For reasons too long and boring to go into, I've got a couple of Page Types / ClassNames that I would like NOT to show in the Site Tree hierarchy in the CMS. Where in the core code can I place this logic? Basically I have a relation between two page types such that each relation that is made from within those two respective page types creates a page instance of the relational page type in the CMS interface (two $has_many's and a $has_one with two entries on the other side). This is obviously not desirable. Can anyone help me find the right place to include this code?
Contrary to my intuition, /cms/code/CMSSiteTreeFilter.php did not seem to be the right place to do it.