar)
+{
+	return {a.x * scalar, a.y * scalar, a.z * scalar, a.w * scalar};
+}
+
+Vector4 operator*(f32 scalar, const Vector4& a)
+{
+	return {a.x * scalar, a.y * scalar, a.z * scalar, a.w * scalar};
+}
+
+Vector4 operator/(const Vector4& a, f32 scalar)
+{
+	return {a.x / scalar, a.y / scalar, a.z / scalar, a.w / scalar};
+}
+
+Vector4 operator*(const Vector4& a, const Vector4& b) // Hadamard Product
+{
+	return {a.x * b.x, a.y * b.y, a.z * b.z, a.w * b.w};
+}
+
+Vector4 operator/(const Vector4& a, const Vector4& b) // Hadamard Product
+{
+	return {a.x / b.x, a.y / b.y, a.z / b.z, a.w / b.w};
+}
+
+Vector4& operator+=(Vector4& a, const Vector4& b)
+{
+	a.x += b.x;
+	a.y += b.y;
+	a.z += b.z;
+	a.w += b.w;
+
+	return a;
+}
+
+Vector4& operator-=(Vector4& a, const Vector4& b)
+{
+	a.x -= b.x;
+	a.y -= b.y;
+	a.z -= b.z;
+	a.w -= b.w;
+
+	return a;
+}
+
+Vector4& operator*=(Vector4& a, f32 scalar)
+{
+	a.x *= scalar;
+	a.y *= scalar;
+	a.z *= scalar;
+	a.w *= scalar;
+
+	return a;
+}
+
+Vector4& operator/=(Vector4& a, f32 scalar)
+{
+	a.x /= scalar;
+	a.y /= scalar;
+	a.z /= scalar;
+	a.w /= scalar;
+
+	return a;
+}
+
+// Quaternion Operators
+bool operator==(const Quaternion& a, const Quaternion& b)
+{
+	return (a.x == b.x) && (a.y == b.y) && (a.z == b.z) && (a.w == b.w);
+}
+
+bool operator!=(const Quaternion& a, const Quaternion& b)
+{
+	return !operator==(a, b);
+}
+
+Quaternion operator-(const Quaternion& a)
+{
+	return {-a.x, -a.y, -a.z, -a.w};
+	return {-a.x, -a.y, -a.z, -a.w};
+}
+
+Quaternion operator+(const Quaternion& a, const Quaternion& b)
+{
+	return {a.x + b.x, a.y + b.y, a.z + b.z, a.w + b.w};
+}
+
+Quaternion operator-(const Quaternion& a, const Quaternion& b)
+{
+	return {a.x - b.x, a.y - b.y, a.z - b.z, a.w - b.w};
+
+}
+
+Quaternion operator*(const Quaternion& a, const Quaternion& b)
+{
+	Quaternion q = {};
+
+	q.x = a.w * b.x + a.x * b.w + a.y * b.z - a.z * b.y;
+	q.y = a.w * b.y - a.x * b.z + a.y * b.w + a.z * b.x;
+	q.z = a.w * b.z + a.x * b.y - a.y * b.x + a.z * b.w;
+	q.w = a.w * b.w - a.x * b.x - a.y * b.y - a.z * b.z;
+
+	return q;
+}
+
+Quaternion operator*(const Quaternion& a, f32 s)
+{
+	return {a.x * s, a.y * s, a.z * s, a.w * s};
+}
+
+Quaternion operator*(f32 s, const Quaternion& a)
+{
+	return {a.x * s, a.y * s, a.z * s, a.w * s};
+}
+
+Quaternion operator/(const Quaternion& a, f32 s)
+{
+	return {a.x / s, a.y / s, a.z / s, a.w / s};
+}
+
+// Matrix4 Operators
+bool operator==(const Matrix4& a, const Matrix4& b)
+{
+	for (usize i = 0; i < 4; i++)
+	{
+		if (a[i] != b[i])
+			return false;
+	}
+	return true;
+}
+
+bool operator!=(const Matrix4& a, const Matrix4& b)
+{
+	return !operator==(a, b);
+}
+
+Matrix4 operator+(const Matrix4& a, const Matrix4& b)
+{
+	Matrix4 mat;
+	for (usize i = 0; i < 4; i++)
+		mat[i] = a[i] + b[i];
+	return mat;
+}
+
+Matrix4 operator-(const Matrix4& a, const Matrix4& b)
+{
+	Matrix4 mat;
+	for (usize i = 0; i < 4; i++)
+		mat[i] = a[i] - b[i];
+	return mat;
+}
+
+Matrix4 operator*(const Matrix4& a, const Matrix4& b)
+{
+	Matrix4 result;
+	result[0] = a[0] * b[0][0] + a[1] * b[0][1] + a[2] * b[0][2] + a[3] * b[0][3];
+	result[1] = a[0] * b[1][0] + a[1] * b[1][1] + a[2] * b[1][2] + a[3] * b[1][3];
+	result[2] = a[0] * b[2][0] + a[1] * b[2][1] + a[2] * b[2][2] + a[3] * b[2][3];
+	result[3] = a[0] * b[3][0] + a[1] * b[3][1] + a[2] * b[3][2] + a[3] * b[3][3];
+	return result;
+}
+
+Vector4 operator*(const Matrix4& a, const Vector4& v)
+{
+	Vector4 mul0 = a[0] * v[0];
+	Vector4 mul1 = a[1] * v[1];
+	Vector4 mul2 = a[2] * v[2];
+	Vector4 mul3 = a[3] * v[3];
+
+	Vector4 add0 = mul0 + mul1;
+	Vector4 add1 = mul2 + mul3;
+
+	return add0 + add1;
+}
+
+Matrix4 operator*(const Matrix4& a, f32 scalar)
+{
+	Matrix4 mat;
+	for (usize i = 0; i < 4; i++)
+		mat[i] = a[i] * scalar;
+	return mat;
+}
+
+Matrix4 operator*(f32 scalar, const Matrix4& a)
+{
+	Matrix4 mat;
+	for (usize i = 0; i < 4; i++)
+		mat[i] = a[i] * scalar;
+	return mat;
+}
+
+Matrix4 operator/(const Matrix4& a, f32 scalar)
+{
+	Matrix4 mat;
+	for (usize i = 0; i < 4; i++)
+		mat[i] = a[i] / scalar;
+	return mat;
+}
+
+Matrix4& operator+=(Matrix4& a, const Matrix4& b)
+{
+	return (a = a + b);
+}
+
+Matrix4& operator-=(Matrix4& a, const Matrix4& b)
+{
+	return (a = a - b);
+}
+
+Matrix4& operator*=(Matrix4& a, const Matrix4& b)
+{
+	return (a = a * b);
+}
+
+////////////////////////////////
+/// Math Functions           ///
+////////////////////////////////
+
+
+namespace math
+{
+const f32 EPSILON    = FLT_EPSILON;
+const f32 ZERO       = 0.0f;
+const f32 ONE        = 1.0f;
+const f32 THIRD      = 0.33333333f;
+const f32 TWO_THIRDS = 0.66666667f;
+const f32 E          = 2.718281828f;
+const f32 PI         = 3.141592654f;
+const f32 TAU        = 6.283185307f;
+const f32 SQRT_2     = 1.414213562f;
+const f32 SQRT_3     = 1.732050808f;
+
+// Power
+inline f32 sqrt(f32 x) { return ::sqrtf(x); }
+inline f32 pow(f32 x, f32 y) { return (f32)::powf(x, y); }
+inline f32 cbrt(f32 x) { return (f32)::cbrtf(x); }
+
+inline f32 fast_inv_sqrt(f32 x)
+{
+	const f32 three_halfs = 1.5f;
+
+	f32 x2 = x * 0.5f;
+	f32 y  = x;
+	u32 i  = *(u32*)&y;                       // Evil floating point bit level hacking
+	//	i = 0x5f3759df - (i >> 1);            // What the fuck? Old
+	i = 0x5f375a86 - (i >> 1);                // What the fuck? Improved!
+	y = *(f32*)&i;
+	y = y * (three_halfs - (x2 * y * y));     // 1st iteration
+	//	y = y * (three_halfs - (x2 * y * y)); // 2nd iteration, this can be removed
+
+	return y;
+}
+
+// Trigonometric
+inline f32 sin(f32 radians) { return ::sinf(radians); }
+inline f32 cos(f32 radians) { return ::cosf(radians); }
+inline f32 tan(f32 radians) { return ::tanf(radians); }
+
+inline f32 asin(f32 x)         { return ::asinf(x); }
+inline f32 acos(f32 x)         { return ::acosf(x); }
+inline f32 atan(f32 x)         { return ::atanf(x); }
+inline f32 atan2(f32 y, f32 x) { return ::atan2f(y, x); }
+
+inline f32 radians(f32 degrees) { return TAU * degrees / 360.0f; }
+inline f32 degrees(f32 radians) { return 360.0f * radians / TAU; }
+
+// Hyperbolic
+inline f32 sinh(f32 x) { return ::sinhf(x); }
+inline f32 cosh(f32 x) { return ::coshf(x); }
+inline f32 tanh(f32 x) { return ::tanhf(x); }
+
+inline f32 asinh(f32 x) { return ::asinhf(x); }
+inline f32 acosh(f32 x) { return ::acoshf(x); }
+inline f32 atanh(f32 x) { return ::atanhf(x); }
+
+// Rounding
+inline f32 ceil(f32 x)       { return ::ceilf(x); }
+inline f32 floor(f32 x)      { return ::floorf(x); }
+inline f32 mod(f32 x, f32 y) { return ::fmodf(x, y); }
+inline f32 truncate(f32 x)   { return ::truncf(x); }
+inline f32 round(f32 x)      { return ::roundf(x); }
+
+inline s32 sign(s32 x) { return x >= 0 ? +1 : -1; }
+inline s64 sign(s64 x) { return x >= 0 ? +1 : -1; }
+inline f32 sign(f32 x) { return x >= 0 ? +1 : -1; }
+
+// Other
+inline f32 abs(f32 x)
+{
+	u32 i = reinterpret_cast<const u32&>(x);
+	i &= 0x7FFFFFFFul;
+	return reinterpret_cast<const f32&>(i);
+}
+
+inline s8 abs(s8 x)
+{
+u8 i = reinterpret_cast<const u8&>(x);
+	i &= 0x7Fu;
+	return reinterpret_cast<const s8&>(i);
+}
+
+inline s16 abs(s16 x)
+{
+	u16 i = reinterpret_cast<const u16&>(x);
+	i &= 0x7FFFu;
+	return reinterpret_cast<const s16&>(i);
+}
+
+inline s32 abs(s32 x)
+{
+	u32 i = reinterpret_cast<const u32&>(x);
+	i &= 0x7FFFFFFFul;
+	return reinterpret_cast<const s32&>(i);
+}
+
+inline s64 abs(s64 x)
+{
+	u64 i = reinterpret_cast<const u64&>(x);
+	i &= 0x7FFFFFFFFFFFFFFFull;
+	return reinterpret_cast<const s64&>(i);
+}
+
+
+
+
+// Vector2 functions
+f32 dot(const Vector2& a, const Vector2& b)
+{
+	return a.x * b.x + a.y * b.y;
+}
+
+f32 cross(const Vector2& a, const Vector2& b)
+{
+	return a.x * b.y - a.y * b.x;
+}
+
+f32 magnitude(const Vector2& a)
+{
+	return math::sqrt(math::dot(a, a));
+}
+
+Vector2 normalize(const Vector2& a)
+{
+	f32 m = 1.0f / magnitude(a);
+	return a * m;
+}
+
+Vector2 hadamard_product(const Vector2& a, const Vector2& b)
+{
+	return {a.x * b.x, a.y * b.y};
+}
+
+// Vector3 functions
+f32 dot(const Vector3& a, const Vector3& b)
+{
+	return a.x * b.x + a.y * b.y + a.z * b.z;
+}
+
+Vector3 cross(const Vector3& a, const Vector3& b)
+{
+	return {
+	    a.y * b.z - b.y * a.z, // x
+	    a.z * b.x - b.z * a.x, // y
+	    a.x * b.y - b.x * a.y  // z
+	};
+}
+
+f32 magnitude(const Vector3& a)
+{
+	return math::sqrt(math::dot(a, a));
+}
+
+Vector3 normalize(const Vector3& a)
+{
+	f32 m = 1.0f / magnitude(a);
+	return a * m;
+}
+
+Vector3 hadamard_product(const Vector3& a, const Vector3& b)
+{
+	return {a.x * b.x, a.y * b.y, a.z * b.z};
+}
+
+// Vector4 functions
+f32 dot(const Vector4& a, const Vector4& b)
+{
+	return a.x*b.x + a.y*b.y + a.z*b.z + a.w*b.w;
+}
+
+f32 magnitude(const Vector4& a)
+{
+	return math::sqrt(math::dot(a, a));
+}
+
+Vector4 normalize(const Vector4& a)
+{
+	f32 m = 1.0f / magnitude(a);
+	return a * m;
+}
+
+Vector4 hadamard_product(const Vector4& a, const Vector4& b)
+{
+	return {a.x * b.x, a.y * b.y, a.z * b.z, a.w * b.w};
+}
+
+// Quaternion functions
+f32 dot(const Quaternion& a, const Quaternion& b)
+{
+	return math::dot(a.xyz, b.xyz) + a.w*b.w;
+}
+
+Quaternion cross(const Quaternion& a, const Quaternion& b)
+{
+	return {a.w * b.x + a.x * b.w + a.y * b.z - a.z * b.y,
+            a.w * b.y + a.y * b.w + a.z * b.x - a.x * b.z,
+            a.w * b.z + a.z * b.w + a.x * b.y - a.y * b.x,
+            a.w * b.w - a.x * b.x - a.y * b.y - a.z * b.z};
+}
+
+f32 magnitude(const Quaternion& a)
+{
+	return math::sqrt(math::dot(a, a));
+}
+
+Quaternion normalize(const Quaternion& a)
+{
+	f32 m = 1.0f / magnitude(a);
+	return a * m;
+}
+
+Quaternion conjugate(const Quaternion& a)
+{
+	return {-a.x, -a.y, -a.z, a.w};
+}
+
+Quaternion inverse(const Quaternion& a)
+{
+	f32 m = 1.0f / dot(a, a);
+	return math::conjugate(a) * m;
+}
+
+Vector3 operator*(const Quaternion& a, const Vector3& v) // Rotate v by q
+{
+	// return (q * Quaternion(v, 0) * conjugate(q)).xyz; // More Expensive
+	const Vector3 t = 2.0f * cross(a.xyz, v);
+	return (v + a.w * t + cross(a.xyz, t));
+}
+
+f32 quaternion_angle(const Quaternion& a)
+{
+	return 2.0f * math::acos(a.w);
+}
+
+Vector3 quaternion_axis(const Quaternion& a)
+{
+	f32 s2 = 1.0f - a.w * a.w;
+
+	if (s2 <= 0.0f)
+		return {0, 0, 1};
+
+	f32 invs2 = 1.0f / math::sqrt(s2);
+
+	return a.xyz * invs2;
+}
+
+Quaternion axis_angle(const Vector3& axis, f32 radians)
+{
+	Vector3 a = math::normalize(axis);
+	f32 s = math::sin(0.5f * radians);
+
+	Quaternion q;
+	q.xyz = a * s;
+	q.w = math::cos(0.5f * radians);
+
+	return q;
+}
+
+f32 quaternion_roll(const Quaternion& a)
+{
+	return math::atan2(2.0f * a.x * a.y + a.z * a.w,
+	                   a.x * a.x + a.w * a.w - a.y * a.y - a.z * a.z);
+}
+
+f32 quaternion_pitch(const Quaternion& a)
+{
+	return math::atan2(2.0f * a.y * a.z + a.w * a.x,
+	                   a.w * a.w - a.x * a.x - a.y * a.y + a.z * a.z);
+}
+
+f32 quaternion_yaw(const Quaternion& a)
+{
+	return math::asin(-2.0f * (a.x * a.z - a.w * a.y));
+
+}
+
+Euler_Angles quaternion_to_euler_angles(const Quaternion& a)
+{
+	return {quaternion_pitch(a), quaternion_yaw(a), quaternion_roll(a)};
+}
+
+Quaternion euler_angles_to_quaternion(const Euler_Angles& e,
+                                      const Vector3& x_axis,
+                                      const Vector3& y_axis,
+                                      const Vector3& z_axis)
+{
+	Quaternion p = axis_angle(x_axis, e.pitch);
+	Quaternion y = axis_angle(y_axis, e.yaw);
+	Quaternion r = axis_angle(z_axis, e.roll);
+
+	return y * p * r;
+}
+
+
+// Matrix4 functions
+Matrix4 transpose(const Matrix4& m)
+{
+	Matrix4 result;
+
+	for (usize i = 0; i < 4; i++)
+	{
+		for (usize j = 0; j < 4; j++)
+			result[i][j] = m[j][i];
+	}
+	return result;
+}
+
+f32 determinant(const Matrix4& m)
+{
+	f32 coef00 = m[2][2] * m[3][3] - m[3][2] * m[2][3];
+	f32 coef02 = m[1][2] * m[3][3] - m[3][2] * m[1][3];
+	f32 coef03 = m[1][2] * m[2][3] - m[2][2] * m[1][3];
+
+	f32 coef04 = m[2][1] * m[3][3] - m[3][1] * m[2][3];
+	f32 coef06 = m[1][1] * m[3][3] - m[3][1] * m[1][3];
+	f32 coef07 = m[1][1] * m[2][3] - m[2][1] * m[1][3];
+
+	f32 coef08 = m[2][1] * m[3][2] - m[3][1] * m[2][2];
+	f32 coef10 = m[1][1] * m[3][2] - m[3][1] * m[1][2];
+	f32 coef11 = m[1][1] * m[2][2] - m[2][1] * m[1][2];
+
+	f32 coef12 = m[2][0] * m[3][3] - m[3][0] * m[2][3];
+	f32 coef14 = m[1][0] * m[3][3] - m[3][0] * m[1][3];
+	f32 coef15 = m[1][0] * m[2][3] - m[2][0] * m[1][3];
+
+	f32 coef16 = m[2][0] * m[3][2] - m[3][0] * m[2][2];
+	f32 coef18 = m[1][0] * m[3][2] - m[3][0] * m[1][2];
+	f32 coef19 = m[1][0] * m[2][2] - m[2][0] * m[1][2];
+
+	f32 coef20 = m[2][0] * m[3][1] - m[3][0] * m[2][1];
+	f32 coef22 = m[1][0] * m[3][1] - m[3][0] * m[1][1];
+	f32 coef23 = m[1][0] * m[2][1] - m[2][0] * m[1][1];
+
+	Vector4 fac0 = {coef00, coef00, coef02, coef03};
+	Vector4 fac1 = {coef04, coef04, coef06, coef07};
+	Vector4 fac2 = {coef08, coef08, coef10, coef11};
+	Vector4 fac3 = {coef12, coef12, coef14, coef15};
+	Vector4 fac4 = {coef16, coef16, coef18, coef19};
+	Vector4 fac5 = {coef20, coef20, coef22, coef23};
+
+	Vector4 vec0 = {m[1][0], m[0][0], m[0][0], m[0][0]};
+	Vector4 vec1 = {m[1][1], m[0][1], m[0][1], m[0][1]};
+	Vector4 vec2 = {m[1][2], m[0][2], m[0][2], m[0][2]};
+	Vector4 vec3 = {m[1][3], m[0][3], m[0][3], m[0][3]};
+
+	Vector4 inv0 = vec1 * fac0 - vec2 * fac1 + vec3 * fac2;
+	Vector4 inv1 = vec0 * fac0 - vec2 * fac3 + vec3 * fac4;
+	Vector4 inv2 = vec0 * fac1 - vec1 * fac3 + vec3 * fac5;
+	Vector4 inv3 = vec0 * fac2 - vec1 * fac4 + vec2 * fac5;
+
+	Vector4 signA = {+1, -1, +1, -1};
+	Vector4 signB = {-1, +1, -1, +1};
+	Matrix4 inverse = {inv0 * signA, inv1 * signB, inv2 * signA, inv3 * signB};
+
+	Vector4 row0 = {inverse[0][0], inverse[1][0], inverse[2][0], inverse[3][0]};
+
+	Vector4 dot0 = m[0] * row0;
+	f32 dot1 = (dot0[0] + dot0[1]) + (dot0[2] + dot0[3]);
+	return dot1;
+}
+
+Matrix4 inverse(const Matrix4& m)
+{
+	f32 coef00 = m[2][2] * m[3][3] - m[3][2] * m[2][3];
+	f32 coef02 = m[1][2] * m[3][3] - m[3][2] * m[1][3];
+	f32 coef03 = m[1][2] * m[2][3] - m[2][2] * m[1][3];
+	f32 coef04 = m[2][1] * m[3][3] - m[3][1] * m[2][3];
+	f32 coef06 = m[1][1] * m[3][3] - m[3][1] * m[1][3];
+	f32 coef07 = m[1][1] * m[2][3] - m[2][1] * m[1][3];
+	f32 coef08 = m[2][1] * m[3][2] - m[3][1] * m[2][2];
+	f32 coef10 = m[1][1] * m[3][2] - m[3][1] * m[1][2];
+	f32 coef11 = m[1][1] * m[2][2] - m[2][1] * m[1][2];
+	f32 coef12 = m[2][0] * m[3][3] - m[3][0] * m[2][3];
+	f32 coef14 = m[1][0] * m[3][3] - m[3][0] * m[1][3];
+	f32 coef15 = m[1][0] * m[2][3] - m[2][0] * m[1][3];
+	f32 coef16 = m[2][0] * m[3][2] - m[3][0] * m[2][2];
+	f32 coef18 = m[1][0] * m[3][2] - m[3][0] * m[1][2];
+	f32 coef19 = m[1][0] * m[2][2] - m[2][0] * m[1][2];
+	f32 coef20 = m[2][0] * m[3][1] - m[3][0] * m[2][1];
+	f32 coef22 = m[1][0] * m[3][1] - m[3][0] * m[1][1];
+	f32 coef23 = m[1][0] * m[2][1] - m[2][0] * m[1][1];
+
+	Vector4 fac0 = {coef00, coef00, coef02, coef03};
+	Vector4 fac1 = {coef04, coef04, coef06, coef07};
+	Vector4 fac2 = {coef08, coef08, coef10, coef11};
+	Vector4 fac3 = {coef12, coef12, coef14, coef15};
+	Vector4 fac4 = {coef16, coef16, coef18, coef19};
+	Vector4 fac5 = {coef20, coef20, coef22, coef23};
+
+	Vector4 vec0 = {m[1][0], m[0][0], m[0][0], m[0][0]};
+	Vector4 vec1 = {m[1][1], m[0][1], m[0][1], m[0][1]};
+	Vector4 vec2 = {m[1][2], m[0][2], m[0][2], m[0][2]};
+	Vector4 vec3 = {m[1][3], m[0][3], m[0][3], m[0][3]};
+
+	Vector4 inv0 = vec1 * fac0 - vec2 * fac1 + vec3 * fac2;
+	Vector4 inv1 = vec0 * fac0 - vec2 * fac3 + vec3 * fac4;
+	Vector4 inv2 = vec0 * fac1 - vec1 * fac3 + vec3 * fac5;
+	Vector4 inv3 = vec0 * fac2 - vec1 * fac4 + vec2 * fac5;
+
+	Vector4 signA = {+1, -1, +1, -1};
+	Vector4 signB = {-1, +1, -1, +1};
+	Matrix4 inverse = {inv0 * signA, inv1 * signB, inv2 * signA, inv3 * signB};
+
+	Vector4 row0 = {inverse[0][0], inverse[1][0], inverse[2][0], inverse[3][0]};
+
+	Vector4 dot0 = m[0] * row0;
+	f32 dot1 = (dot0[0] + dot0[1]) + (dot0[2] + dot0[3]);
+
+	f32 oneOverDeterminant = 1.0f / dot1;
+
+	return inverse * oneOverDeterminant;
+}
+
+Matrix4 hadamard_product(const Matrix4& a, const Matrix4& b)
+{
+	Matrix4 result;
+
+	for (usize i = 0; i < 4; i++)
+		result[i] = a[i] * b[i];
+
+	return result;
+}
+
+Matrix4 quaternion_to_matrix4(const Quaternion& q)
+{
+	Matrix4 mat = MATRIX4_IDENTITY;
+
+	Quaternion a = math::normalize(q);
+
+	f32 xx = a.x * a.x;
+	f32 yy = a.y * a.y;
+	f32 zz = a.z * a.z;
+	f32 xy = a.x * a.y;
+	f32 xz = a.x * a.z;
+	f32 yz = a.y * a.z;
+	f32 wx = a.w * a.x;
+	f32 wy = a.w * a.y;
+	f32 wz = a.w * a.z;
+
+	mat[0][0] = 1.0f - 2.0f * (yy + zz);
+	mat[0][1] = 2.0f * (xy + wz);
+	mat[0][2] = 2.0f * (xz - wy);
+
+	mat[1][0] = 2.0f * (xy - wz);
+	mat[1][1] = 1.0f - 2.0f * (xx + zz);
+	mat[1][2] = 2.0f * (yz + wx);
+
+	mat[2][0] = 2.0f * (xz + wy);
+	mat[2][1] = 2.0f * (yz - wx);
+	mat[2][2] = 1.0f - 2.0f * (xx + yy);
+
+	return mat;
+}
+
+Quaternion matrix4_to_quaternion(const Matrix4& m)
+{
+	f32 four_x_squared_minus_1 = m[0][0] - m[1][1] - m[2][2];
+	f32 four_y_squared_minus_1 = m[1][1] - m[0][0] - m[2][2];
+	f32 four_z_squared_minus_1 = m[2][2] - m[0][0] - m[1][1];
+	f32 four_w_squared_minus_1 = m[0][0] + m[1][1] + m[2][2];
+
+	s32 biggestIndex = 0;
+	f32 four_biggest_squared_minus_1 = four_w_squared_minus_1;
+	if (four_x_squared_minus_1 > four_biggest_squared_minus_1)
+	{
+		four_biggest_squared_minus_1 = four_x_squared_minus_1;
+		biggestIndex             = 1;
+	}
+	if (four_y_squared_minus_1 > four_biggest_squared_minus_1)
+	{
+		four_biggest_squared_minus_1 = four_y_squared_minus_1;
+		biggestIndex             = 2;
+	}
+	if (four_z_squared_minus_1 > four_biggest_squared_minus_1)
+	{
+		four_biggest_squared_minus_1 = four_z_squared_minus_1;
+		biggestIndex             = 3;
+	}
+
+	f32 biggestVal = math::sqrt(four_biggest_squared_minus_1 + 1.0f) * 0.5f;
+	f32 mult       = 0.25f / biggestVal;
+
+	Quaternion q = QUATERNION_IDENTITY;
+
+	switch (biggestIndex)
+	{
+	case 0:
+	{
+		q.w = biggestVal;
+		q.x = (m[1][2] - m[2][1]) * mult;
+		q.y = (m[2][0] - m[0][2]) * mult;
+		q.z = (m[0][1] - m[1][0]) * mult;
+	}
+	break;
+	case 1:
+	{
+		q.w = (m[1][2] - m[2][1]) * mult;
+		q.x = biggestVal;
+		q.y = (m[0][1] + m[1][0]) * mult;
+		q.z = (m[2][0] + m[0][2]) * mult;
+	}
+	break;
+	case 2:
+	{
+		q.w = (m[2][0] - m[0][2]) * mult;
+		q.x = (m[0][1] + m[1][0]) * mult;
+		q.y = biggestVal;
+		q.z = (m[1][2] + m[2][1]) * mult;
+	}
+	break;
+	case 3:
+	{
+		q.w = (m[0][1] - m[1][0]) * mult;
+		q.x = (m[2][0] + m[0][2]) * mult;
+		q.y = (m[1][2] + m[2][1]) * mult;
+		q.z = biggestVal;
+	}
+	break;
+	default: // Should never actually get here. Just for sanities sake.
+	{
+		GB_ASSERT(false, "How did you get here?!");
+	}
+	break;
+	}
+
+	return q;
+}
+
+
+Matrix4 translate(const Vector3& v)
+{
+	Matrix4 result = MATRIX4_IDENTITY;
+	result[3].xyz = v;
+	result[3].w = 1;
+	return result;
+}
+
+Matrix4 rotate(const Vector3& v, f32 radians)
+{
+	const f32 c = math::cos(radians);
+	const f32 s = math::sin(radians);
+
+	const Vector3 axis = math::normalize(v);
+	const Vector3 t    = (1.0f - c) * axis;
+
+	Matrix4 rot = MATRIX4_IDENTITY;
+	rot[0][0]   = c + t.x * axis.x;
+	rot[0][1]   = 0 + t.x * axis.y + s * axis.z;
+	rot[0][2]   = 0 + t.x * axis.z - s * axis.y;
+	rot[0][3]   = 0;
+
+	rot[1][0] = 0 + t.y * axis.x - s * axis.z;
+	rot[1][1] = c + t.y * axis.y;
+	rot[1][2] = 0 + t.y * axis.z + s * axis.x;
+	rot[1][3] = 0;
+
+	rot[2][0] = 0 + t.z * axis.x + s * axis.y;
+	rot[2][1] = 0 + t.z * axis.y - s * axis.x;
+	rot[2][2] = c + t.z * axis.z;
+	rot[2][3] = 0;
+
+	return rot;
+}
+
+Matrix4 scale(const Vector3& v)
+{
+	return { v.x,   0,   0, 0,
+	           0, v.y,   0, 0,
+	           0,   0, v.z, 0,
+	           0,   0,   0, 1 };
+}
+
+Matrix4 ortho(f32 left, f32 right, f32 bottom, f32 top)
+{
+	Matrix4 result = MATRIX4_IDENTITY;
+
+	result[0][0] = 2.0f / (right - left);
+	result[1][1] = 2.0f / (top - bottom);
+	result[2][2] = -1.0f;
+	result[3][1] = -(right + left) / (right - left);
+	result[3][1] = -(top + bottom) / (top - bottom);
+
+	return result;
+}
+
+Matrix4 ortho(f32 left, f32 right, f32 bottom, f32 top, f32 z_near, f32 z_far)
+{
+	Matrix4 result = MATRIX4_IDENTITY;
+
+	result[0][0] = 2.0f / (right - left);
+	result[1][1] = 2.0f / (top - bottom);
+	result[2][2] = -2.0f / (z_far - z_near);
+	result[3][0] = -(right + left) / (right - left);
+	result[3][1] = -(top + bottom) / (top - bottom);
+	result[3][2] = -(z_far + z_near) / (z_far - z_near);
+
+	return result;
+}
+
+Matrix4 perspective(f32 fovy_radians, f32 aspect, f32 z_near, f32 z_far)
+{
+	GB_ASSERT(math::abs(aspect) > 0.0f,
+	          "math::perspective `fovy_radians` is %f", fovy_radians);
+
+	f32 tan_half_fovy = math::tan(0.5f * fovy_radians);
+
+	Matrix4 result = {};
+	result[0][0]   = 1.0f / (aspect * tan_half_fovy);
+	result[1][1]   = 1.0f / (tan_half_fovy);
+	result[2][2]   = -(z_far + z_near) / (z_far - z_near);
+	result[2][3]   = -1.0f;
+	result[3][2]   = -2.0f * z_far * z_near / (z_far - z_near);
+
+	return result;
+}
+
+Matrix4 infinite_perspective(f32 fovy_radians, f32 aspect, f32 z_near)
+{
+	f32 range  = math::tan(0.5f * fovy_radians) * z_near;
+	f32 left   = -range * aspect;
+	f32 right  =  range * aspect;
+	f32 bottom = -range;
+	f32 top    =  range;
+
+	Matrix4 result = {};
+
+	result[0][0] = (2.0f * z_near) / (right - left);
+	result[1][1] = (2.0f * z_near) / (top - bottom);
+	result[2][2] = -1.0f;
+	result[2][3] = -1.0f;
+	result[3][2] = -2.0f * z_near;
+
+	return result;
+}
+
+
+Matrix4
+look_at_matrix4(const Vector3& eye, const Vector3& center, const Vector3& up)
+{
+	const Vector3 f = math::normalize(center - eye);
+	const Vector3 s = math::normalize(math::cross(f, up));
+	const Vector3 u = math::cross(s, f);
+
+	Matrix4 result = MATRIX4_IDENTITY;
+	result[0][0]   = +s.x;
+	result[1][0]   = +s.y;
+	result[2][0]   = +s.z;
+
+	result[0][1] = +u.x;
+	result[1][1] = +u.y;
+	result[2][1] = +u.z;
+
+	result[0][2] = -f.x;
+	result[1][2] = -f.y;
+	result[2][2] = -f.z;
+
+	result[3][0] = -math::dot(s, eye);
+	result[3][1] = -math::dot(u, eye);
+	result[3][2] = +math::dot(f, eye);
+
+	return result;
+}
+
+
+Quaternion
+look_at_quaternion(const Vector3& eye, const Vector3& center, const Vector3& up)
+{
+	const f32 similar = 0.001f;
+
+	if (magnitude(center - eye) < similar)
+		return QUATERNION_IDENTITY; // You cannot look at where you are!
+
+	// TODO(bill): Implement using just quaternions
+	return matrix4_to_quaternion(look_at_matrix4(eye, center, up));
+}
+
+
+
+
+} // namespace math
+} // namespace gb
+
+#endif // GB_IMPLEMENTATION