Perspective drawing

About this course

Every perspective drawing is a picture traced on an imaginary sheet of glass between your eye and the world. In the 3D room you can walk round an eye point and a glass picture plane, switch between one-point, two-point and three-point views, raise your eye height and watch the horizon and the vanishing points move. The picture plane stands upright, and a sight line aimed at anything as high as your eye is level, so it crosses the glass at eye height. That is why the horizon line is your eye level.

The seven units are the picture plane, the horizon line, one-point perspective, two-point perspective, three-point perspective, measuring in depth, and Brunelleschi, Alberti and the history of perspective. Face the back wall square on and every depth edge in the room runs to one point straight ahead of your eye. In practice vanishing points often fall off the paper, so artists tape extra sheets to either side rather than move the points inward and distort the drawing. For equal spaces such as fence posts, a line from the top of post 1 through the middle of post 2 hits the ground line at the foot of post 3.

The last unit tells the history. The first correct method is credited to Filippo Brunelleschi (1377 to 1446), the Florentine architect who later built the great dome of Florence Cathedral, completed in 1436. The date of his discovery is not recorded exactly: the St Andrews history puts it at about 1413, and other accounts say about 1420. He painted two demonstration panels of Florence, one of the octagonal Baptistery of San Giovanni and one of the Palazzo dei Signori, both now lost.