They have a , a triangle and a square. Yes that is it. From this a whole scene is created like , humans, mountains, etc. Their paintings were monosyllabic.
It is understood that the circle and triangle come from their observation of nature, the circle representing , derived from mountains and pointed trees. Square is the only one that seems to obey a different logic and seems to be a human invention, indicating a sacred enclosure or a piece of land.
So the central motive in each ritual painting is the square, known as the 'Chauk' or 'Chaukat'. Simple formation however captures their lives.