GY-63_MS5611/libraries/FastTrig/FastTrig.h
2022-12-08 17:32:53 +01:00

72 lines
1.3 KiB
C

#pragma once
//
// FILE: FastTrig.h
// AUTHOR: Rob Tillaart
// VERSION: 0.2.1
// PURPOSE: Arduino library for a faster approximation of sin() and cos()
// DATE: 2011-08-18
// URL: https://github.com/RobTillaart/FastTrig
// https://forum.arduino.cc/index.php?topic=69723.0
#ifdef ESP_PLATFORM
#include <math.h>
#include <stdint.h>
#include <stdbool.h>
#else
#include "Arduino.h"
#endif
#define FAST_TRIG_LIB_VERSION (F("0.2.1"))
#ifdef __cplusplus
extern "C"
{
#endif
extern uint16_t sinTable16[];
extern uint8_t sinTable8[];
///////////////////////////////////////////////////////
//
// GONIO LOOKUP
//
float isin(float f);
float icos(float x);
float itan(float f);
// 0 returns NAN but we have a icot(x) cotangent.
float icot(float f);
///////////////////////////////////////////////////////
//
// INVERSE GONIO LOOKUP
//
float iasin(float f);
float iacos(float f);
// PLACEHOLDER (might be obsolete due to atanFast() formula.
float iatan(float f);
// fast atan() formula, in fact a modified Taylor expansion
// input = -1 .. 1
float atanFast(float f);
inline float atanHelper(float x);
// atan2Fast() folds and mirrors => calls atanFast() + offset.
float atan2Fast(float y, float x);
#ifdef __cplusplus
}
#endif
// -- END OF FILE --