citra-nightly/src/core/perf_stats.h
2017-02-26 17:22:04 -08:00

84 lines
2.6 KiB
C++

// Copyright 2017 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <chrono>
#include <mutex>
#include "common/common_types.h"
namespace Core {
/**
* Class to manage and query performance/timing statistics. All public functions of this class are
* thread-safe unless stated otherwise.
*/
class PerfStats {
public:
using Clock = std::chrono::high_resolution_clock;
struct Results {
/// System FPS (LCD VBlanks) in Hz
double system_fps;
/// Game FPS (GSP frame submissions) in Hz
double game_fps;
/// Walltime per system frame, in seconds, excluding any waits
double frametime;
/// Ratio of walltime / emulated time elapsed
double emulation_speed;
};
void BeginSystemFrame();
void EndSystemFrame();
void EndGameFrame();
Results GetAndResetStats(u64 current_system_time_us);
/**
* Gets the ratio between walltime and the emulated time of the previous system frame. This is
* useful for scaling inputs or outputs moving between the two time domains.
*/
double GetLastFrameTimeScale();
private:
std::mutex object_mutex;
/// Point when the cumulative counters were reset
Clock::time_point reset_point = Clock::now();
/// System time when the cumulative counters were reset
u64 reset_point_system_us = 0;
/// Cumulative duration (excluding v-sync/frame-limiting) of frames since last reset
Clock::duration accumulated_frametime = Clock::duration::zero();
/// Cumulative number of system frames (LCD VBlanks) presented since last reset
u32 system_frames = 0;
/// Cumulative number of game frames (GSP frame submissions) since last reset
u32 game_frames = 0;
/// Point when the previous system frame ended
Clock::time_point previous_frame_end = reset_point;
/// Point when the current system frame began
Clock::time_point frame_begin = reset_point;
/// Total visible duration (including frame-limiting, etc.) of the previous system frame
Clock::duration previous_frame_length = Clock::duration::zero();
};
class FrameLimiter {
public:
using Clock = std::chrono::high_resolution_clock;
void DoFrameLimiting(u64 current_system_time_us);
private:
/// Emulated system time (in microseconds) at the last limiter invocation
u64 previous_system_time_us = 0;
/// Walltime at the last limiter invocation
Clock::time_point previous_walltime = Clock::now();
/// Accumulated difference between walltime and emulated time
std::chrono::microseconds frame_limiting_delta_err{0};
};
} // namespace Core