Oct Tree
File id	$00	12	File id
Level id	$04	17	Level id
OTIT-link	$08	12	Link to the Oct Tree Interior Node Array
OTLF-link	$0C	12	Link to the Oct Tree Leaf Node Array
QTNA-link	$10	12	Link to the Quad Tree Node Array
IDXA-link	$14	12	Link to the Index Array
IDXA-link	$18	12	Link to the Index Array
Not used	$1C	1004	Not used
