title: Moving the camera, lookAt and rotations in three.js
body: <p>I'm having trouble understanding lookAt and the rotations of the camera.</p>
  
  <p>I have a circle of small spheres around [0,0,0] on the x-y plane.</p>
  
  <p>The camera is placed at [0,0,30] and after a lookAt the rotation of the camera is [0,0,0]. The circle appears as if looking from above (as expected).</p>
  
  <p>Then I move the camera to [30,0,0] and after a lookAt the rotation of the camera is [0,90deg,0]. The circle appears on its side, but vertically, not horizontally as I would expect. Why is the camera rotated by 90 degrees for y?</p>
  
  <p>After that I move the camera to [0,30,0] and after a lookAt the rotation of the camera is [-90deg,0,90deg]. The circle again appears on its side, vertically, not horizontally.</p>
  
  <p>Why is the camera rotating? I thought that there would be no rotation at all since it was on the x and y axes themselves.</p>
  
  <p>Thank you for any help! :-)</p>
  
  <p>Note:  Originally posted at <a href="https://github.com/mrdoob/three.js/issues/2917" rel="noreferrer">https://github.com/mrdoob/three.js/issues/2917</a> but was told to come to Stack Overflow.</p>