{HEAD ~ The sight lines} thus correspond to the wide static field of {TAIL ~ view} that is provided to the user 
{ HEAD ~ The sight lines } thus correspond to the wide static field of { TAIL ~ view } that is provided to the user
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH