const socket = io('localhost:3000'); const SIZE = 10; let coord = []; socket.on("connect", () => { console.log('Connected'); }); socket.on('data', (data) => { coord = data }); function setup() { createCanvas(800, 600); createButton('Save').position(0, 0).mousePressed( () => { socket.emit('save', coord); }); socket.emit('load', coord); } function draw() { background(0); fill(255); noStroke(); if (coord.length == 0) return; for (let {x,y} of coord){ ellipse(x, y, SIZE, SIZE); } } function mousePressed(){ coord.push ({x:mouseX, y:mouseY}); }