Xorg input thread (2)

Keith Packard keithp at keithp.com
Sat Jul 7 11:48:52 PDT 2007


On Sat, 2007-07-07 at 11:11 +0300, Daniel Stone wrote:
> On Fri, Jul 06, 2007 at 10:45:39PM -0700, Keith Packard wrote:
> > Ultrix systems placed the entire input subsystem in the kernel,
> > connecting the mouse hardware directly to the cursor position update
> > function.
> 
> 'Entire input subsystem' is a no-go, obviously.  Particularly if we're
> going to actually use this input transformation stuff ...

By "entire input sybsystem", I mean only up to the point of creating a
root window coordinate. That's before input transformation. Effectively,
the portion of the server currently running from the signal handler
would run in the DRM instead. We can look at the old Ultrix code to see
how that worked, it wasn't that complicated iirc. Transforming the
relative mouse motion into an absolute screen position isn't that
complicated, but it does involve acceleration and cursor limits. Much of
the existing server input architecture is structured to handle precisely
this separation of responsibilities.

-- 
keith.packard at intel.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 189 bytes
Desc: This is a digitally signed message part
URL: <http://lists.x.org/archives/xorg/attachments/20070707/48450794/attachment.pgp>


More information about the xorg mailing list