[linux-audio-dev] Knobs, the reply

[Dave Robillard]

On Mon, 2004-06-14 at 12:20, Lance Blisters wrote:
> On Thu, Jun 10, 2004 at 08:42:42PM -0400, Dave Robillard wrote:
> > Speaking of touchpads, does anyone know of a (usb) touchpad that works
> > with your finger, not just a pen?  (The only ones I've seen just work
> > with the stylus, which is no good)
> > 
> > I want to get one and set it up as a MIDI controller, like a poor mans
> > Kaoss Pad (and what I think would be the ultimate expressive MIDI
> > controller).
> > 
> > Surely one of these things must exist?
> 
>   Most (all?) by default work only in relative motion mode, 
> not absolute motion mode.  So moving your finger a bit to the left
> sends -5 -7 -2  but you have no idea of where on the pad your
> finger is.  In fact, the relative events don't even add up; move
> back and forth a from side to side a dozen times, the values tend
> do drift in some direction (the direct USB events, pre-mouse
> accelleration)  So, it doesn't map onto the kaoss pad very well.
> I have an "easy-cat" usb touchpad.  IIRC it has an absolute mode
> under windows, but i've seen no linux code to enable it.  They
> wanted me to sign an NDA for futher info.  However, this device
> is still usable for x-y parameter control, just only via relative
> motions.  There are some binding files to support this device in
> GDAM's CVS repository.
> 
>   -geoff

Now that I think of it, with a small touchpad, relative would be okay
anyway.  Not accurate enough for absolute to be that useful.

Absolute would be better, for sure, but relative would be okay - I
personally just want to be able to drag my finger around and manipulate
things in an expressive way.

-DR-