[PATCH xf86-input-synaptics 1/2] Revert "Replace the motion estimator"

[Derek Foreman]

On 02/08/2012 08:42 AM, Peter Hutterer wrote:
> On Tue, Feb 07, 2012 at 01:07:07PM -0800, Chase Douglas wrote:
>> The algorithm is completely wrong because it uses subtraction of
>> unsigned variables. The negative effects of this commit manifest in
>> cursor warps to edges or corners of the screen.
>>
>> Since the algorithm has never worked right, previous testing must be
>> disregarded. Revert it until we have a tested algorithm.
>>
>> This reverts commit b26125e412a130b7a8f8b6adf9ffc8e9cc8df42c.
>>
>> Conflicts:
>>
>> 	src/synaptics.c
>>
>> Signed-off-by: Chase Douglas<chase.douglas at canonical.com>
>
> verified, tm is always garbage and so is t in the same hunk. Swapping the
> first to HIST_DELTA(0, i, millis) seems to do something (slowing down the
> cursor, mainly) but I didn't look into it further.
> Applied, commit is reverted, thanks.
>
>     141d912..49f6109  master ->  master
>
> Derek, any comments?

Somebody please hand me a brown paper bag.  :(

This patch was a cherry-pick from a larger body of work that made more 
invasive changes to the motion history stuff... it missed some fix-ups 
the later work provided.

All callers of HIST_DELTA() within regress() have their first two 
parameters reversed.  Additionally, the calculation of *dx and *dy have 
hw->millis and start_time reversed.


I'll submit a new patch after I'm confident that's the only thing missing.