nl_tokens: Finds the entry plane of the first octant that a ray travels through .
pl_tokens: function findEntryOctant ( tx0 , ty0 , tz0 , txm , tym , tzm ) { let entry = 0 ; // Find the entry plane. if ( tx0 > ty0 && tx0 > tz0 ) { // YZ-plane. if ( tym < tx0 ) { entry |= 2 ; } if ( tzm < tx0 ) { entry |= 1 ; } } else if ( ty0 > tz0 ) { // XZ-plane. if ( txm < ty0 ) { entry |= 4 ; } if ( tzm < ty0 ) { <mask> |= 1 ; } } else { // XY-plane. if ( txm < tz0 ) { entry |= 4 ; } if ( tym < tz0 ) { entry |= 2 ; } } return entry ; }