Your LED is 144*9 LEDS? Before starting to patch anything ‘cool’ you want to spend sometime on making a little simulation.
That way you can patch the cool stuff without having access to the LED screen.
2 ways to make content for LEDs, make something cool in a renderer and use a Pipet to collect the colors. Or patch it directly.
For your specific question, I would use Gridpick.
GridpickCirc.v4p (10.1 kB)