started perf counter

libswan/include/swan/PerfCounter.h

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+namespace Swan {
+
+
+
+class PerfCounter {
+public:
+	class Counter {
+	public:
+		void count(double secs) {
+			latest_ = secs;
+			if (count_ >= 60) {
+				sum_ -= avg();
+				sum_ += secs;
+			} else {
+				sum_ += secs;
+				count_ += 1;
+			}
+		}
+
+		double avg() { return sum_ / count_; }
+		double latest() { return latest_; }
+
+	private:
+		double latest_ = 0;
+		double sum_ = 0;
+		int count_ = 0;
+	};
+
+	void countFrameTime(double secs) { frame_time_.count(secs); }
+	void countGameUpdate(double secs) { game_update_.count(secs); }
+	void countGameTick(double secs) { game_tick_.count(secs); }
+	void countGameDraw(double secs) { game_draw_.count(secs); }
+	void countGameUpdatesPerFrame(double count) { game_updates_per_frame_.count(count); }
+	void countRenderPresent(double secs) { render_present_.count(secs); }
+	void countMemoryUsage(double bytes) { memory_usage_.count(bytes); }
+
+private:
+	Counter frame_time_;
+	Counter game_update_;
+	Counter game_tick_;
+	Counter game_draw_;
+	Counter game_updates_per_frame_;
+	Counter render_present_;
+	Counter memory_usage_;
+};
+
+}

libswan/src/PerfCounter.cc

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+#include "PerfCounter.h"

libswan/test/PerfCounter.t.cc

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+#include "PerfCounter.h"
+
+#include "lib/test.h"
+
+test("")