title: Find arc() edge while using p5js
body: <p>I can't understand how i can find arc() edge.
  Currently i control White line with mouse.
  And goal is to change that line to Red, if mouse is outside Yellow zone.</p>
  
  <p>I use this code:</p>
  
  <pre><code>arc( xloc, yloc, size - i * steps, size - i * steps, 60, 90 );
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/OVZuu.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OVZuu.png" alt="enter image description here"></a></p>