i’m trying to write some kind of 3dengine and i’ve got trouble with generating viewing cone.
i want to use gluLookAt() to place observer somewhere and want to determine which polygons should be sent to gl. i could use gluProject to generate left, right, top and bottom clipping planes but i also want far and near planes (z-coordinate is strange after gluProject so it cannot be used in this way)
i’m just seeking for some useful math or trick… heeeelp, i’m lost…