Details
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Bug
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Resolution: Unresolved
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P4: Low
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None
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4.7.1
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None
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HP tm2t-2100 running Win7 Pro,
Description
I'm developing a multi-touch app in Win7 using an HP tm2 (which supports 2 simultaneous touchpoints) and I'm seeing the following:
This sequence produces expected behavior:
-Start dragging finger 1: touchevents begin streaming.
-Start dragging finger 2: touchevents continue to stream, now with 2 touchpoints
-Release finger 2 while continuing to drag finger 1: touchevents stream with just the original touchpoint
-Release finger 1: touchevents stop.
But this does not:
-Start dragging finger 1: touchevents begin streaming.
-Start dragging finger 2: touchevents continue to stream, now with 2 touchpoints
-Release finger 1 while continuing to drag finger 2: all touchevents stop streaming. I get no touch releases when either finger is removed.
It seems that releasing the primary touchpoint prohibits updates from non-primary touches that are still in progress. This makes it hard to go from pan to pan+zoom by adding a second finger, then back to pan if the user releases the primary touch first.
I'm also seeing this in the Qt fingerpaint demo app... A quick test in the windows 7 Paint.exe has the secondary touch continuing to update as expected when the primary touch has been released or is stationary, which suggests that hardware and OS are functioning correctly.