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// Copyright (C) 2015 Paul Lemire
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include "vsyncframeadvanceservice_p.h"
#include <Qt3DRender/private/renderlogging_p.h>
#include <Qt3DCore/private/qabstractframeadvanceservice_p.h>
#include <Qt3DCore/private/qabstractframeadvanceservice_p_p.h>
#include <QSemaphore>
#include <QElapsedTimer>
QT_BEGIN_NAMESPACE
namespace Qt3DRender {
namespace Render {
class VSyncFrameAdvanceServicePrivate final : public Qt3DCore::QAbstractFrameAdvanceServicePrivate
{
public:
explicit VSyncFrameAdvanceServicePrivate(bool drivenByRenderThread)
: QAbstractFrameAdvanceServicePrivate(QStringLiteral("Renderer Aspect Frame Advance Service - aligned with vsync"))
, m_semaphore(0)
, m_elapsedTimeSincePreviousFrame(0)
, m_drivenByRenderThread(drivenByRenderThread)
{
}
QSemaphore m_semaphore;
QElapsedTimer m_elapsed;
qint64 m_elapsedTimeSincePreviousFrame;
bool m_drivenByRenderThread;
};
VSyncFrameAdvanceService::VSyncFrameAdvanceService(bool drivenByRenderThread)
: QAbstractFrameAdvanceService(*new VSyncFrameAdvanceServicePrivate(drivenByRenderThread))
{
}
VSyncFrameAdvanceService::~VSyncFrameAdvanceService()
{
}
// Main Thread
qint64 VSyncFrameAdvanceService::waitForNextFrame()
{
Q_D(VSyncFrameAdvanceService);
d->m_semaphore.acquire(std::max(d->m_semaphore.available(), 1));
const qint64 currentTime = d->m_elapsed.nsecsElapsed();
qCDebug(VSyncAdvanceService) << "Elapsed nsecs since last call " << currentTime - d->m_elapsedTimeSincePreviousFrame;
d->m_elapsedTimeSincePreviousFrame = currentTime;
return currentTime;
}
void VSyncFrameAdvanceService::start()
{
Q_D(VSyncFrameAdvanceService);
d->m_elapsed.start();
}
/*!
\internal
Stops the VSyncFrameAdvanceService, releases the semaphore to allow the
renderer to cleanup without having to call waitForNextFrame.
*/
void VSyncFrameAdvanceService::stop()
{
Q_D(VSyncFrameAdvanceService);
d->m_semaphore.release(1);
qCDebug(VSyncAdvanceService) << "Terminating VSyncFrameAdvanceService";
}
// Render Thread
void VSyncFrameAdvanceService::proceedToNextFrame()
{
Q_D(VSyncFrameAdvanceService);
d->m_semaphore.release(1);
}
} // namespace Render
} // namespace Qt3DRender
QT_END_NAMESPACE