title: When BACK faces are drawn, are their normals automatically reversed?
body: <p>I am drawing only back faces of a geometry by invoking <code>gl.cullFace(gl.FRONT)</code>. I noticed that the shade of light on these surfaces is opposite to what I expect. For correct rendering, do I have to explicitly reverse the direction of surface normals on back faces, or does the OpenGL subsystem automatically do that?</p>
  
  <p>EDIT: Coming to think of it, if I reverse their normals manually they will become front faces and will be culled.</p>