>>105304766Perspective is just an abstraction of real life, so it really just depends on what you're drawing, and from what angle. If you look at a box right from the front, then the vanishing point should be on the horizon , right in front of you. You turn the box around, the vanishing point shifts on the horizon. But if you then tilt the box, the vanishing point moves up from the horizon. Long way of saying it depends, but learning to visualize this in 3D helped me grasp perspective properly.
The simple answer then is to just put the vanishing point where it feels right. Alternatively, if you want an object to be more specifically angled and placed, you can rough sketch the object, then reverse engineer the vanishing point from there.
