Re: Stats Question correction

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Marcus Barnes (marcus++at++multigen.com)
Mon, 6 Apr 1998 12:55:04 -0700

On Apr 6, 11:46am, Jay Gischer wrote:
>The label "frame" appears to be causing a great deal of confusion
>here. Recall the picture of Performer's pipe
>
>APP | Frame 1 | Frame 2 | Frame 3 | Frame 4 | etc
>
>CULL | | Frame 1 | Frame 2 | Frame 3 | etc
>
>DRAW | | | Frame 1 | Frame 2 | etc
>
>If 30.0 Hz is the target frame rate then the target from one pipe
>stage boundary to the next is 33.3 ms.
>
>However, the time reported with the label "frame" is a latency time,
>and measures the time from when the frame starts the APP stage, to
>when it completes the draw stage. Ignoring special cases, this time
>is 3 times as long as the time for a single stage. Three time 33.3 is
>100, so 96.3 is about right.

I don't believe that this timeline takes the video refresh period into account.
Recall that the draw is double buffered. Therefore you don't actually see the
results of the draw process for another "video frame". This adds to your
latency.

Regards.

--
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