AutoScale.cpp

00001 #include "AutoScale.h"
00002 #include <algorithm> 
00003 
00004 AutoScale::AutoScale(AnalogFilterInterface *chain,long expectedMin, long expectedMax) :
00005     AnalogFilterInterface(chain), _expectedMax(expectedMax), _expectedMin(expectedMin), _currentMax(expectedMin), _currentMin(expectedMax), _current(0), _a(0.), _b(0), _mul(1.0)
00006 {
00007 }
00008 AutoScale::AutoScale(AnalogFilterInterface *chain,long expectedMin, long expectedMax, double multiplier) :
00009     AnalogFilterInterface(chain), _expectedMax(expectedMax), _expectedMin(expectedMin), _currentMax(expectedMin), _currentMin(expectedMax), _current(0), _a(0.), _b(0), _mul(multiplier)
00010 {
00011 }
00012 
00013 AutoScale::~AutoScale()
00014 {
00015 }
00016 
00017 void AutoScale::setData(long dataPoint)
00018 {
00019     getChain()->setData(dataPoint);
00020     _current = getChain()->getData();
00021 
00022     if (_current < _currentMin) {
00023         _currentMin = _current;
00024         reCalc();
00025     }
00026     if (_current > _currentMax) {
00027         _currentMax = _current;
00028         reCalc();
00029     }
00030     _current = (long)((_a * _current + _b)*_mul);
00031 
00032     _current = std::min(_current, _expectedMax);
00033     _current = std::max(_current, _expectedMin);
00034 }
00035 
00036 long AutoScale::getData() const
00037 {
00038     return _current;
00039 }
00040 
00041 void AutoScale::reCalc()
00042 {
00043     _a = (_expectedMax - _expectedMin) / (double)(_currentMax - _currentMin);
00044     _b = -((_a * _currentMax) - _expectedMax);
00045 }
00046