Drawing a foreshortened object is not easy. Your brain must overcome it’s ability to understand that the shape of an object does not really change as you observe it from different angles. This object permanence allows you to understand that a frisbee flying toward you does not really change shape as the observed angle changes. When we draw a foreshortened object you must undo this essential observation with your mind and draw the object as you really see it, not as you know it is shaped. Take the long body of a fish. As the fish rotates toward you, it goes from a long profile to a shortened three quarter view, to the compressed front view. Features on the body such as fin locations or the edge of the gill plate get closer together as the body shortens.
Click on the first image to start a step-by-step annotated slide show.