title: Three.js MultiplyVector3 Deprecated How to replace
body: <p>I have a code, in three.js in console it says :</p>
  
  <blockquote>
    <p>DEPRECATED: Matrix4's .multiplyVector3() has been removed. Use vector.applyMatrix4( matrix ) or vector.applyProjection( matrix ) instead.</p>
  </blockquote>
  
  <p>But I have no idea how to do such.</p>
  
  <p>Here is my code:</p>
  
  <pre><code> var rotation_matrixc = new THREE.Matrix4();
   rotation_matrixc.extractRotation(CHROMEboyPC.matrix);
   var cam_vectorc = new THREE.Vector3(    100 ,  30 ,  5);
   var   final_cam_vectorc = rotation_matrixc.multiplyVector3(cam_vectorc);
   camera.position.copy(CHROMEboy.position ).add(final_cam_vectorc   );
   camera.lookAt(CHROMEboy.position);
  </code></pre>
  
  <p>How to write equivalent code using suggested Methods.</p>