(12) Shape Constancy

Shape constancy is the tendency to perceive the shape of a rigid object as constant despite differences in the viewing angle. This means that when we see a door open, we see it as a rectangle in it's beginning stages of being closed. Then as it starts to move, the door actually appears to be trapezoidal, but our brain still tells us that it is rectangular.

This is a similar example to the door, but it is going to use a laptop. When it starts open, we perceive the screen to be rectangular, then as it gets to about a 45 degree angle, the screen appears to be trapezoidal because of the differing angles of the screen, but our brains still tell us that it is rectangular.

As one can see, the first picture is much more noticeably a rectangle compared to the second picture. Because of depth perception, the rectangle in the second picture is more resembled to a trapezoid, but our brains take shortcuts and just tell us that it is a rectangle from start to finish.