title: keyPressed() does not activate in p5
body: <p>I am trying to spawn a lightsource in my 3D-space using keyPressed(). However, upon pressing keys on the keyboard, nothing happens. I did as instructed in this following tutorial, and can't see what's the difference with his and my code: <a href="https://www.youtube.com/watch?v=UvSjtiW-RH8" rel="nofollow noreferrer">https://www.youtube.com/watch?v=UvSjtiW-RH8</a></p>
  
  <p>I have tried to look for differences between the tutorial and my program, and I have tried to use something else than a light source as the object/event to be activated with keyPressed() (for example I tried changing the background color).</p>
  
  <pre><code>function setup() {
      createCanvas(windowWidth, windowHeight, WEBGL);
  }
  
  function draw() {
      background(100);
  
      push();
      ambientMaterial(255, 255, 255);
      rotateY(angle);
      rotateX(angle);
      sphere(300);
      translate(200, 300);
      sphere(50);
      pop();
  }
  
  function keyPressed() {
      pointLight(255, 55, 255, 10, 200, 400);
  }
  </code></pre>
  
  <p>I expected to see the light upon pressing a key on my keyboard, but this does not happen. No error messages are shown.</p>