Don Hopkins, who also posts here, has an interesting essay on the design and implementations of pie menus from 1991: https://donhopkins.medium.com/the-design-an

Don Hopkins, who also posts here, has an interesting essay on the design and implementations of pie menus from 1991: https://donhopkins.medium.com/the-design-and-implementation-of-pie-menus-80db1e1b5293 https://donhopkins.medium.com/the-design-and-implementation-...