From CCRMA Wiki
This instrument uses the slorkian fret-based mapping to trigger notes. It has been modified to allow polyphony.
How to Play
Pressing alphabetical keys triggers notes. Releasing them releases notes.
Moving the trackpad along the x-axis performs a filter sweep with a moderately high resonance.
Moving the trackpad along the y-axis detunes the sound's multiple oscillators from one another.
Pressing any of the digit keys 0-9 selects a different amplitude envelope. These envelope settings are arranged logically so that towards digit 1, sounds are more percussive, while towards digits 9 (and 0), sounds are pad-like.
Note that you may use a mouse rather than the trackpad to give the instrument a different feel. However, using the trackpad presents a nice advantage in that while your fingers are tied up holding many notes, you can still use your thumb to control the trackpad at the same time.
Here is the chuck file.