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Anu.Kh
21st July 2011, 12:17
Hello,

I am new to Qt programming.I have a QML application with animations during view transitions for which I want to measure FPS rate.
I am using QML_SHOW_FRAMERATE to get the time taken for each paint event.

Please let me know how I can get the actual framerate from the trace output.
I am currently doing this:-
Get average time for all these frames.
FPS = 1024/average time.

Output:-

Test case: Animation - flipforward
paintEvent: 24 time since last frame: 19
paintEvent: 1 time since last frame: 25
paintEvent: 2 time since last frame: 6
paintEvent: 3 time since last frame: 16
paintEvent: 3 time since last frame: 15
paintEvent: 3 time since last frame: 16
paintEvent: 3 time since last frame: 15
paintEvent: 2 time since last frame: 15
paintEvent: 3 time since last frame: 16
paintEvent: 2 time since last frame: 15
paintEvent: 3 time since last frame: 16
paintEvent: 2 time since last frame: 15
paintEvent: 3 time since last frame: 15
paintEvent: 2 time since last frame: 16
paintEvent: 3 time since last frame: 16
paintEvent: 2 time since last frame: 16
paintEvent: 20 time since last frame: 45
paintEvent: 2 time since last frame: 20
paintEvent: 2 time since last frame: 3
paintEvent: 3 time since last frame: 7
paintEvent: 4 time since last frame: 16
paintEvent: 3 time since last frame: 15
paintEvent: 3 time since last frame: 15
paintEvent: 3 time since last frame: 16
paintEvent: 3 time since last frame: 15
paintEvent: 3 time since last frame: 16
paintEvent: 4 time since last frame: 15
paintEvent: 4 time since last frame: 16
paintEvent: 4 time since last frame: 16
paintEvent: 3 time since last frame: 15
paintEvent: 6 time since last frame: 15
paintEvent: 3 time since last frame: 6
paintEvent: 2 time since last frame: 8
paintEvent: 4 time since last frame: 17
paintEvent: 3 time since last frame: 15
****************************************

Thanks and Regards,
Anu

stampede
21st July 2011, 12:20
FPS = 1024/average time.
If average time is time in mseconds spent on rendering frame, it should be more like FPS = 1000/average time.
Why did you put 1024 in there ?

Anu.Kh
21st July 2011, 12:30
I was wrong there..I will use FPS = 1000/average time.But is it the correct way to get the FPS?