math.h

/* ScummVM - Graphic Adventure Engine
 *
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 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
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 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
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 *
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 */

//=============================================================================
//
// Helper math functions
//
//=============================================================================

#ifndef AGS_SHARED_UTIL_MATH_H
#define AGS_SHARED_UTIL_MATH_H

#include "common/std/limits.h"

#include "ags/lib/std.h"

namespace AGS3 {

#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif

namespace AGS {
namespace Shared {

namespace Math {
template <class T>
inline const T &Max(const T &a, const T &b) {
    return a < b ? b : a;
}

template <class T>
inline const T &Min(const T &a, const T &b) {
    return a < b ? a : b;
}

template <class T>
inline const T &Clamp(const T &val, const T &floor, const T &ceil) {
    return Max<T>(floor, Min<T>(val, ceil));
}

template <class T>
inline void ClampLength(T &from, T &length, const T &floor, const T &height) {
    if (from < floor) {
        length -= floor - from;
        from = floor;
    } else if (from >= floor + height) {
        from = floor + height;
        length = 0;
    }

    length = Max<T>(length, 0);
    length = Min<T>(length, height - from);
}

// Get a measure of how value A is greater than value B;
// if A is smaller than or equal to B, returns 0.
template <class T>
inline T Surplus(const T &larger, const T &smaller) {
    return larger > smaller ? larger - smaller : 0;
}

// Tests if the big-type value is in range of the result type;
// returns same value converted if it's in range, or provided replacement if it's not.
template <typename T, typename TBig>
inline T InRangeOrDef(const TBig &val, const T &def) {
    return (val >= std::numeric_limits<T>::min() && val <= std::numeric_limits<T>::max()) ?
        static_cast<T>(val) : def;
}

inline float RadiansToDegrees(float rads) {
    return rads * (float)(180.0 / M_PI);
}

inline float DegreesToRadians(float deg) {
    return deg * (float)(M_PI / 180.0);
}

} // namespace Math

} // namespace Shared
} // namespace AGS
} // namespace AGS3

#endif