The computer generates custom pattern maps by altering {HEAD ~ the standard pattern maps} based upon {TAIL ~ the cloth cutting dimensions} 
based upon
The computer generates custom pattern maps by altering { HEAD ~ the standard pattern maps } based upon { TAIL ~ the cloth cutting dimensions }
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL