One-Point Perspective
Linear Perspective has two functions 1. create the illusion of spatial depth and 2. establish the viewer's location. There are two extreme points of view; bird's eye (above) and bug's eye (below). There are three tenets to remember when using linear perspective:
1. It uses a fixed point of view. If you move around you may change your eye level.
2. Parallel lines will appear to converge as they recede into space meeting at a point(s) located on the horizon line (eye level). Theses points are called vanishing points.
3. Objects equal in proportion will appear to diminish in size as they recede into space. (Ex. When observing a row of columns, the one in front will appear larger than the last column in line.)

Two-Point Perspective
There are three types of linear perspective: one-point, two-point and three-point. One and two-point are the most common. Three-point linear perspective uses the extreme points of view of bird's eye and bug's eye views.
"Divide and Conquer" Technique (Two-Point)
Archway demo