History: -QueryPerformanceCounter

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The __QueryPerformanceCounter__ is the most precise time stamp counter on Windows systems. 

It's useful e.g. for ((-FPS|FPS)) calculations.


!!!Notes:

* The value of __QueryPerformanceFrequency__ never changes, while a system is running.
* Aware: It's possible that __QueryPerformanceFrequency__ returns 0 on some hardware systems.
* Aware: The difference between an older and a newer value of the __QueryPerformanceCounter__ can be negative. (This can happen when the thread moves from one CPU core to an other.)



!!See also:

* [http://msdn.microsoft.com/en-us/library/ee417693%28VS.85%29.aspx|Game Timing and Multicore Processors] - important notes
* [http://msdn.microsoft.com/en-us/library/ms644904(v=VS.85).aspx|QueryPerformanceCounter] - AP description
* [http://msdn.microsoft.com/en-us/library/ms644905%28VS.85%29.aspx|QueryPerformanceFrequency] - API description
* [http://en.wikipedia.org/wiki/Time_Stamp_Counter|Time Stamp Counter] - Wikipedia
* [http://support.microsoft.com/kb/172338|How To Use QueryPerformanceCounter to Time Code] - MSDN page with code snippets
* [http://msdn.microsoft.com/en-us/library/ee417693%28VS.85%29.aspx|High Precision Event Timer] (HPET) - Wikipedia, formerly ''Multimedia Timer''
* [http://support.microsoft.com/kb/274323|Performance counter value may unexpectedly leap forward] - MSDN
* [http://support.microsoft.com/kb/306979|How to use the QueryPerformanceCounter in Visual C#] - MSDN; Code snippet for use ((MOGRE|Mogre))