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** This file is part of the E-Bike demo project.
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#include <QQuickWindow>

#include "fpscounter.h"

FpsCounter::FpsCounter(QObject *parent)
    : QObject(parent)
    , m_frameCounter(0)
    , m_fps(0.0)
    , m_visible(false)
{
}

void FpsCounter::setVisible(bool visible)
{
    if (m_visible == visible)
        return;

    m_visible = visible;
    emit visibleChanged(m_visible);
}

void FpsCounter::setWindow(QQuickWindow *window)
{
    connect(window, &QQuickWindow::frameSwapped, this, &FpsCounter::frameUpdated);
    startTimer(1000);
    m_timer.start();
}

void FpsCounter::timerEvent(QTimerEvent *)
{
    // Calculate new FPS
    qreal newfps = qRound(m_frameCounter * 1000.0 / m_timer.elapsed());
    m_frameCounter = 0;
    m_timer.start();

    // If there is no change, do nothing
    if (qFuzzyCompare(m_fps, newfps))
        return;

    // Otherwise emit new fps
    m_fps = newfps;
    emit fpsChanged(m_fps);
}