OpenMW/components/misc/budgetmeasurement.hpp

#ifndef OPENMW_COMPONENTS_MISC_BUDGETMEASUREMENT_H
#define OPENMW_COMPONENTS_MISC_BUDGETMEASUREMENT_H

#include <array>
#include <cstddef>

namespace Misc
{

    class BudgetMeasurement
    {
        std::array<float, 4> mBudgetHistory;
        std::array<unsigned int, 4> mBudgetStepCount;

    public:
        BudgetMeasurement(const float default_expense)
        {
            mBudgetHistory = { default_expense, default_expense, default_expense, default_expense };
            mBudgetStepCount = { 1, 1, 1, 1 };
        }

        void reset(const float default_expense)
        {
            mBudgetHistory = { default_expense, default_expense, default_expense, default_expense };
            mBudgetStepCount = { 1, 1, 1, 1 };
        }

        void update(double delta, unsigned int stepCount, size_t cursor)
        {
            mBudgetHistory[cursor % 4] = delta;
            mBudgetStepCount[cursor % 4] = stepCount;
        }

        double get() const
        {
            float sum = (mBudgetHistory[0] + mBudgetHistory[1] + mBudgetHistory[2] + mBudgetHistory[3]);
            unsigned int stepCountSum
                = (mBudgetStepCount[0] + mBudgetStepCount[1] + mBudgetStepCount[2] + mBudgetStepCount[3]);
            return sum / float(stepCountSum);
        }
    };

}

#endif