title: Three.js: move object along face normal direction
body: <p>I stucked a bit.</p>
  
  <p>I have a face, its center position and the face normal. I want to place another object in front of that face along the normal direction, lets say a 1 unit far. The object I want to place in front of the face, isn't rotated properly yet, thats actually another task to solve: rotate the object (plane) perpendicular to the normal of the face. Any hints for me?</p>