What if I add some half-square triangles to a ninepatch grid?
Because it's a pinwheel made using ninepatch blocks, I call this a ninepatch pinwheel block.
It turns out that my ninepatch pinwheel block, which I decided to name Campsie, is a tessellation. The blues form a shape that is identical to the shape formed by the yellows. When a single shape combines to fill a space the result is a tessellation.
Tomorrow I'll show you another ninepatch pinwheel block.