[RFC] xserver: Masked valuators, DIDs, and ABS_MT_SLOT

[Peter Hutterer]

On Mon, Jul 05, 2010 at 09:15:42PM -0400, Chase Douglas wrote:
> On Tue, 2010-07-06 at 11:04 +1000, Peter Hutterer wrote:
> > On Thu, Jul 01, 2010 at 06:36:18PM -0400, Chase Douglas wrote:
> > >       Add extra functions for masked valuator input API
> > 
> > yes, but no :)
> > idea is right, implementation needs work. Please send this as a patch for
> > better comments. Most notably, you don't need GetPointerEventsM, just change GPE to take
> > the mask bits and fix up the callers in the DDXs.
> 
> I saw GPE is referenced in /usr/include/xorg/input.h, so I was afraid to
> modify its prototype. I certainly can change it though.

don't be. we don't really care about ABI guarantees across server revisions,
if a change makes sense add it. the only callers of GPE are the DDX's anyway
and they are in-tree. well, except VNC, they'll just have to live with it ;)

> <snip>
> > >       Add atom name for ABS_MT_SLOT properties
> > 
> > I'm not sure at all about this. I was hoping to abstract the slots so we
> > don't need to expose thos to the clients.
> 
> Given the approach that I have been taking, we have to expose the slot
> number to the clients. If you only send one touch data point per event,
> the client needs to know about its tracking data. The easiest way to do
> this is to just pass the ABS_MT_SLOT property from the kernel.

I thought the valuator number (or set of valuators) implicitly defined a
slot.

Cheers,
  Peter