Le 9 mars 10 à 23:29, Henrik Rydberg a écrit :

Stéphane Chatty wrote:

quoted

Le 9 mars 10 à 22:59, Henrik Rydberg a écrit :

quoted

On the contrary, the MT protocol is dependent on one of the
single-touch events
BTN_TOUCH or ABS_PRESSURE to be present in the event stream for  
proper
device
identification and for correct handling of zero-finger events.  
The latter
because at least one value (BTN_TOUCH or ABS_PRESSURE) must change
state to pass
through input filtering when no fingers are present. This is what  
needs
clarification.

Someone has pointed this to me a few weeks ago and tbh I had the  
feeling
that this is a bug in the protocol that we failed to notice last  
summer.
I agree with you that BTN_TOUCH plugs the hole, but I don't find  
it very
satisfactory that we need one protocol to inform another.

Frankly, I never even imagined there would be pure MT devices  
without support
for the existing single-touch applications. But sure, it was an  
oversight at the
time.

In my case, not detecting it was a pure mistake, nothing else :-) And  
I've worked with formal models of input devices for decades, which  
makes it really embarrassing.

St.

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