Purpose of a two point perspective is to create an illusion of a three dimensional space on paper. In two point perspective, lines originate from the vanishing point.  The horizon line divides two planes and its where the “land meets the sky.” The horizon line is important for showing contrast as well. A low horizon focusses on the sky whereas a high horizon focuses on the land.

Drawing a cube around the horizon

Something that stands out in this video is that the horizon is the eye level. If the object is a placed above the horizon the base stands out. When the object is placed below the horizon, the ceiling stands out. Notice that the author uses free hand to draw and throws straight lines from the shoulder.

Drawing a Building in Two Point Perspective Part 1

 

The video shows how lines are originating from the vanishing point make the edges of a building. The author calls this the “kite stage”

 Drawing a Building in Two Point Perspective Part 2

In the second part of the video, the author adds an intersection and more buildings. Also note that the windows are in the direction of the vanishing point.