Drawing a 3D box around a object based on hitbox

I want to draw a box that draws all around a object no matter the angle. I am using OBBMins and OBBMaxs to do this currently

I have the lines setup (aka the lines which make up the box), but currently they dont behave as expected, the corners of the box just go from the OBBMins to the OBBMaxs without covering the entire object.

Code (Is very long, so here it is in pastebin): http://pastebin.com/UUwaWyzW

And here are pictures: http://imgur.com/a/9XdIb

Any help please.