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 * OpenSpace                                                                             *
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 * Copyright (c) 2014-2021                                                               *
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#ifndef __OPENSPACE_MODULE_AUTONAVIGATION___SPEEDFUNCTION___H__
#define __OPENSPACE_MODULE_AUTONAVIGATION___SPEEDFUNCTION___H__

namespace openspace::autonavigation {

// The speed function describing the shape of the speed curve. Values in [0,1].
class SpeedFunction {
public:
    enum class Type {
        DampenedQuintic,
        DampenedSextic
    };

    SpeedFunction(Type type = Type::DampenedQuintic);
    virtual ~SpeedFunction();

    double scaledValue(double time, double duration, double pathLength) const;

    virtual double value(double t) const;

protected:
    void initializeIntegratedSum();

    // Store the sum of the function over the duration of the segment,
    // so we don't need to recompue it every time we access the speed
    double _integratedSum = 0.0;

    Type _type;
};

} // namespace openspace::autonavigation

#endif // __OPENSPACE_MODULE_AUTONAVIGATION___SPEEDFUNCTION___H__