This design is created by a procedure called tritri (of course, you could choose a different name). How does tritri do it? What about these:






The name hints at the answer.Triangles are involved. So a good place to start is to make a procedure that will get the turtle to draw a triangle.
Playing turtle, that is, walking as a turtle would to make a triangle is a good way to start. As you play turtle the big issue arises. Is the triangle to have equal angles? If the triangle has equal angles like a square it would also have equal sides.
Remember when you begin a "turtle trip" you go through 360 degrees (or a multiple of 360) to return to your starting place. Thus making a triangle is like making a square except the rotations at the corners and the number of sides are different. The technical name for corner is vertex.

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