You're mixing up two concepts. An entity always has a bounding box - regardless of the POLYGON flag. This bounding box is determined by the min_x ... max_z members. The POLYGON flag just tells the engine to ignore the bounding box when doing collision detection, but does not remove it. Setting d3d_lines to a value > 1 (This is exactly what happens when you press F11 twice) will draw the bounding box regardless of the polygon flag.

At a first glance you might think that this is irritating and senseless but you can use the bounding box for other purposes as well, e.g. to emit particles inside a predefined cube etc. Even entities with the PASSABLE flag set can use their bounding boxes.


Always learn from history, to be sure you make the same mistakes again...