[LAU] Touchpad to MIDI

[Peter P.]

Hi Will,

as others have said this is very easy with a Pd patch. Use Pd from here,
preferably over other distributions:
http://msp.ucsd.edu/software.html

Install the [hid] external using the "Find externals..." menu entry.
Write a patch that loads this external library into pd, for example by
creating an object
 [declare -lib hid]

More help at the Pd mailing list at
https://lists.puredata.info/pipermail/pd-list//

Eventually you will have to change the permissions on the
/dev/input/deviceXX file to have Pd read from it directly.

Oh, I found it handy to disable the pointing device I am querying in Pd
in the xserver so I don't click somewhere by accident and can still use
another mouse to point and click:

List all X input devices
        xinput --list
filter for numeric ID of "USB Optical Mouse"
        xinput --list | grep "USB Optical Mouse" | cut -d "=" -f 2 | cut -f 1
get the number for the "Device Enabled" parameter of that mouse
        xinput --list-props `xinput --list | grep "USB Optical Mouse" | cut -d "=" -f 2 | cut -f 1`
which in my case was 164. Then change its value to 0 or back to 1
        xinput --set-prop `xinput --list | grep "USB Optical Mouse" | cut -d "=" -f 2 | cut -f 1` 164 0
        xinput --set-prop `xinput --list | grep "USB Optical Mouse" | cut -d "=" -f 2 | cut -f 1` 164 1

best, P