You could take a look here, it''s the best tutorial i ever found.
http://www.markmorley.com/opengl/frustumculling.html




www.web-discovery.net

GameTutorials has a frustum culling program in C++, which I've converted to Delphi. Grab it over here (120K).

You need the DirectX headers (not included) as I'm using DirectInput 8 for handling the keyboard and mouse. You can get the headers from http://www.crazyentertainment.net/ (the site's down at the mo, but it should be back up soon), assuming you don't have them already.

I may have stripped out some of the comments in the process of converting, so it might be an idea to check the original C++ code if you want more comments (not sure, though). Also, caveat emptor: the conversion was done quickly so there may be a bug or two lurking about.

Hit the 'f' key to see the effect that frustum culling has (which can be big). You can move around with wasd and the mouse.

EDIT: The two files you're interested in are "frustum.pas" and "PlayingGameState.pas", btw . The rest is just a quick framework. Also, note that you'll need to extract the files before running - the code wants to load a .raw texture (which is not used and is just totally black) because I didn't remember to change the texture manager code. Doh!

[edited by - Alimonster on August 31, 2002 9:41:53 PM]

Sorry to bother you, but it might be worth your while downloading the zip again. I''ve added more comments to the functions so that the rest of the stuff makes a little more sense .