On subsequently rendering, the point samples are modified continuously according to {TAIL ~ an updating} of {HEAD ~ the 3D primary video data} 
On subsequently rendering , the point samples are modified continuously according to { TAIL ~ an updating } of { HEAD ~ the 3D primary video data }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD