Hi all, Im having a few problems trying to figure out how to test whether the nodes of my octree are visible/partially visible/not visible. (Im using D3D IM btw) At the moment, i simply use ComputeSphereVisibility to test this, but it''s not really accurate enough. What i need to do is to check using ComputeSphereVisibility for a rough "guesstimate" then actually check to see if the cube is Visible/Partially Visible/Not Visible. Ok so ComputeSphereVisibility is EASY to use, but i can''t figure out, using d3d, firstly how to obtain the points/planes for the viewing frustum, and secondly how to test the cube with these planes. Does anyone have some D3D Sample code, or a tutorial of some kind which demonstrates this (not just ones with endless algorithms, but with actual implementation samples). Thanks in advance Adam "Nutz" Hoult