$#include "MathDefs.h"

static const float M_PI;

static const int M_MIN_INT;
static const int M_MAX_INT;
static const unsigned M_MIN_UNSIGNED;
static const unsigned M_MAX_UNSIGNED;

static const float M_EPSILON;
static const float M_LARGE_EPSILON;
static const float M_MIN_NEARCLIP;
static const float M_MAX_FOV;
static const float M_LARGE_VALUE;
static const float M_INFINITY;
static const float M_DEGTORAD;
static const float M_DEGTORAD_2;
static const float M_RADTODEG;

/// Intersection test result.
enum Intersection
{
    OUTSIDE,
    INTERSECTS,
    INSIDE
};

/// Linear interpolation between two float values.
inline float Lerp(float lhs, float rhs, float t) { return lhs * (1.0f - t) + rhs * t; }
/// Return the smaller of two floats.
inline float Min(float lhs, float rhs) { return lhs < rhs ? lhs : rhs; }
/// Return the larger of two floats.
inline float Max(float lhs, float rhs) { return lhs > rhs ? lhs : rhs; }
/// Return absolute value of a float.
inline float Abs(float value) { return value >= 0.0f ? value : -value; }

/// Clamp a float to a range.
inline float Clamp(float value, float min, float max)
{
    if (value < min)
        return min;
    else if (value > max)
        return max;
    else
        return value;
}

/// Check whether two floating point values are equal within accuracy.
inline bool Equals(float lhs, float rhs) { return lhs + M_EPSILON >= rhs && lhs - M_EPSILON <= rhs; }
/// Return the smaller of two integers.
inline int Min(int lhs, int rhs) { return lhs < rhs ? lhs : rhs; }
/// Return the larger of two integers.
inline int Max(int lhs, int rhs) { return lhs > rhs ? lhs : rhs; }
/// Return absolute value of an integer
inline int Abs(int value) { return value >= 0 ? value : -value; }

/// Clamp an integer to a range.
inline int Clamp(int value, int min, int max)
{
    if (value < min)
        return min;
    else if (value > max)
        return max;
    else
        return value;
}

/// Check whether an unsigned integer is a power of two.
inline bool IsPowerOfTwo(unsigned value)
{
    if (!value)
        return true;
    while (!(value & 1))
        value >>= 1;
    return value == 1;
}

/// Round up to next power of two.
inline unsigned NextPowerOfTwo(unsigned value)
{
    unsigned ret = 1;
    while (ret < value && ret < 0x80000000)
        ret <<= 1;
    return ret;
}

/// Update a hash with the given 8-bit value using the SDBM algorithm.
inline unsigned SDBMHash(unsigned hash, unsigned char c) { return c + (hash << 6) + (hash << 16) - hash; }
/// Return a random float between 0.0 (inclusive) and 1.0 (exclusive.)
inline float Random() { return Rand() / 32768.0f; }
/// Return a random float between 0.0 and range, inclusive from both ends.
inline float Random(float range) { return Rand() * range / 32767.0f; }
/// Return a random integer between 0 and range - 1.
inline int Random @ RandomInt(int range) { return (Rand() * (range - 1) + 16384) / 32767; }