/home/travis/build/lis-epfl/MAVRIC_Library/util/quick_trig.hpp

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/*******************************************************************************
 * \file quick_trig.h
 *
 * \author MAV'RIC Team
 * \author Julien Lecoeur
 *
 * \brief Quick implementation of trigonometric functions
 *
 ******************************************************************************/


#ifndef QUICK_TRIG_H_
#define QUICK_TRIG_H_

#ifdef __cplusplus
extern "C"
{
#endif

#include "util/maths.h"


#define INTERP_POINTS 50


float quick_trig_sin(float x);


float quick_trig_cos(float x);


float quick_trig_acos(float x);


float quick_trig_asin(float x);


float quick_trig_tan(float x);


float quick_trig_atan(float x);


static inline float quick_trig_func(float x, const float func_x_min, const float func_x_max, float func_x_step, const float func_y[])
{
    float y;
    int32_t i;

    if (x <= func_x_min)
    {
        y = func_y[0];
    }
    else if (x >= func_x_max)
    {
        y = func_y[INTERP_POINTS - 1];
    }
    else
    {
        i = (int32_t)((x - func_x_min) / func_x_step);
        y = maths_interpolate(x,
                              func_x_min + i * func_x_step,
                              func_x_min + (i + 1) * func_x_step,
                              func_y[i],
                              func_y[i + 1]);
    }
    return y;
}

#ifdef __cplusplus
}
#endif

#endif /* QUICK_TRIG_H_ */