   Premature Culling
  I've just implemented Frustum Culling in my 'engine'.Everything's fine, except that objects disappear just before they are fully off screen.I guessing that it might be because the models I'm using - tiger.x from the SDK - has a different origin to the centre of its bounding sphere.If so I'd need to shift the position I pass to the culling routine by the difference between the origin and the centre?   
  You need to shift the position of your bounding sphere so that it bounds your object. If the object isn't completely inside, then the sphere is not a bounding sphere and must be moved or enlarged (or both).   ;  I've solved that problem (was taking the address of now deleted temporary variables)Now it seems reluctant to cull, rendering objects even when they're completely off screen (have an onscreen tally of the number of objects rendered).Is this behaviour that expected?[EDIT] I guess even if the object isn't visible, part of its bounding sphere may be.[Edited by - DerekBaker on July 24, 2006 5:02:31 PM];Quote:Original post by DerekBakerIs this behaviour that expected?[EDIT] I guess even if the object isn't visible, part of its bounding sphere may be.I suggest that you create a test case: place manually the spheres and camera, and determine if the right number of objects are culled. ;Quote:[EDIT] I guess even if the object isn't visible, part of its bounding sphere may be.A good trick is to actually render the bounding sphere of your objects, that way you can see if this is what is causing the problem.  IMO sounds like either an incorrect bounding sphere, or a correct bounding sphere that doesn't fit the object very well.   ;  The model is several times longer than it is high, so there's going to be a lot of empty space in the sphere.;  You could scale the bounding sphere by a 3d vector to match the general dimensions of the object.   ;  Or perhaps use a cylinder as bounding geometry   