mirror of
https://github.com/RobTillaart/Arduino.git
synced 2024-09-20 00:55:58 -04:00
97 lines
2.3 KiB
C++
97 lines
2.3 KiB
C++
#pragma once
|
|
//
|
|
// FILE: MultiMap.h
|
|
// AUTHOR: Rob Tillaart
|
|
// VERSION: 0.1.4
|
|
// DATE: 2011-01-26
|
|
// PURPOSE: Arduino library for fast non-linear mapping or interpolation of values
|
|
// URL: https://github.com/RobTillaart/MultiMap
|
|
// URL: http://playground.arduino.cc/Main/MultiMap
|
|
//
|
|
// HISTORY:
|
|
// 0.0.1 2011-01-26 initial version (see forum)
|
|
// .....
|
|
// 0.1.0 2015-03-29
|
|
// 0.1.1 2020-04-09
|
|
// 0.1.2 2020-06-19 fix library.json
|
|
// 0.1.3 2021-01-02 add arduino-CI
|
|
// 0.1.4 2021-05-27 fix arduino-lint
|
|
|
|
|
|
#define MULTIMAP_LIB_VERSION (F("0.1.4"))
|
|
|
|
|
|
#include "Arduino.h"
|
|
|
|
// note: the in array should have increasing values
|
|
template<typename T>
|
|
T multiMap(T val, T* _in, T* _out, uint8_t size)
|
|
{
|
|
// take care the value is within range
|
|
// val = constrain(val, _in[0], _in[size-1]);
|
|
if (val <= _in[0]) return _out[0];
|
|
if (val >= _in[size-1]) return _out[size-1];
|
|
|
|
// search right interval
|
|
uint8_t pos = 1; // _in[0] allready tested
|
|
while(val > _in[pos]) pos++;
|
|
|
|
// this will handle all exact "points" in the _in array
|
|
if (val == _in[pos]) return _out[pos];
|
|
|
|
// interpolate in the right segment for the rest
|
|
return (val - _in[pos-1]) * (_out[pos] - _out[pos-1]) / (_in[pos] - _in[pos-1]) + _out[pos-1];
|
|
}
|
|
|
|
|
|
/*
|
|
* speed optimized version if inputs do not change often e.g. 2 2 2 2 2 3 3 3 3 5 5 5 5 5 5 8 8 8 8 5 5 5 5 5
|
|
*
|
|
// note: the in array should have increasing values
|
|
|
|
template<typename T>
|
|
T multiMap(T val, T* _in, T* _out, uint8_t size)
|
|
{
|
|
static T lastvalue = -1;
|
|
static T cache = -1;
|
|
|
|
if (val == lastvalue)
|
|
{
|
|
return cache;
|
|
}
|
|
lastvalue = val;
|
|
|
|
// take care the value is within range
|
|
// val = constrain(val, _in[0], _in[size-1]);
|
|
if (val <= _in[0])
|
|
{
|
|
cache = _out[0];
|
|
}
|
|
else if (val >= _in[size-1])
|
|
{
|
|
cache = _out[size-1];
|
|
}
|
|
else
|
|
{
|
|
// search right interval; index 0 _in[0] already tested
|
|
uint8_t pos = 1;
|
|
while(val > _in[pos]) pos++;
|
|
|
|
// this will handle all exact "points" in the _in array
|
|
if (val == _in[pos])
|
|
{
|
|
cache = _out[pos];
|
|
}
|
|
else
|
|
{
|
|
// interpolate in the right segment for the rest
|
|
cache = (val - _in[pos-1]) * (_out[pos] - _out[pos-1]) / (_in[pos] - _in[pos-1]) + _out[pos-1];
|
|
}
|
|
}
|
|
return cache;
|
|
}
|
|
*/
|
|
|
|
|
|
// -- END OF FILE --
|