title: Three.LinePieces with different materials (colors)?
body: <p>I was trying to draw a dense graph with more than 10k edges using three.js.</p>
  
  <p>LinePieces was used for better performance but I could not figure out how to specify different colors for each edge (Line) since only one "material" could be used to create the Line object.</p>
  
  <p>Here's some of the code:</p>
  
  <pre><code>function drawEdges() {
      edgeGeometry = new THREE.Geometry();
      edgeMaterial = new THREE.LineBasicMaterial({ opacity: 0.1 });
          foreach source-target node pair:
              edgeGeometry.vertices.push(new THREE.Vector3(source.x, source.y));
              edgeGeometry.vertices.push(new THREE.Vector3(target.x, target.y));
      }
      var edges = new THREE.Line(edgeGeometry, edgeMaterial, THREE.LinePieces);
      scene.add(edges);
  }
  </code></pre>
  
  <p>My question is: Is it possible to use different materials if using THREE.LinePieces? Any hint is appreciated.</p>
  
  <p>Thanks in advance.</p>