raymath.h

/**********************************************************************************************
*
*   raymath v1.5 - Math functions to work with GETS(Vector2), GETS(Vector3), GETS(Matrix) and GETS(Quaternion)s
*
*   CONVENTIONS:
*     - GETS(Matrix) structure is defined as row-major (memory layout) but parameters naming AND all
*       math operations performed by the library consider the structure as it was column-major
*       It is like transposed versions of the matrices are used for all the maths
*       It benefits some functions making them cache-friendly and also avoids matrix
*       transpositions sometimes required by OpenGL
*       Example: In memory order, row0 is [m0 m4 m8 m12] but in semantic math row0 is [m0 m1 m2 m3]
*     - Functions are always self-contained, no function use another raymath function inside,
*       required code is directly re-implemented inside
*     - Functions input parameters are always received by value (2 unavoidable exceptions)
*     - Functions use always a "result" variable for return
*     - Functions are always defined inline
*     - Angles are always in radians (DEG2RAD/RAD2DEG macros provided for convenience)
*     - No compound literals used to make sure libray is compatible with C++
*
*   CONFIGURATION:
*       #define RAYMATH_IMPLEMENTATION
*           Generates the implementation of the library into the included file.
*           If not defined, the library is in header only mode and can be included in other headers
*           or source files without problems. But only ONE file should hold the implementation.
*
*       #define RAYMATH_STATIC_INLINE
*           Define static inline functions code, so #include header suffices for use.
*           This may use up lots of memory.
*
*
*   LICENSE: zlib/libpng
*
*   Copyright (c) 2015-2024 Ramon Santamaria (@raysan5)
*
*   This software is provided "as-is", without any express or implied warranty. In no event
*   will the authors be held liable for any damages arising from the use of this software.
*
*   Permission is granted to anyone to use this software for any purpose, including commercial
*   applications, and to alter it and redistribute it freely, subject to the following restrictions:
*
*     1. The origin of this software must not be misrepresented; you must not claim that you
*     wrote the original software. If you use this software in a product, an acknowledgment
*     in the product documentation would be appreciated but is not required.
*
*     2. Altered source versions must be plainly marked as such, and must not be misrepresented
*     as being the original software.
*
*     3. This notice may not be removed or altered from any source distribution.
*
**********************************************************************************************/

#ifndef RAYMATH_H
#define RAYMATH_H

#include "m.h"
#include <string.h>
#include <stdlib.h>

#ifndef GETS
#ifndef RL_NO_STRUCT
#define GETS(x) x
#else
#define GETS(x) rl##x
#endif
#endif

#if defined(RAYMATH_IMPLEMENTATION) && defined(RAYMATH_STATIC_INLINE)
#error "Specifying both RAYMATH_IMPLEMENTATION and RAYMATH_STATIC_INLINE is contradictory"
#endif

// Function specifiers definition
#if defined(RAYMATH_IMPLEMENTATION)
#if defined(_WIN32) && defined(BUILD_LIBTYPE_SHARED)
#define RMAPI __declspec(dllexport) extern inline // We are building raylib as a Win32 shared library (.dll)
#elif defined(BUILD_LIBTYPE_SHARED)
#define RMAPI __attribute__((visibility("default"))) // We are building raylib as a Unix shared library (.so/.dylib)
#elif defined(_WIN32) && defined(USE_LIBTYPE_SHARED)
#define RMAPI __declspec(dllimport)         // We are using raylib as a Win32 shared library (.dll)
#else
#define RMAPI extern inline // Provide external definition
#endif
#elif defined(RAYMATH_STATIC_INLINE)
#define RMAPI static inline // Functions may be inlined, no external out-of-line definition
#else
#if defined(__TINYC__)
#define RMAPI static inline // plain inline not supported by tinycc (See issue #435)
#else
#define RMAPI inline        // Functions may be inlined or external definition used
#endif
#endif

//----------------------------------------------------------------------------------
// Defines and Macros
//----------------------------------------------------------------------------------
#ifndef PI
#define PI 3.14159265358979323846f
#endif

#ifndef EPSILON
#define EPSILON 0.000001f
#endif

#ifndef DEG2RAD
#define DEG2RAD (PI/180.0f)
#endif

#ifndef RAD2DEG
#define RAD2DEG (180.0f/PI)
#endif

// Get float vector for GETS(Matrix)

// Get float vector for GETS(Vector3)
#ifndef Vector3ToFloat
#define Vector3ToFloat(vec) (Vector3ToFloatV(vec).v)
#endif

//----------------------------------------------------------------------------------
// Types and Structures Definition
//----------------------------------------------------------------------------------
#if !defined(RL_VECTOR2_TYPE)
// GETS(Vector2) type
typedef struct
GETS(Vector2)
{
  float x;
  float y;
}
GETS(Vector2);
#define RL_VECTOR2_TYPE
#endif

#if !defined(RL_VECTOR3_TYPE)
// GETS(Vector3) type
typedef struct
GETS(Vector3)
{
  float x;
  float y;
  float z;
}
GETS(Vector3);
#define RL_VECTOR3_TYPE
#endif

#if !defined(RL_VECTOR4_TYPE)
// Vector4 type
typedef struct
GETS(Vector4)
{
  float x;
  float y;
  float z;
  float w;
}
GETS(Vector4);
#define RL_VECTOR4_TYPE
#endif

#if !defined(RL_QUATERNION_TYPE)
// GETS(Quaternion) type
typedef Vector4 GETS(Quaternion);
#define RL_QUATERNION_TYPE
#endif

#if !defined(RL_MATRIX_TYPE)
// GETS(Matrix) type (OpenGL style 4x4 - right handed, column major)
typedef struct
GETS(Matrix)
{
  float m0, m4, m8, m12;      // GETS(Matrix) first row (4 components)
  float m1, m5, m9, m13;      // GETS(Matrix) second row (4 components)
  float m2, m6, m10, m14;     // GETS(Matrix) third row (4 components)
  float m3, m7, m11, m15;     // GETS(Matrix) fourth row (4 components)
}
GETS(Matrix);
#define RL_MATRIX_TYPE
#endif

// NOTE: Helper types to be used instead of array return types for *ToFloat functions
typedef struct float3 {
  float v[3];
} float3;

typedef struct float16 {
  float v[16];
} float16;

#include <math.h>       // Required for: sinf(), cosf(), tan(), atan2f(), sqrtf(), floor(), fminf(), fmaxf(), fabsf()

//----------------------------------------------------------------------------------
// Module Functions Definition - Utils math
//----------------------------------------------------------------------------------

// Clamp float value
RMAPI float
Clamp(float value, float min, float max)
{
  float result = (value < min) ? min : value;

  if (result > max) result = max;

  return result;
}

// Calculate linear interpolation between two floats
RMAPI float
Lerp(float start, float end, float amount)
{
  float result = start + amount*(end - start);

  return result;
}

// Normalize input value within input range
RMAPI float
Normalize(float value, float start, float end)
{
  float result = (value - start)/(end - start);

  return result;
}

// Remap input value within input range to output range
RMAPI float
Remap(float value, float inputStart, float inputEnd, float outputStart, float outputEnd)
{
  float result = (value - inputStart)/(inputEnd - inputStart)*(outputEnd - outputStart) + outputStart;

  return result;
}

// Wrap input value from min to max
RMAPI float
Wrap(float value, float min, float max)
{
  float result = value - (max - min)*floorf((value - min)/(max - min));

  return result;
}

// Check whether two given floats are almost equal
RMAPI int
FloatEquals(float x, float y)
{
#if !defined(EPSILON)
#define EPSILON 0.000001f
#endif

  int result = (fabsf(x - y)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(x), fabsf(y))));

  return result;
}

//----------------------------------------------------------------------------------
// Module Functions Definition - GETS(Vector2) math
//----------------------------------------------------------------------------------

// Vector with components value 0.0f
RMAPI
GETS(Vector2) Vector2Zero(void)
{
  GETS(Vector2) result = { 0.0f, 0.0f };

  return result;
}

// Vector with components value 1.0f
RMAPI
GETS(Vector2) Vector2One(void)
{
  GETS(Vector2) result = { 1.0f, 1.0f };

  return result;
}

// Add two vectors (v1 + v2)
RMAPI
GETS(Vector2) Vector2Add(GETS(Vector2) v1, GETS(Vector2) v2)
{
  GETS(Vector2) result = { v1.x + v2.x, v1.y + v2.y };

  return result;
}

// Add vector and float value
RMAPI
GETS(Vector2) Vector2AddValue(GETS(Vector2) v, float add)
{
  GETS(Vector2) result = { v.x + add, v.y + add };

  return result;
}

// Subtract two vectors (v1 - v2)
RMAPI
GETS(Vector2) Vector2Subtract(GETS(Vector2) v1, GETS(Vector2) v2)
{
  GETS(Vector2) result = { v1.x - v2.x, v1.y - v2.y };

  return result;
}

// Subtract vector by float value
RMAPI
GETS(Vector2) Vector2SubtractValue(GETS(Vector2) v, float sub)
{
  GETS(Vector2) result = { v.x - sub, v.y - sub };

  return result;
}

// Calculate vector length
RMAPI float
Vector2Length(GETS(Vector2) v)
{
  float result = sqrtf((v.x*v.x) + (v.y*v.y));

  return result;
}

// Calculate vector square length
RMAPI float
Vector2LengthSqr(GETS(Vector2) v)
{
  float result = (v.x*v.x) + (v.y*v.y);

  return result;
}

// Calculate two vectors dot product
RMAPI float
Vector2DotProduct(GETS(Vector2) v1, GETS(Vector2) v2)
{
  float result = (v1.x*v2.x + v1.y*v2.y);

  return result;
}

// Calculate distance between two vectors
RMAPI float
Vector2Distance(GETS(Vector2) v1, GETS(Vector2) v2)
{
  float result = sqrtf((v1.x - v2.x)*(v1.x - v2.x) + (v1.y - v2.y)*(v1.y - v2.y));

  return result;
}

// Calculate square distance between two vectors
RMAPI float
Vector2DistanceSqr(GETS(Vector2) v1, GETS(Vector2) v2)
{
  float result = ((v1.x - v2.x)*(v1.x - v2.x) + (v1.y - v2.y)*(v1.y - v2.y));

  return result;
}

// Calculate angle between two vectors
// NOTE: Angle is calculated from origin point (0, 0)
RMAPI float
Vector2Angle(GETS(Vector2) v1, GETS(Vector2) v2)
{
  float result = 0.0f;

  float dot = v1.x*v2.x + v1.y*v2.y;
  float det = v1.x*v2.y - v1.y*v2.x;

  result = atan2f(det, dot);

  return result;
}

// Calculate angle defined by a two vectors line
// NOTE: Parameters need to be normalized
// Current implementation should be aligned with glm::angle
RMAPI float
Vector2LineAngle(GETS(Vector2) start, GETS(Vector2) end)
{
  float result = 0.0f;

  // TODO(10/9/2023): Currently angles move clockwise, determine if this is wanted behavior
  result = -atan2f(end.y - start.y, end.x - start.x);

  return result;
}

// Scale vector (multiply by value)
RMAPI
GETS(Vector2) Vector2Scale(GETS(Vector2) v, float scale)
{
  GETS(Vector2) result = { v.x*scale, v.y*scale };

  return result;
}

// Multiply vector by vector
RMAPI
GETS(Vector2) Vector2Multiply(GETS(Vector2) v1, GETS(Vector2) v2)
{
  GETS(Vector2) result = { v1.x*v2.x, v1.y*v2.y };

  return result;
}

// Negate vector
RMAPI
GETS(Vector2) Vector2Negate(GETS(Vector2) v)
{
  GETS(Vector2) result = { -v.x, -v.y };

  return result;
}

// Divide vector by vector
RMAPI
GETS(Vector2) Vector2Divide(GETS(Vector2) v1, GETS(Vector2) v2)
{
  GETS(Vector2) result = { v1.x/v2.x, v1.y/v2.y };

  return result;
}

// Normalize provided vector
RMAPI
GETS(Vector2) Vector2Normalize(GETS(Vector2) v)
{
  GETS(Vector2) result = { 0 };
  float length = sqrtf((v.x*v.x) + (v.y*v.y));

  if (length > 0) {
    float ilength = 1.0f/length;
    result.x = v.x*ilength;
    result.y = v.y*ilength;
  }

  return result;
}

// Transforms a GETS(Vector2) by a given GETS(Matrix)
RMAPI
GETS(Vector2) Vector2Transform(GETS(Vector2) v, GETS(Matrix) mat)
{
  GETS(Vector2) result = { 0 };

  float x = v.x;
  float y = v.y;
  float z = 0;

  result.x = mat.m0*x + mat.m4*y + mat.m8*z + mat.m12;
  result.y = mat.m1*x + mat.m5*y + mat.m9*z + mat.m13;

  return result;
}

// Calculate linear interpolation between two vectors
RMAPI
GETS(Vector2) Vector2Lerp(GETS(Vector2) v1, GETS(Vector2) v2, float amount)
{
  GETS(Vector2) result = { 0 };

  result.x = v1.x + amount*(v2.x - v1.x);
  result.y = v1.y + amount*(v2.y - v1.y);

  return result;
}

// Calculate reflected vector to normal
RMAPI
GETS(Vector2) Vector2Reflect(GETS(Vector2) v, GETS(Vector2) normal)
{
  GETS(Vector2) result = { 0 };

  float dotProduct = (v.x*normal.x + v.y*normal.y); // Dot product

  result.x = v.x - (2.0f*normal.x)*dotProduct;
  result.y = v.y - (2.0f*normal.y)*dotProduct;

  return result;
}

// Get min value for each pair of components
RMAPI
GETS(Vector2) Vector2Min(GETS(Vector2) v1, GETS(Vector2) v2)
{
  GETS(Vector2) result = { 0 };

  result.x = fminf(v1.x, v2.x);
  result.y = fminf(v1.y, v2.y);

  return result;
}

// Get max value for each pair of components
RMAPI
GETS(Vector2) Vector2Max(GETS(Vector2) v1, GETS(Vector2) v2)
{
  GETS(Vector2) result = { 0 };

  result.x = fmaxf(v1.x, v2.x);
  result.y = fmaxf(v1.y, v2.y);

  return result;
}

// Rotate vector by angle
RMAPI
GETS(Vector2) Vector2Rotate(GETS(Vector2) v, float angle)
{
  GETS(Vector2) result = { 0 };

  float cosres = cosf(angle);
  float sinres = sinf(angle);

  result.x = v.x*cosres - v.y*sinres;
  result.y = v.x*sinres + v.y*cosres;

  return result;
}

// Move Vector towards target
RMAPI
GETS(Vector2) Vector2MoveTowards(GETS(Vector2) v, GETS(Vector2) target, float maxDistance)
{
  GETS(Vector2) result = { 0 };

  float dx = target.x - v.x;
  float dy = target.y - v.y;
  float value = (dx*dx) + (dy*dy);

  if ((value == 0) || ((maxDistance >= 0) && (value <= maxDistance*maxDistance))) return target;

  float dist = sqrtf(value);

  result.x = v.x + dx/dist*maxDistance;
  result.y = v.y + dy/dist*maxDistance;

  return result;
}

// Invert the given vector
RMAPI
GETS(Vector2) Vector2Invert(GETS(Vector2) v)
{
  GETS(Vector2) result = { 1.0f/v.x, 1.0f/v.y };

  return result;
}

// Clamp the components of the vector between
// min and max values specified by the given vectors
RMAPI
GETS(Vector2) Vector2Clamp(GETS(Vector2) v, GETS(Vector2) min, GETS(Vector2) max)
{
  GETS(Vector2) result = { 0 };

  result.x = fminf(max.x, fmaxf(min.x, v.x));
  result.y = fminf(max.y, fmaxf(min.y, v.y));

  return result;
}

// Clamp the magnitude of the vector between two min and max values
RMAPI
GETS(Vector2) Vector2ClampValue(GETS(Vector2) v, float min, float max)
{
  GETS(Vector2) result = v;

  float length = (v.x*v.x) + (v.y*v.y);
  if (length > 0.0f) {
    length = sqrtf(length);

    float scale = 1;    // By default, 1 as the neutral element.
    if (length < min) {
      scale = min/length;
    } else if (length > max) {
      scale = max/length;
    }

    result.x = v.x*scale;
    result.y = v.y*scale;
  }

  return result;
}

// Check whether two given vectors are almost equal
RMAPI int
Vector2Equals(GETS(Vector2) p, GETS(Vector2) q)
{
#if !defined(EPSILON)
#define EPSILON 0.000001f
#endif

  int result = ((fabsf(p.x - q.x)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.x), fabsf(q.x))))) &&
               ((fabsf(p.y - q.y)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.y), fabsf(q.y)))));

  return result;
}

// Compute the direction of a refracted ray
// v: normalized direction of the incoming ray
// n: normalized normal vector of the interface of two optical media
// r: ratio of the refractive index of the medium from where the ray comes
//    to the refractive index of the medium on the other side of the surface
RMAPI
GETS(Vector2) Vector2Refract(GETS(Vector2) v, GETS(Vector2) n, float r)
{
  GETS(Vector2) result = { 0 };

  float dot = v.x*n.x + v.y*n.y;
  float d = 1.0f - r*r*(1.0f - dot*dot);

  if (d >= 0.0f) {
    d = sqrtf(d);
    v.x = r*v.x - (r*dot + d)*n.x;
    v.y = r*v.y - (r*dot + d)*n.y;

    result = v;
  }

  return result;
}


//----------------------------------------------------------------------------------
// Module Functions Definition - GETS(Vector3) math
//----------------------------------------------------------------------------------

// Vector with components value 0.0f
RMAPI
GETS(Vector3) Vector3Zero(void)
{
  GETS(Vector3) result = { 0.0f, 0.0f, 0.0f };

  return result;
}

// Vector with components value 1.0f
RMAPI
GETS(Vector3) Vector3One(void)
{
  GETS(Vector3) result = { 1.0f, 1.0f, 1.0f };

  return result;
}

// Add two vectors
RMAPI
GETS(Vector3) Vector3Add(GETS(Vector3) v1, GETS(Vector3) v2)
{
  GETS(Vector3) result = { v1.x + v2.x, v1.y + v2.y, v1.z + v2.z };

  return result;
}

// Add vector and float value
RMAPI
GETS(Vector3) Vector3AddValue(GETS(Vector3) v, float add)
{
  GETS(Vector3) result = { v.x + add, v.y + add, v.z + add };

  return result;
}

// Subtract two vectors
RMAPI
GETS(Vector3) Vector3Subtract(GETS(Vector3) v1, GETS(Vector3) v2)
{
  GETS(Vector3) result = { v1.x - v2.x, v1.y - v2.y, v1.z - v2.z };

  return result;
}

// Subtract vector by float value
RMAPI
GETS(Vector3) Vector3SubtractValue(GETS(Vector3) v, float sub)
{
  GETS(Vector3) result = { v.x - sub, v.y - sub, v.z - sub };

  return result;
}

// Multiply vector by scalar
RMAPI
GETS(Vector3) Vector3Scale(GETS(Vector3) v, float scalar)
{
  GETS(Vector3) result = { v.x*scalar, v.y*scalar, v.z*scalar };

  return result;
}

// Multiply vector by vector
RMAPI
GETS(Vector3) Vector3Multiply(GETS(Vector3) v1, GETS(Vector3) v2)
{
  GETS(Vector3) result = { v1.x*v2.x, v1.y*v2.y, v1.z*v2.z };

  return result;
}

// Calculate two vectors cross product
RMAPI
GETS(Vector3) Vector3CrossProduct(GETS(Vector3) v1, GETS(Vector3) v2)
{
  GETS(Vector3) result = { v1.y*v2.z - v1.z*v2.y, v1.z*v2.x - v1.x*v2.z, v1.x*v2.y - v1.y*v2.x };

  return result;
}

// Calculate one vector perpendicular vector
RMAPI
GETS(Vector3) Vector3Perpendicular(GETS(Vector3) v)
{
  GETS(Vector3) result = { 0 };

  float min = fabsf(v.x);
  GETS(Vector3) cardinalAxis = {1.0f, 0.0f, 0.0f};

  if (fabsf(v.y) < min) {
    min = fabsf(v.y);
    GETS(Vector3) tmp = {0.0f, 1.0f, 0.0f};
    cardinalAxis = tmp;
  }

  if (fabsf(v.z) < min) {
    GETS(Vector3) tmp = {0.0f, 0.0f, 1.0f};
    cardinalAxis = tmp;
  }

  // Cross product between vectors
  result.x = v.y*cardinalAxis.z - v.z*cardinalAxis.y;
  result.y = v.z*cardinalAxis.x - v.x*cardinalAxis.z;
  result.z = v.x*cardinalAxis.y - v.y*cardinalAxis.x;

  return result;
}

// Calculate vector length
RMAPI float
Vector3Length(const GETS(Vector3) v)
{
  float result = sqrtf(v.x*v.x + v.y*v.y + v.z*v.z);

  return result;
}

// Calculate vector square length
RMAPI float
Vector3LengthSqr(const GETS(Vector3) v)
{
  float result = v.x*v.x + v.y*v.y + v.z*v.z;

  return result;
}

// Calculate two vectors dot product
RMAPI float
Vector3DotProduct(GETS(Vector3) v1, GETS(Vector3) v2)
{
  float result = (v1.x*v2.x + v1.y*v2.y + v1.z*v2.z);

  return result;
}

// Calculate distance between two vectors
RMAPI float
Vector3Distance(GETS(Vector3) v1, GETS(Vector3) v2)
{
  float result = 0.0f;

  float dx = v2.x - v1.x;
  float dy = v2.y - v1.y;
  float dz = v2.z - v1.z;
  result = sqrtf(dx*dx + dy*dy + dz*dz);

  return result;
}

// Calculate square distance between two vectors
RMAPI float
Vector3DistanceSqr(GETS(Vector3) v1, GETS(Vector3) v2)
{
  float result = 0.0f;

  float dx = v2.x - v1.x;
  float dy = v2.y - v1.y;
  float dz = v2.z - v1.z;
  result = dx*dx + dy*dy + dz*dz;

  return result;
}

// Calculate angle between two vectors
RMAPI float
Vector3Angle(GETS(Vector3) v1, GETS(Vector3) v2)
{
  float result = 0.0f;

  GETS(Vector3) cross = { v1.y*v2.z - v1.z*v2.y, v1.z*v2.x - v1.x*v2.z, v1.x*v2.y - v1.y*v2.x };
  float len = sqrtf(cross.x*cross.x + cross.y*cross.y + cross.z*cross.z);
  float dot = (v1.x*v2.x + v1.y*v2.y + v1.z*v2.z);
  result = atan2f(len, dot);

  return result;
}

// Negate provided vector (invert direction)
RMAPI
GETS(Vector3) Vector3Negate(GETS(Vector3) v)
{
  GETS(Vector3) result = { -v.x, -v.y, -v.z };

  return result;
}

// Divide vector by vector
RMAPI
GETS(Vector3) Vector3Divide(GETS(Vector3) v1, GETS(Vector3) v2)
{
  GETS(Vector3) result = { v1.x/v2.x, v1.y/v2.y, v1.z/v2.z };

  return result;
}

// Normalize provided vector
RMAPI
GETS(Vector3) Vector3Normalize(GETS(Vector3) v)
{
  GETS(Vector3) result = v;

  float length = sqrtf(v.x*v.x + v.y*v.y + v.z*v.z);
  if (length != 0.0f) {
    float ilength = 1.0f/length;

    result.x *= ilength;
    result.y *= ilength;
    result.z *= ilength;
  }

  return result;
}

//Calculate the projection of the vector v1 on to v2
RMAPI
GETS(Vector3) Vector3Project(GETS(Vector3) v1, GETS(Vector3) v2)
{
  GETS(Vector3) result = { 0 };

  float v1dv2 = (v1.x*v2.x + v1.y*v2.y + v1.z*v2.z);
  float v2dv2 = (v2.x*v2.x + v2.y*v2.y + v2.z*v2.z);

  float mag = v1dv2/v2dv2;

  result.x = v2.x*mag;
  result.y = v2.y*mag;
  result.z = v2.z*mag;

  return result;
}

//Calculate the rejection of the vector v1 on to v2
RMAPI
GETS(Vector3) Vector3Reject(GETS(Vector3) v1, GETS(Vector3) v2)
{
  GETS(Vector3) result = { 0 };

  float v1dv2 = (v1.x*v2.x + v1.y*v2.y + v1.z*v2.z);
  float v2dv2 = (v2.x*v2.x + v2.y*v2.y + v2.z*v2.z);

  float mag = v1dv2/v2dv2;

  result.x = v1.x - (v2.x*mag);
  result.y = v1.y - (v2.y*mag);
  result.z = v1.z - (v2.z*mag);

  return result;
}

// Orthonormalize provided vectors
// Makes vectors normalized and orthogonal to each other
// Gram-Schmidt function implementation
RMAPI void
Vector3OrthoNormalize(GETS(Vector3) *v1, GETS(Vector3) *v2)
{
  float length = 0.0f;
  float ilength = 0.0f;

  // GETS(Vector3)Normalize(*v1);
  GETS(Vector3) v = *v1;
  length = sqrtf(v.x*v.x + v.y*v.y + v.z*v.z);
  if (length == 0.0f) length = 1.0f;
  ilength = 1.0f/length;
  v1->x *= ilength;
  v1->y *= ilength;
  v1->z *= ilength;

  // GETS(Vector3)CrossProduct(*v1, *v2)
  GETS(Vector3) vn1 = { v1->y*v2->z - v1->z*v2->y, v1->z*v2->x - v1->x*v2->z, v1->x*v2->y - v1->y*v2->x };

  // GETS(Vector3)Normalize(vn1);
  v = vn1;
  length = sqrtf(v.x*v.x + v.y*v.y + v.z*v.z);
  if (length == 0.0f) length = 1.0f;
  ilength = 1.0f/length;
  vn1.x *= ilength;
  vn1.y *= ilength;
  vn1.z *= ilength;

  // GETS(Vector3)CrossProduct(vn1, *v1)
  GETS(Vector3) vn2 = { vn1.y*v1->z - vn1.z*v1->y, vn1.z*v1->x - vn1.x*v1->z, vn1.x*v1->y - vn1.y*v1->x };

  *v2 = vn2;
}

// Transforms a GETS(Vector3) by a given GETS(Matrix)
RMAPI
GETS(Vector3) Vector3Transform(GETS(Vector3) v, GETS(Matrix) mat)
{
  GETS(Vector3) result = { 0 };

  float x = v.x;
  float y = v.y;
  float z = v.z;

  result.x = mat.m0*x + mat.m4*y + mat.m8*z + mat.m12;
  result.y = mat.m1*x + mat.m5*y + mat.m9*z + mat.m13;
  result.z = mat.m2*x + mat.m6*y + mat.m10*z + mat.m14;

  return result;
}

// Transform a vector by quaternion rotation
RMAPI
GETS(Vector3) Vector3RotateByQuaternion(GETS(Vector3) v, GETS(Quaternion) q)
{
  GETS(Vector3) result = { 0 };

  result.x = v.x*(q.x*q.x + q.w*q.w - q.y*q.y - q.z*q.z) + v.y*(2*q.x*q.y - 2*q.w*q.z) + v.z*(2*q.x*q.z + 2*q.w*q.y);
  result.y = v.x*(2*q.w*q.z + 2*q.x*q.y) + v.y*(q.w*q.w - q.x*q.x + q.y*q.y - q.z*q.z) + v.z*(-2*q.w*q.x + 2*q.y*q.z);
  result.z = v.x*(-2*q.w*q.y + 2*q.x*q.z) + v.y*(2*q.w*q.x + 2*q.y*q.z)+ v.z*(q.w*q.w - q.x*q.x - q.y*q.y + q.z*q.z);

  return result;
}

// Rotates a vector around an axis
RMAPI
GETS(Vector3) Vector3RotateByAxisAngle(GETS(Vector3) v, GETS(Vector3) axis, float angle)
{
  // Using Euler-Rodrigues Formula
  // Ref.: https://en.wikipedia.org/w/index.php?title=Euler%E2%80%93Rodrigues_formula

  GETS(Vector3) result = v;

  // GETS(Vector3)Normalize(axis);
  float length = sqrtf(axis.x*axis.x + axis.y*axis.y + axis.z*axis.z);
  if (length == 0.0f) length = 1.0f;
  float ilength = 1.0f/length;
  axis.x *= ilength;
  axis.y *= ilength;
  axis.z *= ilength;

  angle /= 2.0f;
  float a = sinf(angle);
  float b = axis.x*a;
  float c = axis.y*a;
  float d = axis.z*a;
  a = cosf(angle);
  GETS(Vector3) w = { b, c, d };

  // GETS(Vector3)CrossProduct(w, v)
  GETS(Vector3) wv = { w.y*v.z - w.z*v.y, w.z*v.x - w.x*v.z, w.x*v.y - w.y*v.x };

  // GETS(Vector3)CrossProduct(w, wv)
  GETS(Vector3) wwv = { w.y*wv.z - w.z*wv.y, w.z*wv.x - w.x*wv.z, w.x*wv.y - w.y*wv.x };

  // GETS(Vector3)Scale(wv, 2*a)
  a *= 2;
  wv.x *= a;
  wv.y *= a;
  wv.z *= a;

  // GETS(Vector3)Scale(wwv, 2)
  wwv.x *= 2;
  wwv.y *= 2;
  wwv.z *= 2;

  result.x += wv.x;
  result.y += wv.y;
  result.z += wv.z;

  result.x += wwv.x;
  result.y += wwv.y;
  result.z += wwv.z;

  return result;
}

// Move Vector towards target
RMAPI
GETS(Vector3) Vector3MoveTowards(GETS(Vector3) v, GETS(Vector3) target, float maxDistance)
{
  GETS(Vector3) result = { 0 };

  float dx = target.x - v.x;
  float dy = target.y - v.y;
  float dz = target.z - v.z;
  float value = (dx*dx) + (dy*dy) + (dz*dz);

  if ((value == 0) || ((maxDistance >= 0) && (value <= maxDistance*maxDistance))) return target;

  float dist = sqrtf(value);

  result.x = v.x + dx/dist*maxDistance;
  result.y = v.y + dy/dist*maxDistance;
  result.z = v.z + dz/dist*maxDistance;

  return result;
}

// Calculate linear interpolation between two vectors
RMAPI
GETS(Vector3) Vector3Lerp(GETS(Vector3) v1, GETS(Vector3) v2, float amount)
{
  GETS(Vector3) result = { 0 };

  result.x = v1.x + amount*(v2.x - v1.x);
  result.y = v1.y + amount*(v2.y - v1.y);
  result.z = v1.z + amount*(v2.z - v1.z);

  return result;
}

// Calculate cubic hermite interpolation between two vectors and their tangents
// as described in the GLTF 2.0 specification: https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#interpolation-cubic
RMAPI
GETS(Vector3) Vector3CubicHermite(GETS(Vector3) v1, GETS(Vector3) tangent1, GETS(Vector3) v2, GETS(Vector3) tangent2, float amount)
{
  GETS(Vector3) result = { 0 };

  float amountPow2 = amount * amount;
  float amountPow3 = amount * amount * amount;

  result.x = (2 * amountPow3 - 3 * amountPow2 + 1) * v1.x + (amountPow3 - 2 * amountPow2 + amount) * tangent1.x + (-2 * amountPow3 + 3 * amountPow2) * v2.x + (amountPow3 - amountPow2) * tangent2.x;
  result.y = (2 * amountPow3 - 3 * amountPow2 + 1) * v1.y + (amountPow3 - 2 * amountPow2 + amount) * tangent1.y + (-2 * amountPow3 + 3 * amountPow2) * v2.y + (amountPow3 - amountPow2) * tangent2.y;
  result.z = (2 * amountPow3 - 3 * amountPow2 + 1) * v1.z + (amountPow3 - 2 * amountPow2 + amount) * tangent1.z + (-2 * amountPow3 + 3 * amountPow2) * v2.z + (amountPow3 - amountPow2) * tangent2.z;

  return result;
}

// Calculate reflected vector to normal
RMAPI
GETS(Vector3) Vector3Reflect(GETS(Vector3) v, GETS(Vector3) normal)
{
  GETS(Vector3) result = { 0 };

  // I is the original vector
  // N is the normal of the incident plane
  // R = I - (2*N*(DotProduct[I, N]))

  float dotProduct = (v.x*normal.x + v.y*normal.y + v.z*normal.z);

  result.x = v.x - (2.0f*normal.x)*dotProduct;
  result.y = v.y - (2.0f*normal.y)*dotProduct;
  result.z = v.z - (2.0f*normal.z)*dotProduct;

  return result;
}

// Get min value for each pair of components
RMAPI
GETS(Vector3) Vector3Min(GETS(Vector3) v1, GETS(Vector3) v2)
{
  GETS(Vector3) result = { 0 };

  result.x = fminf(v1.x, v2.x);
  result.y = fminf(v1.y, v2.y);
  result.z = fminf(v1.z, v2.z);

  return result;
}

// Get max value for each pair of components
RMAPI
GETS(Vector3) Vector3Max(GETS(Vector3) v1, GETS(Vector3) v2)
{
  GETS(Vector3) result = { 0 };

  result.x = fmaxf(v1.x, v2.x);
  result.y = fmaxf(v1.y, v2.y);
  result.z = fmaxf(v1.z, v2.z);

  return result;
}

// Compute barycenter coordinates (u, v, w) for point p with respect to triangle (a, b, c)
// NOTE: Assumes P is on the plane of the triangle
RMAPI
GETS(Vector3) Vector3Barycenter(GETS(Vector3) p, GETS(Vector3) a, GETS(Vector3) b, GETS(Vector3) c)
{
  GETS(Vector3) result = { 0 };

  GETS(Vector3) v0 = { b.x - a.x, b.y - a.y, b.z - a.z };   // GETS(Vector3)Subtract(b, a)
  GETS(Vector3) v1 = { c.x - a.x, c.y - a.y, c.z - a.z };   // GETS(Vector3)Subtract(c, a)
  GETS(Vector3) v2 = { p.x - a.x, p.y - a.y, p.z - a.z };   // GETS(Vector3)Subtract(p, a)
  float d00 = (v0.x*v0.x + v0.y*v0.y + v0.z*v0.z);    // GETS(Vector3)DotProduct(v0, v0)
  float d01 = (v0.x*v1.x + v0.y*v1.y + v0.z*v1.z);    // GETS(Vector3)DotProduct(v0, v1)
  float d11 = (v1.x*v1.x + v1.y*v1.y + v1.z*v1.z);    // GETS(Vector3)DotProduct(v1, v1)
  float d20 = (v2.x*v0.x + v2.y*v0.y + v2.z*v0.z);    // GETS(Vector3)DotProduct(v2, v0)
  float d21 = (v2.x*v1.x + v2.y*v1.y + v2.z*v1.z);    // GETS(Vector3)DotProduct(v2, v1)

  float denom = d00*d11 - d01*d01;

  result.y = (d11*d20 - d01*d21)/denom;
  result.z = (d00*d21 - d01*d20)/denom;
  result.x = 1.0f - (result.z + result.y);

  return result;
}

// Projects a GETS(Vector3) from screen space into object space
// NOTE: We are avoiding calling other raymath functions despite available
RMAPI
GETS(Vector3) Vector3Unproject(GETS(Vector3) source, GETS(Matrix) projection, GETS(Matrix) view)
{
  GETS(Vector3) result = { 0 };

  // Calculate unprojected matrix (multiply view matrix by projection matrix) and invert it
  GETS(Matrix) matViewProj = {      // GETS(Matrix)Multiply(view, projection);
    view.m0*projection.m0 + view.m1*projection.m4 + view.m2*projection.m8 + view.m3*projection.m12,
    view.m0*projection.m1 + view.m1*projection.m5 + view.m2*projection.m9 + view.m3*projection.m13,
    view.m0*projection.m2 + view.m1*projection.m6 + view.m2*projection.m10 + view.m3*projection.m14,
    view.m0*projection.m3 + view.m1*projection.m7 + view.m2*projection.m11 + view.m3*projection.m15,
    view.m4*projection.m0 + view.m5*projection.m4 + view.m6*projection.m8 + view.m7*projection.m12,
    view.m4*projection.m1 + view.m5*projection.m5 + view.m6*projection.m9 + view.m7*projection.m13,
    view.m4*projection.m2 + view.m5*projection.m6 + view.m6*projection.m10 + view.m7*projection.m14,
    view.m4*projection.m3 + view.m5*projection.m7 + view.m6*projection.m11 + view.m7*projection.m15,
    view.m8*projection.m0 + view.m9*projection.m4 + view.m10*projection.m8 + view.m11*projection.m12,
    view.m8*projection.m1 + view.m9*projection.m5 + view.m10*projection.m9 + view.m11*projection.m13,
    view.m8*projection.m2 + view.m9*projection.m6 + view.m10*projection.m10 + view.m11*projection.m14,
    view.m8*projection.m3 + view.m9*projection.m7 + view.m10*projection.m11 + view.m11*projection.m15,
    view.m12*projection.m0 + view.m13*projection.m4 + view.m14*projection.m8 + view.m15*projection.m12,
    view.m12*projection.m1 + view.m13*projection.m5 + view.m14*projection.m9 + view.m15*projection.m13,
    view.m12*projection.m2 + view.m13*projection.m6 + view.m14*projection.m10 + view.m15*projection.m14,
    view.m12*projection.m3 + view.m13*projection.m7 + view.m14*projection.m11 + view.m15*projection.m15
  };

  // Calculate inverted matrix -> GETS(Matrix)Invert(matViewProj);
  // Cache the matrix values (speed optimization)
  float a00 = matViewProj.m0, a01 = matViewProj.m1, a02 = matViewProj.m2, a03 = matViewProj.m3;
  float a10 = matViewProj.m4, a11 = matViewProj.m5, a12 = matViewProj.m6, a13 = matViewProj.m7;
  float a20 = matViewProj.m8, a21 = matViewProj.m9, a22 = matViewProj.m10, a23 = matViewProj.m11;
  float a30 = matViewProj.m12, a31 = matViewProj.m13, a32 = matViewProj.m14, a33 = matViewProj.m15;

  float b00 = a00*a11 - a01*a10;
  float b01 = a00*a12 - a02*a10;
  float b02 = a00*a13 - a03*a10;
  float b03 = a01*a12 - a02*a11;
  float b04 = a01*a13 - a03*a11;
  float b05 = a02*a13 - a03*a12;
  float b06 = a20*a31 - a21*a30;
  float b07 = a20*a32 - a22*a30;
  float b08 = a20*a33 - a23*a30;
  float b09 = a21*a32 - a22*a31;
  float b10 = a21*a33 - a23*a31;
  float b11 = a22*a33 - a23*a32;

  // Calculate the invert determinant (inlined to avoid double-caching)
  float invDet = 1.0f/(b00*b11 - b01*b10 + b02*b09 + b03*b08 - b04*b07 + b05*b06);

  GETS(Matrix) matViewProjInv = {
    (a11*b11 - a12*b10 + a13*b09)*invDet,
    (-a01*b11 + a02*b10 - a03*b09)*invDet,
    (a31*b05 - a32*b04 + a33*b03)*invDet,
    (-a21*b05 + a22*b04 - a23*b03)*invDet,
    (-a10*b11 + a12*b08 - a13*b07)*invDet,
    (a00*b11 - a02*b08 + a03*b07)*invDet,
    (-a30*b05 + a32*b02 - a33*b01)*invDet,
    (a20*b05 - a22*b02 + a23*b01)*invDet,
    (a10*b10 - a11*b08 + a13*b06)*invDet,
    (-a00*b10 + a01*b08 - a03*b06)*invDet,
    (a30*b04 - a31*b02 + a33*b00)*invDet,
    (-a20*b04 + a21*b02 - a23*b00)*invDet,
    (-a10*b09 + a11*b07 - a12*b06)*invDet,
    (a00*b09 - a01*b07 + a02*b06)*invDet,
    (-a30*b03 + a31*b01 - a32*b00)*invDet,
    (a20*b03 - a21*b01 + a22*b00)*invDet
  };

  // Create quaternion from source point
  GETS(Quaternion) quat = { source.x, source.y, source.z, 1.0f };

  // Multiply quat point by unprojecte matrix
  GETS(Quaternion) qtransformed = {     // GETS(Quaternion)Transform(quat, matViewProjInv)
    matViewProjInv.m0*quat.x + matViewProjInv.m4*quat.y + matViewProjInv.m8*quat.z + matViewProjInv.m12*quat.w,
    matViewProjInv.m1*quat.x + matViewProjInv.m5*quat.y + matViewProjInv.m9*quat.z + matViewProjInv.m13*quat.w,
    matViewProjInv.m2*quat.x + matViewProjInv.m6*quat.y + matViewProjInv.m10*quat.z + matViewProjInv.m14*quat.w,
    matViewProjInv.m3*quat.x + matViewProjInv.m7*quat.y + matViewProjInv.m11*quat.z + matViewProjInv.m15*quat.w
  };

  // Normalized world points in vectors
  result.x = qtransformed.x/qtransformed.w;
  result.y = qtransformed.y/qtransformed.w;
  result.z = qtransformed.z/qtransformed.w;

  return result;
}

// Get GETS(Vector3) as float array
RMAPI float3
Vector3ToFloatV(GETS(Vector3) v)
{
  float3 buffer = { 0 };

  buffer.v[0] = v.x;
  buffer.v[1] = v.y;
  buffer.v[2] = v.z;

  return buffer;
}

// Invert the given vector
RMAPI
GETS(Vector3) Vector3Invert(GETS(Vector3) v)
{
  GETS(Vector3) result = { 1.0f/v.x, 1.0f/v.y, 1.0f/v.z };

  return result;
}

// Clamp the components of the vector between
// min and max values specified by the given vectors
RMAPI
GETS(Vector3) Vector3Clamp(GETS(Vector3) v, GETS(Vector3) min, GETS(Vector3) max)
{
  GETS(Vector3) result = { 0 };

  result.x = fminf(max.x, fmaxf(min.x, v.x));
  result.y = fminf(max.y, fmaxf(min.y, v.y));
  result.z = fminf(max.z, fmaxf(min.z, v.z));

  return result;
}

// Clamp the magnitude of the vector between two values
RMAPI
GETS(Vector3) Vector3ClampValue(GETS(Vector3) v, float min, float max)
{
  GETS(Vector3) result = v;

  float length = (v.x*v.x) + (v.y*v.y) + (v.z*v.z);
  if (length > 0.0f) {
    length = sqrtf(length);

    float scale = 1;    // By default, 1 as the neutral element.
    if (length < min) {
      scale = min/length;
    } else if (length > max) {
      scale = max/length;
    }

    result.x = v.x*scale;
    result.y = v.y*scale;
    result.z = v.z*scale;
  }

  return result;
}

// Check whether two given vectors are almost equal
RMAPI int
Vector3Equals(GETS(Vector3) p, GETS(Vector3) q)
{
#if !defined(EPSILON)
#define EPSILON 0.000001f
#endif

  int result = ((fabsf(p.x - q.x)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.x), fabsf(q.x))))) &&
               ((fabsf(p.y - q.y)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.y), fabsf(q.y))))) &&
               ((fabsf(p.z - q.z)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.z), fabsf(q.z)))));

  return result;
}

// Compute the direction of a refracted ray
// v: normalized direction of the incoming ray
// n: normalized normal vector of the interface of two optical media
// r: ratio of the refractive index of the medium from where the ray comes
//    to the refractive index of the medium on the other side of the surface
RMAPI
GETS(Vector3) Vector3Refract(GETS(Vector3) v, GETS(Vector3) n, float r)
{
  GETS(Vector3) result = { 0 };

  float dot = v.x*n.x + v.y*n.y + v.z*n.z;
  float d = 1.0f - r*r*(1.0f - dot*dot);

  if (d >= 0.0f) {
    d = sqrtf(d);
    v.x = r*v.x - (r*dot + d)*n.x;
    v.y = r*v.y - (r*dot + d)*n.y;
    v.z = r*v.z - (r*dot + d)*n.z;

    result = v;
  }

  return result;
}


//----------------------------------------------------------------------------------
// Module Functions Definition - Vector4 math
//----------------------------------------------------------------------------------

RMAPI
GETS(Vector4) Vector4Zero(void)
{
  GETS(Vector4) result = { 0.0f, 0.0f, 0.0f, 0.0f };
  return result;
}

RMAPI
GETS(Vector4) Vector4One(void)
{
  GETS(Vector4) result = { 1.0f, 1.0f, 1.0f, 1.0f };
  return result;
}

RMAPI
GETS(Vector4) Vector4Add(GETS(Vector4) v1, GETS(Vector4) v2)
{
  GETS(Vector4) result = {
    v1.x + v2.x,
    v1.y + v2.y,
    v1.z + v2.z,
    v1.w + v2.w
  };
  return result;
}

RMAPI
GETS(Vector4) Vector4AddValue(GETS(Vector4) v, float add)
{
  GETS(Vector4) result = {
    v.x + add,
    v.y + add,
    v.z + add,
    v.w + add
  };
  return result;
}

RMAPI
GETS(Vector4) Vector4Subtract(GETS(Vector4) v1, GETS(Vector4) v2)
{
  GETS(Vector4) result = {
    v1.x - v2.x,
    v1.y - v2.y,
    v1.z - v2.z,
    v1.w - v2.w
  };
  return result;
}

RMAPI
GETS(Vector4) Vector4SubtractValue(GETS(Vector4) v, float add)
{
  GETS(Vector4) result = {
    v.x - add,
    v.y - add,
    v.z - add,
    v.w - add
  };
  return result;
}

RMAPI float
Vector4Length(GETS(Vector4) v)
{
  float result = sqrtf((v.x*v.x) + (v.y*v.y) + (v.z*v.z) + (v.w*v.w));
  return result;
}

RMAPI float
Vector4LengthSqr(GETS(Vector4) v)
{
  float result = (v.x*v.x) + (v.y*v.y) + (v.z*v.z) + (v.w*v.w);
  return result;
}

RMAPI float
Vector4DotProduct(GETS(Vector4) v1, GETS(Vector4) v2)
{
  float result = (v1.x*v2.x + v1.y*v2.y + v1.z*v2.z + v1.w*v2.w);
  return result;
}

// Calculate distance between two vectors
RMAPI float
Vector4Distance(GETS(Vector4) v1, GETS(Vector4) v2)
{
  float result = sqrtf(
                   (v1.x - v2.x)*(v1.x - v2.x) + (v1.y - v2.y)*(v1.y - v2.y) +
                   (v1.z - v2.z)*(v1.z - v2.z) + (v1.w - v2.w)*(v1.w - v2.w));
  return result;
}

// Calculate square distance between two vectors
RMAPI float
Vector4DistanceSqr(GETS(Vector4) v1, GETS(Vector4) v2)
{
  float result =
    (v1.x - v2.x)*(v1.x - v2.x) + (v1.y - v2.y)*(v1.y - v2.y) +
    (v1.z - v2.z)*(v1.z - v2.z) + (v1.w - v2.w)*(v1.w - v2.w);

  return result;
}

RMAPI
GETS(Vector4) Vector4Scale(GETS(Vector4) v, float scale)
{
  GETS(Vector4) result = { v.x*scale, v.y*scale, v.z*scale, v.w*scale };
  return result;
}

// Multiply vector by vector
RMAPI
GETS(Vector4) Vector4Multiply(GETS(Vector4) v1, GETS(Vector4) v2)
{
  GETS(Vector4) result = { v1.x*v2.x, v1.y*v2.y, v1.z*v2.z, v1.w*v2.w };
  return result;
}

// Negate vector
RMAPI
GETS(Vector4) Vector4Negate(GETS(Vector4) v)
{
  GETS(Vector4) result = { -v.x, -v.y, -v.z, -v.w };
  return result;
}

// Divide vector by vector
RMAPI
GETS(Vector4) Vector4Divide(GETS(Vector4) v1, GETS(Vector4) v2)
{
  GETS(Vector4) result = { v1.x/v2.x, v1.y/v2.y, v1.z/v2.z, v1.w/v2.w };
  return result;
}

// Normalize provided vector
RMAPI
GETS(Vector4) Vector4Normalize(GETS(Vector4) v)
{
  GETS(Vector4) result = { 0 };
  float length = sqrtf((v.x*v.x) + (v.y*v.y) + (v.z*v.z) + (v.w*v.w));

  if (length > 0) {
    float ilength = 1.0f/length;
    result.x = v.x*ilength;
    result.y = v.y*ilength;
    result.z = v.z*ilength;
    result.w = v.w*ilength;
  }

  return result;
}

// Get min value for each pair of components
RMAPI
GETS(Vector4) Vector4Min(GETS(Vector4) v1, GETS(Vector4) v2)
{
  GETS(Vector4) result = { 0 };

  result.x = fminf(v1.x, v2.x);
  result.y = fminf(v1.y, v2.y);
  result.z = fminf(v1.z, v2.z);
  result.w = fminf(v1.w, v2.w);

  return result;
}

// Get max value for each pair of components
RMAPI
GETS(Vector4) Vector4Max(GETS(Vector4) v1, GETS(Vector4) v2)
{
  GETS(Vector4) result = { 0 };

  result.x = fmaxf(v1.x, v2.x);
  result.y = fmaxf(v1.y, v2.y);
  result.z = fmaxf(v1.z, v2.z);
  result.w = fmaxf(v1.w, v2.w);

  return result;
}

// Calculate linear interpolation between two vectors
RMAPI
GETS(Vector4) Vector4Lerp(GETS(Vector4) v1, GETS(Vector4) v2, float amount)
{
  GETS(Vector4) result = { 0 };

  result.x = v1.x + amount*(v2.x - v1.x);
  result.y = v1.y + amount*(v2.y - v1.y);
  result.z = v1.z + amount*(v2.z - v1.z);
  result.w = v1.w + amount*(v2.w - v1.w);

  return result;
}

// Move Vector towards target
RMAPI
GETS(Vector4) Vector4MoveTowards(GETS(Vector4) v, GETS(Vector4) target, float maxDistance)
{
  GETS(Vector4) result = { 0 };

  float dx = target.x - v.x;
  float dy = target.y - v.y;
  float dz = target.z - v.z;
  float dw = target.w - v.w;
  float value = (dx*dx) + (dy*dy) + (dz*dz) + (dw*dw);

  if ((value == 0) || ((maxDistance >= 0) && (value <= maxDistance*maxDistance))) return target;

  float dist = sqrtf(value);

  result.x = v.x + dx/dist*maxDistance;
  result.y = v.y + dy/dist*maxDistance;
  result.z = v.z + dz/dist*maxDistance;
  result.w = v.w + dw/dist*maxDistance;

  return result;
}

// Invert the given vector
RMAPI
GETS(Vector4) Vector4Invert(GETS(Vector4) v)
{
  GETS(Vector4) result = { 1.0f/v.x, 1.0f/v.y, 1.0f/v.z, 1.0f/v.w };
  return result;
}

// Check whether two given vectors are almost equal
RMAPI int
Vector4Equals(GETS(Vector4) p, GETS(Vector4) q)
{
#if !defined(EPSILON)
#define EPSILON 0.000001f
#endif

  int result = ((fabsf(p.x - q.x)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.x), fabsf(q.x))))) &&
               ((fabsf(p.y - q.y)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.y), fabsf(q.y))))) &&
               ((fabsf(p.z - q.z)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.z), fabsf(q.z))))) &&
               ((fabsf(p.w - q.w)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.w), fabsf(q.w)))));
  return result;
}


//----------------------------------------------------------------------------------
// Module Functions Definition - GETS(Matrix) math
//----------------------------------------------------------------------------------

// Compute matrix determinant
RMAPI float
MatrixDeterminant(GETS(Matrix) mat)
{
  float result = 0.0f;

  // Cache the matrix values (speed optimization)
  float a00 = mat.m0, a01 = mat.m1, a02 = mat.m2, a03 = mat.m3;
  float a10 = mat.m4, a11 = mat.m5, a12 = mat.m6, a13 = mat.m7;
  float a20 = mat.m8, a21 = mat.m9, a22 = mat.m10, a23 = mat.m11;
  float a30 = mat.m12, a31 = mat.m13, a32 = mat.m14, a33 = mat.m15;

  result = a30*a21*a12*a03 - a20*a31*a12*a03 - a30*a11*a22*a03 + a10*a31*a22*a03 +
           a20*a11*a32*a03 - a10*a21*a32*a03 - a30*a21*a02*a13 + a20*a31*a02*a13 +
           a30*a01*a22*a13 - a00*a31*a22*a13 - a20*a01*a32*a13 + a00*a21*a32*a13 +
           a30*a11*a02*a23 - a10*a31*a02*a23 - a30*a01*a12*a23 + a00*a31*a12*a23 +
           a10*a01*a32*a23 - a00*a11*a32*a23 - a20*a11*a02*a33 + a10*a21*a02*a33 +
           a20*a01*a12*a33 - a00*a21*a12*a33 - a10*a01*a22*a33 + a00*a11*a22*a33;

  return result;
}

// Get the trace of the matrix (sum of the values along the diagonal)
RMAPI float
MatrixTrace(GETS(Matrix) mat)
{
  float result = (mat.m0 + mat.m5 + mat.m10 + mat.m15);

  return result;
}

// Transposes provided matrix
RMAPI
GETS(Matrix) MatrixTranspose(GETS(Matrix) mat)
{
  GETS(Matrix) result = { 0 };

  result.m0 = mat.m0;
  result.m1 = mat.m4;
  result.m2 = mat.m8;
  result.m3 = mat.m12;
  result.m4 = mat.m1;
  result.m5 = mat.m5;
  result.m6 = mat.m9;
  result.m7 = mat.m13;
  result.m8 = mat.m2;
  result.m9 = mat.m6;
  result.m10 = mat.m10;
  result.m11 = mat.m14;
  result.m12 = mat.m3;
  result.m13 = mat.m7;
  result.m14 = mat.m11;
  result.m15 = mat.m15;

  return result;
}

// Invert provided matrix
RMAPI
GETS(Matrix) MatrixInvert(GETS(Matrix) mat)
{
  GETS(Matrix) result = { 0 };

  // Cache the matrix values (speed optimization)
  float a00 = mat.m0, a01 = mat.m1, a02 = mat.m2, a03 = mat.m3;
  float a10 = mat.m4, a11 = mat.m5, a12 = mat.m6, a13 = mat.m7;
  float a20 = mat.m8, a21 = mat.m9, a22 = mat.m10, a23 = mat.m11;
  float a30 = mat.m12, a31 = mat.m13, a32 = mat.m14, a33 = mat.m15;

  float b00 = a00*a11 - a01*a10;
  float b01 = a00*a12 - a02*a10;
  float b02 = a00*a13 - a03*a10;
  float b03 = a01*a12 - a02*a11;
  float b04 = a01*a13 - a03*a11;
  float b05 = a02*a13 - a03*a12;
  float b06 = a20*a31 - a21*a30;
  float b07 = a20*a32 - a22*a30;
  float b08 = a20*a33 - a23*a30;
  float b09 = a21*a32 - a22*a31;
  float b10 = a21*a33 - a23*a31;
  float b11 = a22*a33 - a23*a32;

  // Calculate the invert determinant (inlined to avoid double-caching)
  float invDet = 1.0f/(b00*b11 - b01*b10 + b02*b09 + b03*b08 - b04*b07 + b05*b06);

  result.m0 = (a11*b11 - a12*b10 + a13*b09)*invDet;
  result.m1 = (-a01*b11 + a02*b10 - a03*b09)*invDet;
  result.m2 = (a31*b05 - a32*b04 + a33*b03)*invDet;
  result.m3 = (-a21*b05 + a22*b04 - a23*b03)*invDet;
  result.m4 = (-a10*b11 + a12*b08 - a13*b07)*invDet;
  result.m5 = (a00*b11 - a02*b08 + a03*b07)*invDet;
  result.m6 = (-a30*b05 + a32*b02 - a33*b01)*invDet;
  result.m7 = (a20*b05 - a22*b02 + a23*b01)*invDet;
  result.m8 = (a10*b10 - a11*b08 + a13*b06)*invDet;
  result.m9 = (-a00*b10 + a01*b08 - a03*b06)*invDet;
  result.m10 = (a30*b04 - a31*b02 + a33*b00)*invDet;
  result.m11 = (-a20*b04 + a21*b02 - a23*b00)*invDet;
  result.m12 = (-a10*b09 + a11*b07 - a12*b06)*invDet;
  result.m13 = (a00*b09 - a01*b07 + a02*b06)*invDet;
  result.m14 = (-a30*b03 + a31*b01 - a32*b00)*invDet;
  result.m15 = (a20*b03 - a21*b01 + a22*b00)*invDet;

  return result;
}

// Get identity matrix
RMAPI
GETS(Matrix) MatrixIdentity(void)
{
  GETS(Matrix) result = { 1.0f, 0.0f, 0.0f, 0.0f,
                          0.0f, 1.0f, 0.0f, 0.0f,
                          0.0f, 0.0f, 1.0f, 0.0f,
                          0.0f, 0.0f, 0.0f, 1.0f
                        };

  return result;
}

// Add two matrices
RMAPI
GETS(Matrix) MatrixAdd(GETS(Matrix) left, GETS(Matrix) right)
{
  GETS(Matrix) result = { 0 };

  result.m0 = left.m0 + right.m0;
  result.m1 = left.m1 + right.m1;
  result.m2 = left.m2 + right.m2;
  result.m3 = left.m3 + right.m3;
  result.m4 = left.m4 + right.m4;
  result.m5 = left.m5 + right.m5;
  result.m6 = left.m6 + right.m6;
  result.m7 = left.m7 + right.m7;
  result.m8 = left.m8 + right.m8;
  result.m9 = left.m9 + right.m9;
  result.m10 = left.m10 + right.m10;
  result.m11 = left.m11 + right.m11;
  result.m12 = left.m12 + right.m12;
  result.m13 = left.m13 + right.m13;
  result.m14 = left.m14 + right.m14;
  result.m15 = left.m15 + right.m15;

  return result;
}

// Subtract two matrices (left - right)
RMAPI
GETS(Matrix) MatrixSubtract(GETS(Matrix) left, GETS(Matrix) right)
{
  GETS(Matrix) result = { 0 };

  result.m0 = left.m0 - right.m0;
  result.m1 = left.m1 - right.m1;
  result.m2 = left.m2 - right.m2;
  result.m3 = left.m3 - right.m3;
  result.m4 = left.m4 - right.m4;
  result.m5 = left.m5 - right.m5;
  result.m6 = left.m6 - right.m6;
  result.m7 = left.m7 - right.m7;
  result.m8 = left.m8 - right.m8;
  result.m9 = left.m9 - right.m9;
  result.m10 = left.m10 - right.m10;
  result.m11 = left.m11 - right.m11;
  result.m12 = left.m12 - right.m12;
  result.m13 = left.m13 - right.m13;
  result.m14 = left.m14 - right.m14;
  result.m15 = left.m15 - right.m15;

  return result;
}

// Get two matrix multiplication
// NOTE: When multiplying matrices... the order matters!
RMAPI
GETS(Matrix) MatrixMultiply(GETS(Matrix) left, GETS(Matrix) right)
{
  GETS(Matrix) result = { 0 };

  result.m0 = left.m0*right.m0 + left.m1*right.m4 + left.m2*right.m8 + left.m3*right.m12;
  result.m1 = left.m0*right.m1 + left.m1*right.m5 + left.m2*right.m9 + left.m3*right.m13;
  result.m2 = left.m0*right.m2 + left.m1*right.m6 + left.m2*right.m10 + left.m3*right.m14;
  result.m3 = left.m0*right.m3 + left.m1*right.m7 + left.m2*right.m11 + left.m3*right.m15;
  result.m4 = left.m4*right.m0 + left.m5*right.m4 + left.m6*right.m8 + left.m7*right.m12;
  result.m5 = left.m4*right.m1 + left.m5*right.m5 + left.m6*right.m9 + left.m7*right.m13;
  result.m6 = left.m4*right.m2 + left.m5*right.m6 + left.m6*right.m10 + left.m7*right.m14;
  result.m7 = left.m4*right.m3 + left.m5*right.m7 + left.m6*right.m11 + left.m7*right.m15;
  result.m8 = left.m8*right.m0 + left.m9*right.m4 + left.m10*right.m8 + left.m11*right.m12;
  result.m9 = left.m8*right.m1 + left.m9*right.m5 + left.m10*right.m9 + left.m11*right.m13;
  result.m10 = left.m8*right.m2 + left.m9*right.m6 + left.m10*right.m10 + left.m11*right.m14;
  result.m11 = left.m8*right.m3 + left.m9*right.m7 + left.m10*right.m11 + left.m11*right.m15;
  result.m12 = left.m12*right.m0 + left.m13*right.m4 + left.m14*right.m8 + left.m15*right.m12;
  result.m13 = left.m12*right.m1 + left.m13*right.m5 + left.m14*right.m9 + left.m15*right.m13;
  result.m14 = left.m12*right.m2 + left.m13*right.m6 + left.m14*right.m10 + left.m15*right.m14;
  result.m15 = left.m12*right.m3 + left.m13*right.m7 + left.m14*right.m11 + left.m15*right.m15;

  return result;
}

// Get translation matrix
RMAPI
GETS(Matrix) MatrixTranslate(float x, float y, float z)
{
  GETS(Matrix) result = { 1.0f, 0.0f, 0.0f, x,
                          0.0f, 1.0f, 0.0f, y,
                          0.0f, 0.0f, 1.0f, z,
                          0.0f, 0.0f, 0.0f, 1.0f
                        };

  return result;
}

// Create rotation matrix from axis and angle
// NOTE: Angle should be provided in radians
RMAPI
GETS(Matrix) MatrixRotate(GETS(Vector3) axis, float angle)
{
  GETS(Matrix) result = { 0 };

  float x = axis.x, y = axis.y, z = axis.z;

  float lengthSquared = x*x + y*y + z*z;

  if ((lengthSquared != 1.0f) && (lengthSquared != 0.0f)) {
    float ilength = 1.0f/sqrtf(lengthSquared);
    x *= ilength;
    y *= ilength;
    z *= ilength;
  }

  float sinres = sinf(angle);
  float cosres = cosf(angle);
  float t = 1.0f - cosres;

  result.m0 = x*x*t + cosres;
  result.m1 = y*x*t + z*sinres;
  result.m2 = z*x*t - y*sinres;
  result.m3 = 0.0f;

  result.m4 = x*y*t - z*sinres;
  result.m5 = y*y*t + cosres;
  result.m6 = z*y*t + x*sinres;
  result.m7 = 0.0f;

  result.m8 = x*z*t + y*sinres;
  result.m9 = y*z*t - x*sinres;
  result.m10 = z*z*t + cosres;
  result.m11 = 0.0f;

  result.m12 = 0.0f;
  result.m13 = 0.0f;
  result.m14 = 0.0f;
  result.m15 = 1.0f;

  return result;
}

// Get x-rotation matrix
// NOTE: Angle must be provided in radians
RMAPI
GETS(Matrix) MatrixRotateX(float angle)
{
  GETS(Matrix) result = { 1.0f, 0.0f, 0.0f, 0.0f,
                          0.0f, 1.0f, 0.0f, 0.0f,
                          0.0f, 0.0f, 1.0f, 0.0f,
                          0.0f, 0.0f, 0.0f, 1.0f
                        }; // GETS(Matrix)Identity()

  float cosres = cosf(angle);
  float sinres = sinf(angle);

  result.m5 = cosres;
  result.m6 = sinres;
  result.m9 = -sinres;
  result.m10 = cosres;

  return result;
}

// Get y-rotation matrix
// NOTE: Angle must be provided in radians
RMAPI
GETS(Matrix) MatrixRotateY(float angle)
{
  GETS(Matrix) result = { 1.0f, 0.0f, 0.0f, 0.0f,
                          0.0f, 1.0f, 0.0f, 0.0f,
                          0.0f, 0.0f, 1.0f, 0.0f,
                          0.0f, 0.0f, 0.0f, 1.0f
                        }; // GETS(Matrix)Identity()

  float cosres = cosf(angle);
  float sinres = sinf(angle);

  result.m0 = cosres;
  result.m2 = -sinres;
  result.m8 = sinres;
  result.m10 = cosres;

  return result;
}

// Get z-rotation matrix
// NOTE: Angle must be provided in radians
RMAPI
GETS(Matrix) MatrixRotateZ(float angle)
{
  GETS(Matrix) result = { 1.0f, 0.0f, 0.0f, 0.0f,
                          0.0f, 1.0f, 0.0f, 0.0f,
                          0.0f, 0.0f, 1.0f, 0.0f,
                          0.0f, 0.0f, 0.0f, 1.0f
                        }; // GETS(Matrix)Identity()

  float cosres = cosf(angle);
  float sinres = sinf(angle);

  result.m0 = cosres;
  result.m1 = sinres;
  result.m4 = -sinres;
  result.m5 = cosres;

  return result;
}


// Get xyz-rotation matrix
// NOTE: Angle must be provided in radians
RMAPI
GETS(Matrix) MatrixRotateXYZ(GETS(Vector3) angle)
{
  GETS(Matrix) result = { 1.0f, 0.0f, 0.0f, 0.0f,
                          0.0f, 1.0f, 0.0f, 0.0f,
                          0.0f, 0.0f, 1.0f, 0.0f,
                          0.0f, 0.0f, 0.0f, 1.0f
                        }; // GETS(Matrix)Identity()

  float cosz = cosf(-angle.z);
  float sinz = sinf(-angle.z);
  float cosy = cosf(-angle.y);
  float siny = sinf(-angle.y);
  float cosx = cosf(-angle.x);
  float sinx = sinf(-angle.x);

  result.m0 = cosz*cosy;
  result.m1 = (cosz*siny*sinx) - (sinz*cosx);
  result.m2 = (cosz*siny*cosx) + (sinz*sinx);

  result.m4 = sinz*cosy;
  result.m5 = (sinz*siny*sinx) + (cosz*cosx);
  result.m6 = (sinz*siny*cosx) - (cosz*sinx);

  result.m8 = -siny;
  result.m9 = cosy*sinx;
  result.m10= cosy*cosx;

  return result;
}

// Get zyx-rotation matrix
// NOTE: Angle must be provided in radians
RMAPI
GETS(Matrix) MatrixRotateZYX(GETS(Vector3) angle)
{
  GETS(Matrix) result = { 0 };

  float cz = cosf(angle.z);
  float sz = sinf(angle.z);
  float cy = cosf(angle.y);
  float sy = sinf(angle.y);
  float cx = cosf(angle.x);
  float sx = sinf(angle.x);

  result.m0 = cz*cy;
  result.m4 = cz*sy*sx - cx*sz;
  result.m8 = sz*sx + cz*cx*sy;
  result.m12 = 0;

  result.m1 = cy*sz;
  result.m5 = cz*cx + sz*sy*sx;
  result.m9 = cx*sz*sy - cz*sx;
  result.m13 = 0;

  result.m2 = -sy;
  result.m6 = cy*sx;
  result.m10 = cy*cx;
  result.m14 = 0;

  result.m3 = 0;
  result.m7 = 0;
  result.m11 = 0;
  result.m15 = 1;

  return result;
}

// Get scaling matrix
RMAPI
GETS(Matrix) MatrixScale(float x, float y, float z)
{
  GETS(Matrix) result = { x, 0.0f, 0.0f, 0.0f,
                          0.0f, y, 0.0f, 0.0f,
                          0.0f, 0.0f, z, 0.0f,
                          0.0f, 0.0f, 0.0f, 1.0f
                        };

  return result;
}

// Get perspective projection matrix
RMAPI
GETS(Matrix) MatrixFrustum(double left, double right, double bottom, double top, double nearPlane, double farPlane)
{
  GETS(Matrix) result = { 0 };

  float rl = (float)(right - left);
  float tb = (float)(top - bottom);
  float fn = (float)(farPlane - nearPlane);

  result.m0 = ((float)nearPlane*2.0f)/rl;
  result.m1 = 0.0f;
  result.m2 = 0.0f;
  result.m3 = 0.0f;

  result.m4 = 0.0f;
  result.m5 = ((float)nearPlane*2.0f)/tb;
  result.m6 = 0.0f;
  result.m7 = 0.0f;

  result.m8 = ((float)right + (float)left)/rl;
  result.m9 = ((float)top + (float)bottom)/tb;
  result.m10 = -((float)farPlane + (float)nearPlane)/fn;
  result.m11 = -1.0f;

  result.m12 = 0.0f;
  result.m13 = 0.0f;
  result.m14 = -((float)farPlane*(float)nearPlane*2.0f)/fn;
  result.m15 = 0.0f;

  return result;
}

// Get perspective projection matrix
// NOTE: Fovy angle must be provided in radians
RMAPI
GETS(Matrix) MatrixPerspective(double fovY, double aspect, double nearPlane, double farPlane)
{
  GETS(Matrix) result = { 0 };

  double top = nearPlane*tan(fovY*0.5);
  double bottom = -top;
  double right = top*aspect;
  double left = -right;

  // GETS(Matrix)Frustum(-right, right, -top, top, near, far);
  float rl = (float)(right - left);
  float tb = (float)(top - bottom);
  float fn = (float)(farPlane - nearPlane);

  result.m0 = ((float)nearPlane*2.0f)/rl;
  result.m5 = ((float)nearPlane*2.0f)/tb;
  result.m8 = ((float)right + (float)left)/rl;
  result.m9 = ((float)top + (float)bottom)/tb;
  result.m10 = -((float)farPlane + (float)nearPlane)/fn;
  result.m11 = -1.0f;
  result.m14 = -((float)farPlane*(float)nearPlane*2.0f)/fn;

  return result;
}

// Get orthographic projection matrix
RMAPI
GETS(Matrix) MatrixOrtho(double left, double right, double bottom, double top, double nearPlane, double farPlane)
{
  GETS(Matrix) result = { 0 };

  float rl = (float)(right - left);
  float tb = (float)(top - bottom);
  float fn = (float)(farPlane - nearPlane);

  result.m0 = 2.0f/rl;
  result.m1 = 0.0f;
  result.m2 = 0.0f;
  result.m3 = 0.0f;
  result.m4 = 0.0f;
  result.m5 = 2.0f/tb;
  result.m6 = 0.0f;
  result.m7 = 0.0f;
  result.m8 = 0.0f;
  result.m9 = 0.0f;
  result.m10 = -2.0f/fn;
  result.m11 = 0.0f;
  result.m12 = -((float)left + (float)right)/rl;
  result.m13 = -((float)top + (float)bottom)/tb;
  result.m14 = -((float)farPlane + (float)nearPlane)/fn;
  result.m15 = 1.0f;

  return result;
}

// Get camera look-at matrix (view matrix)
RMAPI
GETS(Matrix) MatrixLookAt(GETS(Vector3) eye, GETS(Vector3) target, GETS(Vector3) up)
{
  GETS(Matrix) result = { 0 };

  float length = 0.0f;
  float ilength = 0.0f;

  // GETS(Vector3)Subtract(eye, target)
  GETS(Vector3) vz = { eye.x - target.x, eye.y - target.y, eye.z - target.z };

  // GETS(Vector3)Normalize(vz)
  GETS(Vector3) v = vz;
  length = sqrtf(v.x*v.x + v.y*v.y + v.z*v.z);
  if (length == 0.0f) length = 1.0f;
  ilength = 1.0f/length;
  vz.x *= ilength;
  vz.y *= ilength;
  vz.z *= ilength;

  // GETS(Vector3)CrossProduct(up, vz)
  GETS(Vector3) vx = { up.y*vz.z - up.z*vz.y, up.z*vz.x - up.x*vz.z, up.x*vz.y - up.y*vz.x };

  // GETS(Vector3)Normalize(x)
  v = vx;
  length = sqrtf(v.x*v.x + v.y*v.y + v.z*v.z);
  if (length == 0.0f) length = 1.0f;
  ilength = 1.0f/length;
  vx.x *= ilength;
  vx.y *= ilength;
  vx.z *= ilength;

  // GETS(Vector3)CrossProduct(vz, vx)
  GETS(Vector3) vy = { vz.y*vx.z - vz.z*vx.y, vz.z*vx.x - vz.x*vx.z, vz.x*vx.y - vz.y*vx.x };

  result.m0 = vx.x;
  result.m1 = vy.x;
  result.m2 = vz.x;
  result.m3 = 0.0f;
  result.m4 = vx.y;
  result.m5 = vy.y;
  result.m6 = vz.y;
  result.m7 = 0.0f;
  result.m8 = vx.z;
  result.m9 = vy.z;
  result.m10 = vz.z;
  result.m11 = 0.0f;
  result.m12 = -(vx.x*eye.x + vx.y*eye.y + vx.z*eye.z);   // GETS(Vector3)DotProduct(vx, eye)
  result.m13 = -(vy.x*eye.x + vy.y*eye.y + vy.z*eye.z);   // GETS(Vector3)DotProduct(vy, eye)
  result.m14 = -(vz.x*eye.x + vz.y*eye.y + vz.z*eye.z);   // GETS(Vector3)DotProduct(vz, eye)
  result.m15 = 1.0f;

  return result;
}

// Get float array of matrix data
RMAPI float16
MatrixToFloatV(GETS(Matrix) mat)
{
  float16 result = { 0 };

  result.v[0] = mat.m0;
  result.v[1] = mat.m1;
  result.v[2] = mat.m2;
  result.v[3] = mat.m3;
  result.v[4] = mat.m4;
  result.v[5] = mat.m5;
  result.v[6] = mat.m6;
  result.v[7] = mat.m7;
  result.v[8] = mat.m8;
  result.v[9] = mat.m9;
  result.v[10] = mat.m10;
  result.v[11] = mat.m11;
  result.v[12] = mat.m12;
  result.v[13] = mat.m13;
  result.v[14] = mat.m14;
  result.v[15] = mat.m15;

  return result;
}

static float *mfbuff = NULL;

RMAPI float*
MatrixToFloat(GETS(Matrix) mat)
{
  float16 r = MatrixToFloatV(mat);
  if (mfbuff == NULL)
    mfbuff = malloc(sizeof(float) * 16);

  memcpy(mfbuff, r.v, 16*sizeof(float));
  return mfbuff;
}


//----------------------------------------------------------------------------------
// Module Functions Definition - GETS(Quaternion) math
//----------------------------------------------------------------------------------

// Add two quaternions
RMAPI
GETS(Quaternion) QuaternionAdd(GETS(Quaternion) q1, GETS(Quaternion) q2)
{
  GETS(Quaternion) result = {q1.x + q2.x, q1.y + q2.y, q1.z + q2.z, q1.w + q2.w};

  return result;
}

// Add quaternion and float value
RMAPI
GETS(Quaternion) QuaternionAddValue(GETS(Quaternion) q, float add)
{
  GETS(Quaternion) result = {q.x + add, q.y + add, q.z + add, q.w + add};

  return result;
}

// Subtract two quaternions
RMAPI
GETS(Quaternion) QuaternionSubtract(GETS(Quaternion) q1, GETS(Quaternion) q2)
{
  GETS(Quaternion) result = {q1.x - q2.x, q1.y - q2.y, q1.z - q2.z, q1.w - q2.w};

  return result;
}

// Subtract quaternion and float value
RMAPI
GETS(Quaternion) QuaternionSubtractValue(GETS(Quaternion) q, float sub)
{
  GETS(Quaternion) result = {q.x - sub, q.y - sub, q.z - sub, q.w - sub};

  return result;
}

// Get identity quaternion
RMAPI
GETS(Quaternion) QuaternionIdentity(void)
{
  GETS(Quaternion) result = { 0.0f, 0.0f, 0.0f, 1.0f };

  return result;
}

// Computes the length of a quaternion
RMAPI float
QuaternionLength(GETS(Quaternion) q)
{
  float result = sqrtf(q.x*q.x + q.y*q.y + q.z*q.z + q.w*q.w);

  return result;
}

// Normalize provided quaternion
RMAPI
GETS(Quaternion) QuaternionNormalize(GETS(Quaternion) q)
{
  GETS(Quaternion) result = { 0 };

  float length = sqrtf(q.x*q.x + q.y*q.y + q.z*q.z + q.w*q.w);
  if (length == 0.0f) length = 1.0f;
  float ilength = 1.0f/length;

  result.x = q.x*ilength;
  result.y = q.y*ilength;
  result.z = q.z*ilength;
  result.w = q.w*ilength;

  return result;
}

// Invert provided quaternion
RMAPI
GETS(Quaternion) QuaternionInvert(GETS(Quaternion) q)
{
  GETS(Quaternion) result = q;

  float lengthSq = q.x*q.x + q.y*q.y + q.z*q.z + q.w*q.w;

  if (lengthSq != 0.0f) {
    float invLength = 1.0f/lengthSq;

    result.x *= -invLength;
    result.y *= -invLength;
    result.z *= -invLength;
    result.w *= invLength;
  }

  return result;
}

// Calculate two quaternion multiplication
RMAPI
GETS(Quaternion) QuaternionMultiply(GETS(Quaternion) q1, GETS(Quaternion) q2)
{
  GETS(Quaternion) result = { 0 };

  float qax = q1.x, qay = q1.y, qaz = q1.z, qaw = q1.w;
  float qbx = q2.x, qby = q2.y, qbz = q2.z, qbw = q2.w;

  result.x = qax*qbw + qaw*qbx + qay*qbz - qaz*qby;
  result.y = qay*qbw + qaw*qby + qaz*qbx - qax*qbz;
  result.z = qaz*qbw + qaw*qbz + qax*qby - qay*qbx;
  result.w = qaw*qbw - qax*qbx - qay*qby - qaz*qbz;

  return result;
}

// Scale quaternion by float value
RMAPI
GETS(Quaternion) QuaternionScale(GETS(Quaternion) q, float mul)
{
  GETS(Quaternion) result = { 0 };

  result.x = q.x*mul;
  result.y = q.y*mul;
  result.z = q.z*mul;
  result.w = q.w*mul;

  return result;
}

// Divide two quaternions
RMAPI
GETS(Quaternion) QuaternionDivide(GETS(Quaternion) q1, GETS(Quaternion) q2)
{
  GETS(Quaternion) result = { q1.x/q2.x, q1.y/q2.y, q1.z/q2.z, q1.w/q2.w };

  return result;
}

// Calculate linear interpolation between two quaternions
RMAPI
GETS(Quaternion) QuaternionLerp(GETS(Quaternion) q1, GETS(Quaternion) q2, float amount)
{
  GETS(Quaternion) result = { 0 };

  result.x = q1.x + amount*(q2.x - q1.x);
  result.y = q1.y + amount*(q2.y - q1.y);
  result.z = q1.z + amount*(q2.z - q1.z);
  result.w = q1.w + amount*(q2.w - q1.w);

  return result;
}

// Calculate slerp-optimized interpolation between two quaternions
RMAPI
GETS(Quaternion) QuaternionNlerp(GETS(Quaternion) q1, GETS(Quaternion) q2, float amount)
{
  GETS(Quaternion) result = { 0 };

  // GETS(Quaternion)Lerp(q1, q2, amount)
  result.x = q1.x + amount*(q2.x - q1.x);
  result.y = q1.y + amount*(q2.y - q1.y);
  result.z = q1.z + amount*(q2.z - q1.z);
  result.w = q1.w + amount*(q2.w - q1.w);

  // GETS(Quaternion)Normalize(q);
  GETS(Quaternion) q = result;
  float length = sqrtf(q.x*q.x + q.y*q.y + q.z*q.z + q.w*q.w);
  if (length == 0.0f) length = 1.0f;
  float ilength = 1.0f/length;

  result.x = q.x*ilength;
  result.y = q.y*ilength;
  result.z = q.z*ilength;
  result.w = q.w*ilength;

  return result;
}

// Calculates spherical linear interpolation between two quaternions
RMAPI
GETS(Quaternion) QuaternionSlerp(GETS(Quaternion) q1, GETS(Quaternion) q2, float amount)
{
  GETS(Quaternion) result = { 0 };

#if !defined(EPSILON)
#define EPSILON 0.000001f
#endif

  float cosHalfTheta = q1.x*q2.x + q1.y*q2.y + q1.z*q2.z + q1.w*q2.w;

  if (cosHalfTheta < 0) {
    q2.x = -q2.x;
    q2.y = -q2.y;
    q2.z = -q2.z;
    q2.w = -q2.w;
    cosHalfTheta = -cosHalfTheta;
  }

  if (fabsf(cosHalfTheta) >= 1.0f) result = q1;
  else if (cosHalfTheta > 0.95f) result = QuaternionNlerp(q1, q2, amount);
  else {
    float halfTheta = acosf(cosHalfTheta);
    float sinHalfTheta = sqrtf(1.0f - cosHalfTheta*cosHalfTheta);

    if (fabsf(sinHalfTheta) < EPSILON) {
      result.x = (q1.x*0.5f + q2.x*0.5f);
      result.y = (q1.y*0.5f + q2.y*0.5f);
      result.z = (q1.z*0.5f + q2.z*0.5f);
      result.w = (q1.w*0.5f + q2.w*0.5f);
    } else {
      float ratioA = sinf((1 - amount)*halfTheta)/sinHalfTheta;
      float ratioB = sinf(amount*halfTheta)/sinHalfTheta;

      result.x = (q1.x*ratioA + q2.x*ratioB);
      result.y = (q1.y*ratioA + q2.y*ratioB);
      result.z = (q1.z*ratioA + q2.z*ratioB);
      result.w = (q1.w*ratioA + q2.w*ratioB);
    }
  }

  return result;
}

// Calculate quaternion cubic spline interpolation using Cubic Hermite Spline algorithm
// as described in the GLTF 2.0 specification: https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#interpolation-cubic
RMAPI
GETS(Quaternion) QuaternionCubicHermiteSpline(GETS(Quaternion) q1, GETS(Quaternion) outTangent1, GETS(Quaternion) q2, GETS(Quaternion) inTangent2, float t)
{
  float t2 = t * t;
  float t3 = t2 * t;
  float h00 = 2 * t3 - 3 * t2 + 1;
  float h10 = t3 - 2 * t2 + t;
  float h01 = -2 * t3 + 3 * t2;
  float h11 = t3 - t2;

  GETS(Quaternion) p0 = QuaternionScale(q1, h00);
  GETS(Quaternion) m0 = QuaternionScale(outTangent1, h10);
  GETS(Quaternion) p1 = QuaternionScale(q2, h01);
  GETS(Quaternion) m1 = QuaternionScale(inTangent2, h11);

  GETS(Quaternion) result = { 0 };

  result = QuaternionAdd(p0, m0);
  result = QuaternionAdd(result, p1);
  result = QuaternionAdd(result, m1);
  result = QuaternionNormalize(result);

  return result;
}

// Calculate quaternion based on the rotation from one vector to another
RMAPI
GETS(Quaternion) QuaternionFromVector3ToVector3(GETS(Vector3) from, GETS(Vector3) to)
{
  GETS(Quaternion) result = { 0 };

  float cos2Theta = (from.x*to.x + from.y*to.y + from.z*to.z);    // GETS(Vector3)DotProduct(from, to)
  GETS(Vector3) cross = { from.y*to.z - from.z*to.y, from.z*to.x - from.x*to.z, from.x*to.y - from.y*to.x }; // GETS(Vector3)CrossProduct(from, to)

  result.x = cross.x;
  result.y = cross.y;
  result.z = cross.z;
  result.w = 1.0f + cos2Theta;

  // GETS(Quaternion)Normalize(q);
  // NOTE: Normalize to essentially nlerp the original and identity to 0.5
  GETS(Quaternion) q = result;
  float length = sqrtf(q.x*q.x + q.y*q.y + q.z*q.z + q.w*q.w);
  if (length == 0.0f) length = 1.0f;
  float ilength = 1.0f/length;

  result.x = q.x*ilength;
  result.y = q.y*ilength;
  result.z = q.z*ilength;
  result.w = q.w*ilength;

  return result;
}

// Get a quaternion for a given rotation matrix
RMAPI
GETS(Quaternion) QuaternionFromMatrix(GETS(Matrix) mat)
{
  GETS(Quaternion) result = { 0 };

  float fourWSquaredMinus1 = mat.m0  + mat.m5 + mat.m10;
  float fourXSquaredMinus1 = mat.m0  - mat.m5 - mat.m10;
  float fourYSquaredMinus1 = mat.m5  - mat.m0 - mat.m10;
  float fourZSquaredMinus1 = mat.m10 - mat.m0 - mat.m5;

  int biggestIndex = 0;
  float fourBiggestSquaredMinus1 = fourWSquaredMinus1;
  if (fourXSquaredMinus1 > fourBiggestSquaredMinus1) {
    fourBiggestSquaredMinus1 = fourXSquaredMinus1;
    biggestIndex = 1;
  }

  if (fourYSquaredMinus1 > fourBiggestSquaredMinus1) {
    fourBiggestSquaredMinus1 = fourYSquaredMinus1;
    biggestIndex = 2;
  }

  if (fourZSquaredMinus1 > fourBiggestSquaredMinus1) {
    fourBiggestSquaredMinus1 = fourZSquaredMinus1;
    biggestIndex = 3;
  }

  float biggestVal = sqrtf(fourBiggestSquaredMinus1 + 1.0f)*0.5f;
  float mult = 0.25f/biggestVal;

  switch (biggestIndex) {
  case 0:
    result.w = biggestVal;
    result.x = (mat.m6 - mat.m9)*mult;
    result.y = (mat.m8 - mat.m2)*mult;
    result.z = (mat.m1 - mat.m4)*mult;
    break;
  case 1:
    result.x = biggestVal;
    result.w = (mat.m6 - mat.m9)*mult;
    result.y = (mat.m1 + mat.m4)*mult;
    result.z = (mat.m8 + mat.m2)*mult;
    break;
  case 2:
    result.y = biggestVal;
    result.w = (mat.m8 - mat.m2)*mult;
    result.x = (mat.m1 + mat.m4)*mult;
    result.z = (mat.m6 + mat.m9)*mult;
    break;
  case 3:
    result.z = biggestVal;
    result.w = (mat.m1 - mat.m4)*mult;
    result.x = (mat.m8 + mat.m2)*mult;
    result.y = (mat.m6 + mat.m9)*mult;
    break;
  }

  return result;
}

// Get a matrix for a given quaternion
RMAPI
GETS(Matrix) QuaternionToMatrix(GETS(Quaternion) q)
{
  GETS(Matrix) result = { 1.0f, 0.0f, 0.0f, 0.0f,
                          0.0f, 1.0f, 0.0f, 0.0f,
                          0.0f, 0.0f, 1.0f, 0.0f,
                          0.0f, 0.0f, 0.0f, 1.0f
                        }; // GETS(Matrix)Identity()

  float a2 = q.x*q.x;
  float b2 = q.y*q.y;
  float c2 = q.z*q.z;
  float ac = q.x*q.z;
  float ab = q.x*q.y;
  float bc = q.y*q.z;
  float ad = q.w*q.x;
  float bd = q.w*q.y;
  float cd = q.w*q.z;

  result.m0 = 1 - 2*(b2 + c2);
  result.m1 = 2*(ab + cd);
  result.m2 = 2*(ac - bd);

  result.m4 = 2*(ab - cd);
  result.m5 = 1 - 2*(a2 + c2);
  result.m6 = 2*(bc + ad);

  result.m8 = 2*(ac + bd);
  result.m9 = 2*(bc - ad);
  result.m10 = 1 - 2*(a2 + b2);

  return result;
}

// Get rotation quaternion for an angle and axis
// NOTE: Angle must be provided in radians
RMAPI
GETS(Quaternion) QuaternionFromAxisAngle(GETS(Vector3) axis, float angle)
{
  GETS(Quaternion) result = { 0.0f, 0.0f, 0.0f, 1.0f };

  float axisLength = sqrtf(axis.x*axis.x + axis.y*axis.y + axis.z*axis.z);

  if (axisLength != 0.0f) {
    angle *= 0.5f;

    float length = 0.0f;
    float ilength = 0.0f;

    // GETS(Vector3)Normalize(axis)
    length = axisLength;
    if (length == 0.0f) length = 1.0f;
    ilength = 1.0f/length;
    axis.x *= ilength;
    axis.y *= ilength;
    axis.z *= ilength;

    float sinres = sinf(angle);
    float cosres = cosf(angle);

    result.x = axis.x*sinres;
    result.y = axis.y*sinres;
    result.z = axis.z*sinres;
    result.w = cosres;

    // GETS(Quaternion)Normalize(q);
    GETS(Quaternion) q = result;
    length = sqrtf(q.x*q.x + q.y*q.y + q.z*q.z + q.w*q.w);
    if (length == 0.0f) length = 1.0f;
    ilength = 1.0f/length;
    result.x = q.x*ilength;
    result.y = q.y*ilength;
    result.z = q.z*ilength;
    result.w = q.w*ilength;
  }

  return result;
}

// Get the rotation angle and axis for a given quaternion
RMAPI void
QuaternionToAxisAngle(GETS(Quaternion) q, GETS(Vector3) *outAxis, float *outAngle)
{
  if (fabsf(q.w) > 1.0f) {
    // GETS(Quaternion)Normalize(q);
    float length = sqrtf(q.x*q.x + q.y*q.y + q.z*q.z + q.w*q.w);
    if (length == 0.0f) length = 1.0f;
    float ilength = 1.0f/length;

    q.x = q.x*ilength;
    q.y = q.y*ilength;
    q.z = q.z*ilength;
    q.w = q.w*ilength;
  }

  GETS(Vector3) resAxis = { 0.0f, 0.0f, 0.0f };
  float resAngle = 2.0f*acosf(q.w);
  float den = sqrtf(1.0f - q.w*q.w);

  if (den > EPSILON) {
    resAxis.x = q.x/den;
    resAxis.y = q.y/den;
    resAxis.z = q.z/den;
  } else {
    // This occurs when the angle is zero.
    // Not a problem: just set an arbitrary normalized axis.
    resAxis.x = 1.0f;
  }

  *outAxis = resAxis;
  *outAngle = resAngle;
}

// Get the quaternion equivalent to Euler angles
// NOTE: Rotation order is ZYX
RMAPI
GETS(Quaternion) QuaternionFromEuler(float pitch, float yaw, float roll)
{
  GETS(Quaternion) result = { 0 };

  float x0 = cosf(pitch*0.5f);
  float x1 = sinf(pitch*0.5f);
  float y0 = cosf(yaw*0.5f);
  float y1 = sinf(yaw*0.5f);
  float z0 = cosf(roll*0.5f);
  float z1 = sinf(roll*0.5f);

  result.x = x1*y0*z0 - x0*y1*z1;
  result.y = x0*y1*z0 + x1*y0*z1;
  result.z = x0*y0*z1 - x1*y1*z0;
  result.w = x0*y0*z0 + x1*y1*z1;

  return result;
}

// Get the Euler angles equivalent to quaternion (roll, pitch, yaw)
// NOTE: Angles are returned in a GETS(Vector3) struct in radians
RMAPI
GETS(Vector3) QuaternionToEuler(GETS(Quaternion) q)
{
  GETS(Vector3) result = { 0 };

  // Roll (x-axis rotation)
  float x0 = 2.0f*(q.w*q.x + q.y*q.z);
  float x1 = 1.0f - 2.0f*(q.x*q.x + q.y*q.y);
  result.x = atan2f(x0, x1);

  // Pitch (y-axis rotation)
  float y0 = 2.0f*(q.w*q.y - q.z*q.x);
  y0 = y0 > 1.0f ? 1.0f : y0;
  y0 = y0 < -1.0f ? -1.0f : y0;
  result.y = asinf(y0);

  // Yaw (z-axis rotation)
  float z0 = 2.0f*(q.w*q.z + q.x*q.y);
  float z1 = 1.0f - 2.0f*(q.y*q.y + q.z*q.z);
  result.z = atan2f(z0, z1);

  return result;
}

// Transform a quaternion given a transformation matrix
RMAPI
GETS(Quaternion) QuaternionTransform(GETS(Quaternion) q, GETS(Matrix) mat)
{
  GETS(Quaternion) result = { 0 };

  result.x = mat.m0*q.x + mat.m4*q.y + mat.m8*q.z + mat.m12*q.w;
  result.y = mat.m1*q.x + mat.m5*q.y + mat.m9*q.z + mat.m13*q.w;
  result.z = mat.m2*q.x + mat.m6*q.y + mat.m10*q.z + mat.m14*q.w;
  result.w = mat.m3*q.x + mat.m7*q.y + mat.m11*q.z + mat.m15*q.w;

  return result;
}

// Check whether two given quaternions are almost equal
RMAPI int
QuaternionEquals(GETS(Quaternion) p, GETS(Quaternion) q)
{
#if !defined(EPSILON)
#define EPSILON 0.000001f
#endif

  int result = (((fabsf(p.x - q.x)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.x), fabsf(q.x))))) &&
                ((fabsf(p.y - q.y)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.y), fabsf(q.y))))) &&
                ((fabsf(p.z - q.z)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.z), fabsf(q.z))))) &&
                ((fabsf(p.w - q.w)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.w), fabsf(q.w)))))) ||
               (((fabsf(p.x + q.x)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.x), fabsf(q.x))))) &&
                ((fabsf(p.y + q.y)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.y), fabsf(q.y))))) &&
                ((fabsf(p.z + q.z)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.z), fabsf(q.z))))) &&
                ((fabsf(p.w + q.w)) <= (EPSILON*fmaxf(1.0f, fmaxf(fabsf(p.w), fabsf(q.w))))));

  return result;
}

#endif  // RAYMATH_H