Static loop 

pub static loop: RLoopInternalType

By default, p5.js loops through draw() continuously, executing the code within it. However, the draw() loop may be stopped by calling noLoop(). In that case, the draw() loop can be resumed with loop().

Avoid calling loop() from inside setup().

Use isLooping() to check current state of loop().

Examples

let x = 0;
function setup() {
  createCanvas(100, 100);
  noLoop();
}

function draw() {
  background(204);
  x = x + 0.1;
  if (x > width) {
    x = 0;
  }
  line(x, 0, x, height);
}

function mousePressed() {
  loop();
}

function mouseReleased() {
  noLoop();
}