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// Copyright 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "config.h"
#include "cc/frame_rate_controller.h"
#include "base/debug/trace_event.h"
#include "base/logging.h"
#include "cc/delay_based_time_source.h"
#include "cc/time_source.h"
namespace {
// This will be the maximum number of pending frames unless
// FrameRateController::setMaxFramesPending is called.
const int defaultMaxFramesPending = 2;
} // namespace
namespace cc {
class FrameRateControllerTimeSourceAdapter : public TimeSourceClient {
public:
static scoped_ptr<FrameRateControllerTimeSourceAdapter> create(FrameRateController* frameRateController) {
return make_scoped_ptr(new FrameRateControllerTimeSourceAdapter(frameRateController));
}
virtual ~FrameRateControllerTimeSourceAdapter() {}
virtual void onTimerTick() OVERRIDE {
m_frameRateController->onTimerTick();
}
private:
explicit FrameRateControllerTimeSourceAdapter(FrameRateController* frameRateController)
: m_frameRateController(frameRateController) {}
FrameRateController* m_frameRateController;
};
FrameRateController::FrameRateController(scoped_refptr<TimeSource> timer)
: m_client(0)
, m_numFramesPending(0)
, m_maxFramesPending(defaultMaxFramesPending)
, m_timeSource(timer)
, m_active(false)
, m_swapBuffersCompleteSupported(true)
, m_isTimeSourceThrottling(true)
{
m_timeSourceClientAdapter = FrameRateControllerTimeSourceAdapter::create(this);
m_timeSource->setClient(m_timeSourceClientAdapter.get());
}
FrameRateController::FrameRateController(Thread* thread)
: m_client(0)
, m_numFramesPending(0)
, m_maxFramesPending(defaultMaxFramesPending)
, m_active(false)
, m_swapBuffersCompleteSupported(true)
, m_isTimeSourceThrottling(false)
, m_manualTicker(new Timer(thread, this))
{
}
FrameRateController::~FrameRateController()
{
if (m_isTimeSourceThrottling)
m_timeSource->setActive(false);
}
void FrameRateController::setActive(bool active)
{
if (m_active == active)
return;
TRACE_EVENT1("cc", "FrameRateController::setActive", "active", active);
m_active = active;
if (m_isTimeSourceThrottling)
m_timeSource->setActive(active);
else {
if (active)
postManualTick();
else
m_manualTicker->stop();
}
}
void FrameRateController::setMaxFramesPending(int maxFramesPending)
{
DCHECK(maxFramesPending > 0);
m_maxFramesPending = maxFramesPending;
}
void FrameRateController::setTimebaseAndInterval(base::TimeTicks timebase, base::TimeDelta interval)
{
if (m_isTimeSourceThrottling)
m_timeSource->setTimebaseAndInterval(timebase, interval);
}
void FrameRateController::setSwapBuffersCompleteSupported(bool supported)
{
m_swapBuffersCompleteSupported = supported;
}
void FrameRateController::onTimerTick()
{
DCHECK(m_active);
// Check if we have too many frames in flight.
bool throttled = m_numFramesPending >= m_maxFramesPending;
if (m_client)
m_client->vsyncTick(throttled);
if (m_swapBuffersCompleteSupported && !m_isTimeSourceThrottling && m_numFramesPending < m_maxFramesPending)
postManualTick();
}
void FrameRateController::postManualTick()
{
if (m_active)
m_manualTicker->startOneShot(0);
}
void FrameRateController::onTimerFired()
{
onTimerTick();
}
void FrameRateController::didBeginFrame()
{
if (m_swapBuffersCompleteSupported)
m_numFramesPending++;
else if (!m_isTimeSourceThrottling)
postManualTick();
}
void FrameRateController::didFinishFrame()
{
DCHECK(m_swapBuffersCompleteSupported);
m_numFramesPending--;
if (!m_isTimeSourceThrottling)
postManualTick();
}
void FrameRateController::didAbortAllPendingFrames()
{
m_numFramesPending = 0;
}
base::TimeTicks FrameRateController::nextTickTime()
{
if (m_isTimeSourceThrottling)
return m_timeSource->nextTickTime();
return base::TimeTicks();
}
}
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