116 lines
2.0 KiB
C++
116 lines
2.0 KiB
C++
// mathlib.h
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//
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// Copyright (C) 2001, Chris Laurel <claurel@shatters.net>
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//
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// This program is free software; you can redistribute it and/or
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// modify it under the terms of the GNU General Public License
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// as published by the Free Software Foundation; either version 2
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// of the License, or (at your option) any later version.
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#ifndef _MATHLIB_H_
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#define _MATHLIB_H_
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#include <cmath>
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#include <stdlib.h>
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#define PI 3.14159265358979323846
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template<class T> class Math
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{
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public:
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static inline void sincos(T, T&, T&);
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static inline T frand();
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static inline T sfrand();
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static inline T lerp(T t, T a, T b);
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static inline T clamp(T t);
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private:
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// This class is static and should not be instantiated
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Math() {};
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};
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typedef Math<float> Mathf;
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typedef Math<double> Mathd;
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template<class T> T degToRad(T d)
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{
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return d / 180 * static_cast<T>(PI);
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}
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template<class T> T radToDeg(T r)
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{
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return r * 180 / static_cast<T>(PI);
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}
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template<class T> T abs(T x)
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{
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return (x < 0) ? -x : x;
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}
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template<class T> T square(T x)
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{
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return x * x;
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}
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template<class T> T clamp(T x)
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{
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if (x < 0)
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return 0;
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else if (x > 1)
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return 1;
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else
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return x;
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}
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template<class T> T circleArea(T r)
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{
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return (T) PI * r * r;
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}
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template<class T> T sphereArea(T r)
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{
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return 4 * (T) PI * r * r;
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}
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template<class T> void Math<T>::sincos(T angle, T& s, T& c)
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{
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s = (T) sin(angle);
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c = (T) cos(angle);
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}
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// return a random float in [0, 1]
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template<class T> T Math<T>::frand()
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{
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return (T) (rand() & 0x7fff) / (T) 32767;
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}
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// return a random float in [-1, 1]
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template<class T> T Math<T>::sfrand()
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{
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return (T) (rand() & 0x7fff) / (T) 32767 * 2 - 1;
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}
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template<class T> T Math<T>::lerp(T t, T a, T b)
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{
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return a + t * (b - a);
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}
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// return t clamped to [0, 1]
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template<class T> T Math<T>::clamp(T t)
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{
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if (t < 0)
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return 0;
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else if (t > 1)
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return 1;
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else
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return t;
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}
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#endif // _MATHLIB_H_
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