I have frustum so I render what is in the FOV. But I don''t want to render faces that are behind an object (within the fov). What should I look for to figure this out? and is culling used to tell directx not to render faces that are pointing away from me?

Well....

Your first problem has various solutions. Normally people would tell you to look out for quadtree or octree or BSP tree culling, or even some portal tech talk but I''ll point you to oclussion culling, you can find a good article in gamasutra:

http://gamasutra.com/features/20020717/bacik_01.htm

Either ways all the other forms are widely used and you can certainly find articles here or in Gamasutra or at Flipcode or at any decent gameprogramming site. Basically, if you want to do indoor scenes, then all the previous cases work very well and some might work better in some cases but they all do their job. BUUTTT, if you want to do outdoor scenes, with vast landscapes, then forget them and look at occlusion culling which is very easy to do, if you adapt it a bit you could even use it for indoor scenes.

As for the last bit, you''re thinking of backface culling, and that''s what it exactly does, it takes in consideration the winding order (if it''s clock-wise or counter clock-wise) and determines if the face is facing the person to see if it needs to be rendered(ofcourse if you''ve got something like a peice of paper or some thin material then you need to create a second face or switch off backface culling to render the the other side), it''s all in the DX docs. Another reason to switch off BF culling (and switching on wireframe rendering) is for debugging possible errors.

Thanks for a good explanation!