utility: Added Tracer for collecting time measurements

* define TRACING_ENABLED in utility/tracing.h to enable tracing
* invoke TraceEvent by writing TRACE() at start of function or scope
* provide an event name with TRACE("name")
* press SPACE to show collected traces history and report with accumulated times

src/lib/utility/tracing.h

@@ -0,0 +1,82 @@
+#ifndef TRACING_H
+#define TRACING_H
+
+#include <stack>
+#include <thread>
+
+#include "utility/TimePoint.h"
+#include "utility/types.h"
+
+struct TraceEvent
+{
+public:
+	TraceEvent(const std::string& eventName, Id id, size_t depth)
+		: eventName(eventName)
+		, id(id)
+		, depth(depth)
+		, time(0.0f)
+	{
+	}
+
+	const std::string eventName;
+	const Id id;
+	const size_t depth;
+
+	std::string functionName;
+	std::string locationName;
+
+	float time;
+};
+
+
+class Tracer
+{
+public:
+	static Tracer* getInstance();
+
+	TraceEvent* startEvent(const std::string& eventName);
+	void finishEvent(TraceEvent* event);
+
+	void printTraces();
+
+private:
+	static std::shared_ptr<Tracer> s_instance;
+	static Id s_nextTraceId;
+
+	Tracer();
+	Tracer(const Tracer&);
+	void operator=(const Tracer&);
+
+	std::map<std::thread::id, std::vector<std::shared_ptr<TraceEvent>>> m_events;
+	std::map<std::thread::id, std::stack<TraceEvent*>> m_startedEvents;
+
+	std::mutex m_mutex;
+};
+
+
+class ScopedTrace
+{
+public:
+	ScopedTrace(const std::string& eventName, const std::string& fileName, int lineNumber, const std::string& functionName);
+	~ScopedTrace();
+
+private:
+	TraceEvent* m_event;
+	TimePoint m_timePoint;
+};
+
+
+// #define TRACING_ENABLED
+
+#ifdef TRACING_ENABLED
+	#define TRACE(__name__) \
+		ScopedTrace __trace__(std::string(__name__), __FILE__, __LINE__, __FUNCTION__)
+
+	#define PRINT_TRACES() \
+		Tracer::getInstance()->printTraces()
+#else
+	#define TRACE(__name__)
+	#define PRINT_TRACES()
+#endif
+
+#endif // TRACING_H