This cushion shape is a semicircle joined with a rectangle. The "EDGE" measurement is the length of the straight part of the side, before the curve begins. The curved part of the cushion is a complete half circle.

If your cushion is just a half circle, use the "Semicircle Shape" instead. If the curve of your cushion is not a complete half circle, use the "Pattern Shape" to send us your own pattern.}