title: Lasso tool in sigmajs
body: <p>Is it possible to create lasso tool on sigmaJS 1.2.1 version? HTML canvas is able to draw on it, but when convert div to canvas, sigmaJS is not able to load the nodes and edges. How can I integrate sigmaJS to load in a canvas?</p>
  <pre><code>&lt;div id=&quot;container&quot;&gt;
    &lt;style&gt;
      #graph-container {
        top: 0;
        bottom: 0;
        left: 0;
        right: 0;
        position: absolute;
      }
    &lt;/style&gt;
    &lt;div id=&quot;graph-container&quot;&gt;&lt;/div&gt; &lt;!--I changed here to use canvas, but not able to load--&gt;
  &lt;/div&gt;
  
  &lt;script&gt;
      var i,
          s,
          N = 100,
          E = 500,
          g = {
            nodes: [],
            edges: []
          };
  
      // Generate a random graph:
      for (i = 0; i &lt; N; i++)
        g.nodes.push({
          id: 'n' + i,
          label: 'Node ' + i,
          x: Math.random(),
          y: Math.random(),
          size: Math.random(),
          color: '#666'
        });
  
      for (i = 0; i &lt; E; i++)
        g.edges.push({
          id: 'e' + i,
          source: 'n' + (Math.random() * N | 0),
          target: 'n' + (Math.random() * N | 0),
          size: Math.random(),
          color: '#ccc'
        });
  
      // Instantiate sigma:
      s = new sigma({
        graph: g,
        renderer: {
            container: document.getElementById('graph-container'),
            type: 'canvas'
          }
      });
  &lt;/script&gt;
  </code></pre>
  <p>How can I make the graph-container a canvas for drawing and also load the nodes and edges? or is there any other ways to have drawing tools and also sigmajs nodes &amp; edges. Please advise. thank you.</p>