[H-GEN] synaptics pinching?

[Russell Stuart]

On Mon, 2010-11-15 at 13:17 +1000, Rod Hurford wrote:
> Have yet to get it ALL working but it seems promising. A lot of
> tweaking needs to be done using the synclient command line tool -
> which is good because changes can be undone if they don'tt work out.

I do have it all working, but this isn't multitouch.

One of the things the touchpad reports via an open source driver is "how
hard" you are pressing on the pad.  It is really just a measure of the
size of the area in contact with the pad.

If you use two fingers to touch the pad, the touch pad reports it as
just one big bloody fat finger.  But, that happens to be distinguishable
from 1 finger, the software can distinguish between you sweeping across
the pad with 1 finger and 2 fingers and so it can do different things.
Scrolling the area under the mouse say (ie 2 finger scroll) versus
moving the mouse if you use just one finger.

This is all well and good.  But it is not multitouch.  You need
multitouch to do something like pinch to zoom, because you need to sense
the position of two fingers and how they are changing relative to one
another.  From what I understand the hardware can do this and the
Windows drivers provided by Synatics can use it.  But Synatics hasn't
published the protocol and it hasn't been reverse engineered, and so on
Linux we are stuck with the fat finger kludge.