From: The World In Your Head by Steven Lehar

Fig. 3.5 (A) The basic structural form of a simple object is recognized immediately independent of rotation, translation, and scale, as seen in this example which is easily distinguished from (B) similar shapes composed of different configurations of the same basic elements. (C) Recognition also occurs independent of perspective or elastic deformations, and (D) independent of the characteristics of the low-level edges or texture elements of which the stimulus is composed.