function setup() {

    createCanvas(windowWidth, windowHeight);  window.addEventListener("touchstart", function (event) { event.preventDefault(); }, { passive: false });

    window.addEventListener("touchmove", function (event) { event.preventDefault(); }, { passive: false });   document.addEventListener("gesturestart", function (e) {

    e.preventDefault();

    return false;

  });

}

function draw() {

    background(0);

    if (mouseIsPressed) {

        fill(255);

        ellipse(mouseX, mouseY, 50, 50);

    }

}