title: Create a canvas with rounded corners in p5.js
body: <p>I can't seem to find any information on the p5.js reference page as to how to round the corners on a canvas created through createCanvas(). This is possible with rectangles, as the fifth input the function takes is the border radius. This is not the case when creating a canvas. </p>
  
  <p>I've put together a little example demonstrating a flat-cornered canvas with a curved-cornered rectangle inside, what I am aiming to reflect in the canvas' shape.</p>
  
  <p>Any help would be appreciated. Thanks.</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>function setup() {
    createCanvas(200,200);
  }
  
  function draw() {
    background(32);
    rectangle();
  }
  
  function rectangle() {
    stroke(255);
    fill(255,255,255,100);
    rect(70,70,60,60,10);
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;head&gt;
    &lt;script src="//cdnjs.cloudflare.com/ajax/libs/p5.js/0.5.10/p5.js"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
  &lt;/body&gt;</code></pre>
  </div>
  </div>
  </p>