SchmittTriggerHysteresis.h

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/*
 * Copyright (C) 2012 by
 *   MetraLabs GmbH (MLAB), GERMANY
 * and
 *   Neuroinformatics and Cognitive Robotics Labs (NICR) at TU Ilmenau, GERMANY
 * All rights reserved.
 *
 * Contact: info@mira-project.org
 *
 * Commercial Usage:
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 *   software or, alternatively, in accordance with the terms contained in
 *   a written agreement between you and MLAB or NICR.
 *
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 *   Foundation and appearing in the file LICENSE.GPL3 included in the
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#ifndef _MIRA_SCHMITTTRIGGERHYSTERESIS_H_
#define _MIRA_SCHMITTTRIGGERHYSTERESIS_H_

namespace mira
{


template <typename T>
class SchmittTriggerHysteresis
{
public:
    enum State
    {
        UNKNOWN,
        LOW,
        HIGH
    };

    SchmittTriggerHysteresis() :
        mState(UNKNOWN)
    {}

    SchmittTriggerHysteresis(State state) :
        mState(state)
    {}

    SchmittTriggerHysteresis(const T& lower, const T& upper) :
        mState(UNKNOWN),
        mLowerThreshold(lower<=upper?lower:upper),
        mUpperThreshold(upper>=lower?upper:lower)
    {}

    SchmittTriggerHysteresis(State state, const T& lower, const T& upper) :
        mState(state),
        mLowerThreshold(lower<=upper?lower:upper),
        mUpperThreshold(upper>=lower?upper:lower)
    {}

    template <typename Reflector>
    void reflect(Reflector& r)
    {
        r.property("Lower", mLowerThreshold, "Lower threshold");
        r.property("Upper", mUpperThreshold, "Upper threshold");
        r.member("State", mState, "The state", UNKNOWN);
    }

    bool update(const T& value)
    {
        State oldState = mState;
        if (value < mLowerThreshold)
            mState = LOW;
        if (value > mUpperThreshold)
            mState = HIGH;
        if (mState != oldState)
            return true;
        return false;
    }

    State getState() const
    {
        return mState;
    }

private:
    State mState;
    T mLowerThreshold;
    T mUpperThreshold;
};


}

#endif