title: Three.js ray picking face segments of plane / mesh v69
body: <p>As quads faces are no longer supported in three.js. I am having trouble Raycast picking segments between 4 vertices points as a square as they are now made up of triangle faces. </p>
  
  <p>So my picking returns triangle shape not square:</p>
  
  <pre><code>                var faces = 10;
                  var myplane = new THREE.Mesh(
                  new THREE.PlaneGeometry(1000, 1000, faces, faces),
                  new THREE.MeshNormalMaterial({
                  color: 0x993333,
                  wireframe: false
                  }));
  
                  objects.push(myplane);
                  scene.add(myplane); 
  
                  //raycast code
  
  
                  if ( intersects.length &gt; 0 ) {
  
                      _controls.noRotate = true;
                      var face = intersects[0].face;
                      var temp = intersects[0].object;
                      var geo = temp.geometry;
  
                      geo.vertices[face.a].z -= 20;
                      geo.vertices[face.b].z -= 20;
                      geo.vertices[face.c].z -= 20;
                      //want other face verts below basically
                      geo.vertices[face.d].z -= 20;
                      geo.vertices[face.e].z -= 20;
                      geo.vertices[face.f].z -= 20;   
                      geo.verticesNeedUpdate = true;
  
                      if(intersects[ 0 ].faceIndex % 2 == 0){
                          // geo.vertices[intersects[0].faceIndex + 1].z = 40;     
                         // console.log("Even face Index: " + intersects[ 0 ].faceIndex);
  
                       }else{
                          // console.log("Odd face Index: " + intersects[ 0 ].faceIndex -1);
                         //geo.vertices[intersects[0].faceIndex - 1].z = 40, of course doest work
                       }
  
                      }   
  </code></pre>
  
  <p>Below is a 2d example for a better vsual...
  Currently I get the red out-come , but I'm wanting to pick like the green example:</p>
  
  <p><img src="https://i.stack.imgur.com/xGnGx.jpg" alt="example of plane segments"> </p>