1 files changed, 140 insertions, 0 deletions
diff --git a/engine/enginestats.h b/engine/enginestats.h
new file mode 100644
index 0000000..f3e29fe
--- /dev/null
+++ b/engine/enginestats.h
@@ -0,0 +1,140 @@
+//========= Copyright Valve Corporation, All rights reserved. ============//
+//
+// Purpose: 
+//
+// $NoKeywords: $
+//=============================================================================//
+
+#ifndef ENGINESTATS_H
+#define ENGINESTATS_H
+
+#ifdef _WIN32
+#pragma once
+#endif
+
+#include "utlvector.h"
+#include "sysexternal.h"
+#include "filesystem.h" // FileHandle_t define
+
+enum EngineTimedStatId_t
+{
+	ENGINE_STATS_FRAME_TIME,
+	ENGINE_STATS_FPS, // this is calculated at EndFrame!
+	ENGINE_STATS_FPS_VARIABILITY,
+	ENGINE_STATS_NUM_TIMED_STATS,
+};
+class CEngineStats
+{
+public:
+	CEngineStats();
+
+	//
+	// stats input
+	//
+
+	void BeginRun( void );
+
+	// Advances the next frame for the stats...
+	void NextFrame(); 
+
+	void BeginFrame( void );
+
+	// Timed stat gathering
+	void BeginTimedStat( EngineTimedStatId_t stat );
+	void EndTimedStat( EngineTimedStatId_t stat );
+
+	// Adds to a timed stat...
+	void AddToTimedStat( EngineTimedStatId_t stat, float time );
+
+	// Slams a timed stat
+	void SetTimedStat( EngineTimedStatId_t stat, float time );
+
+	// returns timed stats
+	double TimedStatInFrame( EngineTimedStatId_t stat ) const;
+	double TotalTimedStat( EngineTimedStatId_t stat ) const;
+
+	void BeginDrawWorld( void );
+	void EndDrawWorld( void );
+
+	void EndFrame( void );
+	void EndRun( void );
+
+	void PauseStats( bool bPaused );
+
+	//
+	// stats output
+	// call these outside of a BeginFrame/EndFrame pair
+	//
+
+	double GetRunTime( void );
+	
+	void SetFrameTime( float flFrameTime ) { m_flFrameTime = flFrameTime; }
+	void SetFPSVariability( float flFPSVariability ) { m_flFPSVariability = flFPSVariability; }
+
+	int FrameCount() const { return m_totalNumFrames; }
+
+private:
+	void ComputeFrameTimeStats( void );
+
+	// How many frames worth of data have we logged?
+	int m_totalNumFrames;
+
+	// run timing data
+	double m_runStartTime;
+	double m_runEndTime;
+
+	struct StatGroupInfo_t
+	{
+		double m_StatFrameTime[ENGINE_STATS_NUM_TIMED_STATS];
+		double m_StatStartTime[ENGINE_STATS_NUM_TIMED_STATS];
+		double m_TotalStatTime[ENGINE_STATS_NUM_TIMED_STATS];
+	};
+	StatGroupInfo_t m_StatGroup;
+	bool m_InFrame;
+
+	bool m_bPaused;
+	bool m_bInRun;
+
+	float m_flFrameTime;
+	float m_flFPSVariability;
+};
+
+
+//-----------------------------------------------------------------------------
+// Inlined stat gathering methods
+//-----------------------------------------------------------------------------
+inline void CEngineStats::BeginTimedStat( EngineTimedStatId_t stat )
+{
+	if (m_InFrame)
+	{
+		m_StatGroup.m_StatStartTime[stat] = 
+			Sys_FloatTime();
+	}
+}
+
+inline void CEngineStats::EndTimedStat( EngineTimedStatId_t stat )
+{
+	if (m_InFrame)
+	{
+		float dt = (float)Sys_FloatTime() - (float)(m_StatGroup.m_StatStartTime[stat]);
+		m_StatGroup.m_StatFrameTime[stat] += dt; 
+	}
+}
+
+// Adds to a timed stat...
+inline void CEngineStats::AddToTimedStat( EngineTimedStatId_t stat, float dt )
+{
+	if (m_InFrame)
+	{
+		m_StatGroup.m_StatFrameTime[stat] += dt; 
+	}
+}
+
+// Slams a timed stat
+inline void CEngineStats::SetTimedStat( EngineTimedStatId_t stat, float time )
+{
+	m_StatGroup.m_StatFrameTime[stat] = time; 
+}
+extern CEngineStats g_EngineStats;
+
+#endif // ENGINESTATS_H