Sometimes spherical triangles are used.In the first half of the 20th century, projecting a human head onto different projections was common to show how distortion varies across one projection as compared to another.In dynamic media, shapes of familiar coastlines and boundaries can be dragged across an interactive map to show how the projection distorts sizes and shapes according to position on the map.

Another way to visualize local distortion is through grayscale or color gradations whose shade