Comment 14 for bug 381884

That is great! I'm on an old 2-1 macbook (2006). This is good news as it
means that the functionality I am wanting exists in the driver but is not
being executed for my trackpad. The driver currently branches depending on
what kind of trackpad it detects (different versions for different
powerbooks, ibooks, macbooks, etc), and it appears that your Macbook Pro 5,1
branch has the bugs worked out.

The only other issue I could ask for a test of is this:
1) Put your finger in the middle-top of the touchpad with very light
pressure (as little surface contact as possible)
2) Slowly move finger down towards bottom of the pad

With my hardardware and driver, I can watch my cursor "jump" to every inch
or so on my screen in a very non-smooth fashion. This is because my driver
is not appropriately weighting the inputs from each of my 16 touchpad
sensors. I hope that makes sense. I only noticed it when trying my wife's
macbook pro (running OS X) and being amazed at how smooth, sensitive, and
non-frustrating the trackpad experience was.

Blaine

2010/4/13 Νίκος Αλεξανδρής <email address hidden>

> @Blaine:
>
> Here some facts (tested on firefox, konqueror, dolphin in my Kubuntu
> box):
>
> + no jumping cursor at all
> - indeed sometimes scrolling in dolphin and konqueror feels a bit fast (but
> it only starts scrolling when I want it)
> -/+ in firefox I have "smooth scrolling" enabled and is fine
> + rolling finger is precise and feels smooth here
>
> Regards, Nikos
>
> --
> Appletouch touchpad driver produces jumpy two-fingered scrolling
> https://bugs.launchpad.net/bugs/381884
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in The Linux Kernel: New
> Status in Mactel Support: New
> Status in "xserver-xorg-input-synaptics" package in Ubuntu: Confirmed
>
> Bug description:
> Binary package hint: xserver-xorg-input-synaptics
>
> My system is: Linux richard-laptop 2.6.28-11-generic #42-Ubuntu SMP Fri Apr
> 17 01:58:03 UTC 2009 x86_64 GNU/Linux. However, this issue applies to at
> least Intrepid and Jaunty, 32 and 64 bit, running on Apple Mac hardware that
> uses an Appletouch touchpad. It has also been reported in the Gentoo and
> Debian forums.
>
> >From what I can find on the Net, the Appletouch touchpad was first used in
> February 2005 for the G4 aluminium PowerBook, and last used for the Macbook
> Pro in its 3rd generation, then 4th generation Intel Macbook in early 2008.
>
> The issue is with two-fingered scrolling. The Appletouch features the
> ability to detect two (or three) touches. OS X uses this feature to enable
> scrolling, similar to a scrollwheel on a mouse.
>
> The synaptics driver causes the simulated scrollwheel to start moving as
> soon as one places a second finger on the touchpad. That is to say, placing
> a second finger causes the trackpad driver to deliver scrolling signals,
> which means that attempts at vertical scrolling feels jumpy, or over
> sensitive.
>
> There was an update to the OS X driver that fixed this situation for Apple.
> I guess that it detects the second finger and programmatically ignores the
> first few scrollticks, thereby 'deadening' the output. This is what we
> need.
>
> The synaptics driver allows for some modification, but not for multitouch
> input. This needs to be fixed at source code level.
>
> Richard
>
> To unsubscribe from this bug, go to:
> https://bugs.launchpad.net/linux/+bug/381884/+subscribe
>