[ANNOUNCE] xf86-input-evdev

Peter Hutterer peter.hutterer at who-t.net
Mon Oct 27 01:05:03 PDT 2008

On Mon, Oct 27, 2008 at 08:44:24AM +0100, Søren Hauberg wrote:
> Just a quick thought: double-scaling means we transform one coordinate
> from [a, b] to [c, d] in the driver, and then from [c, d] to [e, f] in
> the server, right? Here [a, b] is determined by the hardware. What if
> we choose [c, d] equal to [e, f] ? Then the scaling in the server
> would be from [e, f] to [e, f] i.e. a unit scaling, which I assume
> doesn't affect the precision (if it does, then we could let the server
> check if the scaling is a unit-scaling, and only perform the actual
> scaling if it is not).

uhm. we seem to be coming back round in a full circle here.
As I said in an earlier email, we don't need scaling in the driver if you can
specify the min/max range at startup. So in your example, you only need
scaling in the driver if you want to change [c, d] at runtime. If you can just
set it up to [e, f], then you can just skip the scaling altogether.

Our problem is that we don't konw [a, b] at server startup, isn't it?


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