shadow of a segment (center projection) Light rays parallel to the picture plane

Light rays parallel to the plane of the picture

Often, to simplify construction, the direction of the light rays is chosen parallel to the plane of the picture. In this case, the prospects for the horizontal projections of the light rays will be parallel to the base of the picture, and the prospects for the light rays will be parallel with each other. The angle of inclination of the light rays is selected depending on the required amount of shadow.