OPC opc; PImage dot; void setup() { size(640, 360); dot = loadImage("dot.png"); // Connect to the local instance of fcserver. You can change this line to connect to another computer's fcserver opc = new OPC(this, "127.0.0.1", 7890); // Map an 8x8 grid of LEDs to the center of the window, scaled to take up most of the space float spacing = height / 16.0; opc.ledGrid8x8(0, width/2, height/2, spacing, 0, true, false); // Put two more 8x8 grids to the left and to the right of that one. opc.ledGrid8x8(64, width/2 - spacing * 8, height/2, spacing, 0, true, false); opc.ledGrid8x8(128, width/2 + spacing * 8, height/2, spacing, 0, true, false); } void draw() { background(0); // Change the dot size as a function of time, to make it "throb" float dotSize = height * 0.6 * (1.0 + 0.2 * sin(millis() * 0.01)); // Draw it centered at the mouse location image(dot, mouseX - dotSize/2, mouseY - dotSize/2, dotSize, dotSize); }