This lecture introduces the concept of the simple 2D transformations and how they are achieved in Processing. The transformations to be discussed are translation, scaling, rotation, and their combinations. Transformations make it simple to repeat shapes or images in different locations, sizes, and orientation.

Transformations are also useful when the creation of a shape is simpler to specify in an orientation that is different from the orientation within the final picture. For example, it is easier to specify the coordinates of the corners of a square when its sides are aligned with the vertical and horizontal than when the square is oriented at an arbitrary angle. Transformations make it possible to specify to coordinates in the simpler orientation, and then easily apply a rotation.