   Frustum Culling problem.
  Hey does any have any experience with frustum culling where it culls ok in one view direction and on the other view direction it doesn''t? ie. it only culls 180 degrees one a certain view direction.Thanks for any replies.  
  isnt frustum culling culling everything which is not in the frustum ?? why would it only cull a certain direction. ?    Its my duty, to please that booty ! - John Shaft  ;  That''s what I''m trying to find out.;  You use frustum culling to find out, which objects, polygones you only must redner, wich of them are in the actually view. So you dont need to do this in the background. Read some stuff about this topic.  ;  ok... is there anything that opengl needs for the model and the  projection matrices for the frustum to be extracted properly?i''ve read mark morley''s tutorial on this and im pretty sure that my code is similar to his. i thought that if i leave some opengl commands out during drawing that the frustum extraction is incorrect. it seems as though its rendering the opposite ie. all the stuff that is outside the frustum for a particular view.austrian coder: i dont need to do this in the background? what exactly do u mean by this? i have an octree and bounding boxes in the leaves that i check against the frustum. i do this once for each loop in the program.what else should i read?  ;  if you are generating the frustum correctly then it should work no matter what direction you''re facing.to generate the frustum you''ll need:the view direction and orientation the far and near clipping plane distancesEITHER the width and height of the near plane    OR the field of view (same thing, can be converted to width/height using simple trig)the first one can be got from the veiw matrixthe second two can be got from the projection matrixfrom this you can generate the frustum as a set of planes.have a look at how the matrices are generated - if you''re still stuck reply back and I''ll elaborate more.TobyGobsmacked - by Toby Murray;  Just as another note - should frustrum culling not be done BEFORE OpenGL gets a look at anything? Fast culling of complete objects outside of the view frustrum is IMHO the only way to get real speed. If you rely on OpenGLtodo the culling, you are still handling WAY too much data which you would not need to process. RegardsThomas TomiczekTHONA Consulting Ltd.(Microsoft MVP C#/.NET)  ;  Yeah. In each frame you need to get the frustum planes immediately after defining your view matrix, or at least before altering it with subsequent calls (and definitely not before defining the view!). For OpenGL it looks like:glClear(...);glLoadIdentity();gluLookAt(...);extractFrustum();;  zppz: cool, thats what im doing now.its fixed now so i guess cased closed  a bit of a hack tho.thanks all.last thing. i have matrix that is float[4][4] in an object, is it safe to reinterpret_cast to this from float[16] assuming that the rows and columns are aligned for this?[edited by - -=code=- on August 20, 2002 5:33:44 AM];  they are two very different thiings.  matrix[4][4] is an array of 4 arrays each containing 4 elements.  I dont think you can cast from one to other.  