August 17, 2014, 11:56:06 am
You don't need to do anything.
Spotlights will automatically get clipped to the surfaces they shine on when its rendered.
That process is too expensive for real-time for Build Mode, although you can see it, if you use Build With Effects and GI Preview GI and Shadows turned On.
Note: Fill or Omni Lights will not get clipped.