Update PlayCanvas screenshot and description.

chrome/common/extensions/docs/templates/articles/game_engines.html

 <h1>Game Engines</h1>
 
 
 <p>
 Several graphically intense interactive application frameworks / game engines
 exist that target web technologies. The following are some we recommend with
 instructions for producing a Chrome App.
 </p>
 
 
 <h2 id="playcanvas">PlayCanvas</h2>
 <p>
 <a href="https://playcanvas.com/">https://playcanvas.com/</a>
 </p>
 
 <p>
 PlayCanvas demo on Chrome Web Store:
 <a href="https://chrome.google.com/webstore/detail/swooop/jblimahfbhdcengjfbdpdngcfcghladf?hl=en-US">Swooop</a>
-<img src="{{static}}/images/swooop.png"
-     width="460"
-     height="340"
-     alt="Promotional image for Swoop demo showing a biplane.">
+<a href="{{static}}/images/playcanvas_designer2.png">
+  <img src="{{static}}/images/playcanvas_designer2_500_335.png"
+    width="500"
+    height="335"
+    alt="PlayCanvas editor screenshot.">
+  </a>
 </p>
 
 <p>
-"PlayCanvas is a visual development platform for 3D web content. Both the
-tools and the web apps you build are powered by HTML5. The entire software
-platform is web hosted so there's nothing to install and you can access your
-work from any device that runs one of the supported web browsers." - <a
-href="http://developer.playcanvas.com/user-manual/introduction/">PlayCanvas
-User Manual</a>
+PlayCanvas a free and open source WebGL Game Engine targeting mobile and
+desktop. Its browser based development tools support real-time collaboration.
 </p>
 
 <p>
 PlayCanvas exports content that requires a small amount of manual work to
-package into a Chrome App. See: 
+package into a Chrome App. See:
 <a href="http://developer.playcanvas.com/user-manual/publishing/chromewebstore/"
 >PlayCanvas Packaged App Publishing Documentation</a>.
 </p>