Here is a pic of the patch gui I used in its current state:

Up and down in the arrays indicate "up=left" or "down=right" on the kit across 32 beats at a selected (metro) speed by the vslider.

And there are 8 drums up-down plus middle=noteoff. And each track (vertically of controls) is a different sample for that drum. (64 samples load into a 64 soundfile clones.

ex. -4 cymbal 1. -3 snare -2 tom1 -1 kick 0=noteoff 1 bass 2 tom2 3 hihat 4 cymbal2

The mixer knobs write the formula sort of like TOPsin(pit*MIDDLE)+BOTTOM. So moving from one drum l<->r as up<=->down.

p.s. the echo was added after the fact in Audacity.