The Fountain Of Knowledge has been updated with a response to the following question on writing an engine with a quad-tree based world (landscape / terrain assumed):
I'm just getting into 3D graphics as a whole and I thought a good place to start
would be a world represented by a quad tree. I've read all the info I can find
on the Internet and set up the tree itself. The problem is that I can't figure
out a speed efficient routine that determines whether a particular square lies
(either completely or partially) inside the view triangle. All I've come up with
is a whole load of point-in-polygon tests and a mess of if statements and still
it doesn't work properly.
Am I missing something obvious? "