title: Raycasting involving individual points in a Three.js PointCloud
body: <p>I have a <code>PointCloud</code> object that displays several points.  I'd like to be able to draw a bounding box around the clicked point.  Unfortunately, I can't seem to figure out how to access the individual point within the <code>PointCloud</code>, if this is even possible.</p>
  
  <p>This is the raycasting code I'm using...</p>
  
  <pre><code>window.addEventListener('dblclick', function (ev) {
      var mouse = { x: 1, y: 1 };
      mouse.x = ( event.clientX / window.innerWidth ) * 2 - 1;
      mouse.y = -( event.clientY / window.innerHeight ) * 2 + 1;
  
      var raycaster = new THREE.Raycaster();
  
      raycaster.params.PointCloud.threshold = 15;
      var vector = new THREE.Vector3(mouse.x, mouse.y, 0.5).unproject(camera);
      raycaster.ray.set(camera.position, vector.sub(camera.position).normalize());
      scene.updateMatrixWorld();
      var intersects = raycaster.intersectObject(particles);
  
      if (intersects.length &gt; 0) {
  
          console.log(intersects[0]);
          var hex  = 0x000000;
  
          var bbox = new THREE.BoundingBoxHelper(intersects[0], hex);
          bbox.update();
          scene.add( bbox );
  
      } else {
          // do nothing
      }
  }
  );
  </code></pre>
  
  <p>I can access the coordinates of the clicked point using <code>intersects[0].point.x</code>.  But passing <code>intersects[0]</code> to <code>BoxHelper</code> obviously doesn't work because <code>intersects[0]</code> is not an <code>Object3D</code>.  Likewise, if I use <code>intersects[0].object</code>, this draws a box around the entire <code>PointCloud</code>, whereas I'd like it just around the clicked point.</p>
  
  <p>Is this possible, and if so, how might I go about doing it?</p>
  
  <p>Thanks very much for any assistance!</p>