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// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef UI_GL_SYNC_CONTROL_VSYNC_PROVIDER_H_
#define UI_GL_SYNC_CONTROL_VSYNC_PROVIDER_H_
#include <stdint.h>
#include "base/containers/queue.h"
#include "base/time/time.h"
#include "build/build_config.h"
#include "ui/gfx/vsync_provider.h"
namespace gl {
// Base class for providers based on extensions like GLX_OML_sync_control and
// EGL_CHROMIUM_sync_control.
class SyncControlVSyncProvider : public gfx::VSyncProvider {
public:
SyncControlVSyncProvider();
SyncControlVSyncProvider(const SyncControlVSyncProvider&) = delete;
SyncControlVSyncProvider& operator=(const SyncControlVSyncProvider&) = delete;
~SyncControlVSyncProvider() override;
void GetVSyncParameters(UpdateVSyncCallback callback) override;
bool GetVSyncParametersIfAvailable(base::TimeTicks* timebase,
base::TimeDelta* interval) override;
bool SupportGetVSyncParametersIfAvailable() const override;
static constexpr bool IsSupported() {
#if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
return true;
#else
return false;
#endif // BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
}
protected:
virtual bool GetSyncValues(int64_t* system_time,
int64_t* media_stream_counter,
int64_t* swap_buffer_counter) = 0;
virtual bool GetMscRate(int32_t* numerator, int32_t* denominator) = 0;
private:
#if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
base::TimeTicks last_timebase_;
uint64_t last_media_stream_counter_ = 0;
base::TimeDelta last_good_interval_;
bool invalid_msc_ = false;
// A short history of the last few computed intervals.
// We use this to filter out the noise in the computation resulting
// from configuration change (monitor reconfiguration, moving windows
// between monitors, suspend and resume, etc.).
base::queue<base::TimeDelta> last_computed_intervals_;
#endif // BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
};
} // namespace gl
#endif // UI_GL_SYNC_CONTROL_VSYNC_PROVIDER_H_
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