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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
#include "fpshelper.h"
FpsHelper::FpsHelper()
{
setFlag(QQuickItem::ItemHasContents);
connect(this, &QQuickItem::enabledChanged, this, [this]() {
if (isEnabled()) {
m_frames = 0;
m_timer.start();
update();
}
});
if (isEnabled())
m_timer.start();
}
float FpsHelper::fps() const
{
return m_fps;
}
QSGNode *FpsHelper::updatePaintNode(QSGNode *node, UpdatePaintNodeData *)
{
m_frames++;
qint64 nsElapsed = m_timer.nsecsElapsed();
float ms = float(nsElapsed / 1000000.0);
if (ms >= 1000.0f) {
float fps = m_frames / (ms / 1000.0f);
// Round to 0.2 accuracy
fps = std::round(fps * 5.0f) / 5.0f;
if (!qFuzzyCompare(fps, m_fps)) {
m_fps = fps;
Q_EMIT fpsChanged();
}
m_frames = 0;
m_timer.restart();
}
// Call update in a loop if fps tracking is enabled
if (isEnabled())
update();
return node;
}