Re: [Qemu-devel] paravirtual mouse/tablet

[Gerd Hoffmann <kraxel@redhat.com>]

>> There are three cases:
>>
>> (1) no pressure supported (i.e. your mouse moving around in the vnc
>> window and qemu reporting this as tablet coordinates).
>> (2) just pen/finger present/not present supported.  pressure jumps
>> between 0 and max (and we can make max == 1 in that case).
>
> Phew - that's one of the bits where touchpads and tablets behave
> differently IIUC. For touchpads, pressing means movement happens.
> For tablets, pressing means an actual press, as if you would press
> your pencil on a sheet of paper. So for tablets, pressure==1
> basically means click.

I wouldn't make a difference from the virtual hardware perspective.  If 
something touches the pad/tablet surface we'll report the position where 
it happened (and the pressure if supported).  Whenever this is 
interpreted as click or not is up to the guest.

> Now the thing is that multitouch gestures might take non-click
> pressure into account for their calculations. So we need pressure
> for movements on touchpads, but with tablets, we only need pressure
> when clicks happen. For everyone else, clicks would just be a button
> press.

-EPARSE.  What is "non-click pressure" ?

cheers,
   Gerd