if you stand in the middle of a sidewalk and look down it will get smaller and so the vanishing point should be in the middle of the side walk. But if you stand a little bit to the right where will the vanishing point be (in this case i want the vanishing point to change and not the person's viewing position)?
and how far do you put the two vanishing points? will it always be on the edge of the paper?
and what are the things that are excluded from the 2 point and middle vanishing points?such as roof tops.
can you move the middle vanishing point away from the middle?