span>

  <span class="c1">// new position from mouse events</span>
  <span class="kd">function</span> <span class="nx">setPosition</span><span class="p">(</span><span class="nx">e</span><span class="p">)</span> <span class="p">{</span>
    <span class="nx">pos</span><span class="p">.</span><span class="nx">x</span> <span class="o">=</span> <span class="nx">e</span><span class="p">.</span><span class="nx">clientX</span><span class="p">;</span>
    <span class="nx">pos</span><span class="p">.</span><span clas