frequency_filter.h

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/* Copyright (C) 2022 Wildfire Games.
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#ifndef INCLUDED_FREQUENCY_FILTER
#define INCLUDED_FREQUENCY_FILTER
 
// calculate frequency of events (tuned for 100 Hz)
struct IFrequencyFilter
{
    virtual ~IFrequencyFilter() {}
 
    virtual void Update(double value) = 0;
 
    // smoothed but rapidly tracked frequency
    virtual double SmoothedFrequency() const = 0;
 
    // stable, non-fluctuating value for user display
    virtual int StableFrequency() const = 0;
};
 
typedef std::shared_ptr<IFrequencyFilter> PIFrequencyFilter;
 
// expectedFrequency is a guess that hopefully speeds up convergence
PIFrequencyFilter CreateFrequencyFilter(double resolution, double expectedFrequency);
 
#endif  // #ifndef INCLUDED_FREQUENCY_FILTER