Hi, If i clip objects (multiple polys) to a full viewing volume (farZ/nearZ and four sides) I use the boundingbox of the object, min/max coords (8 in total), to find out wether its visible or not. Though some objects are obviously too big and will have all vertices outside the viewingvolume but is still visible because its polys intersect the frustrum. Any ideas how to fix this? /Fredrik

Perhaps you could use a bounding sphere for the visibility test?

Add a "center" point to you bounding box.... It''s only one more test.