Marcus Barnes (marcus++at++multigen.com)
Mon, 6 Apr 1998 16:59:32 -0700
[chuckle]
>The vertical line is the vertical retrace. When the
>draw ends it swaps and the image is switched at the next vertical
>retrace, in the diagram this is the line at the end of draw. Almost
immediately
>thereafter the video starts getting sent on the wire without any video
>buffering and should begin to appear on your screen if you use CRTs.
Raster refresh takes a full video field (interlaced) or frame (noninterlaced).
The scan out is a sequential operation after all. On a 60Hz noninterlaced
monitor (most common these days) that means an additional 16.67 ms. of latency
before the man in the loop sees the update caused by his sitck input.
>There are different schools of thought on where latency should be
>measured to. Some say the beginning of video, others say the end
>but it has little to do with the I.G. You say potato I say potato.
Latency includes the period of time between a control input and the resulting
feedback. In this case, feedback means a visable update of the display. You can
choose to ignore video refesh, and input sampling latency for that matter, when
calculating your end to end latency ... if it like. Just keep some motion
sickness bags handy ;)
Regards.
--
+ Marcus Barnes, Technical Staff mailto:marcus++at++multigen.com +
+ Multigen Inc. http://www.multigen.com +
+ 550 S. Winchester Blvd. phoneto:1-408-556-2654 +
+ Suite 500 San Jose CA 95128 faxto:1-408-261-4102 +
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