Ornament
Use the pen to select a colour and a symmetry type, then start drawing. Your drawing is repeated according to the chosen symmetry type. There are exactly 17 “wallpaper symmetry types”, as a rather difficult mathematical theorem states. All of these occur in islamic art.
The computer program offers an “analysis” part that supports determining the symmetry type of a given wallpaper. This is, however, difficult even with this help.
