f5325bf597
Support rounded superellipse. Part of https://github.com/flutter/flutter/issues/139321 and https://github.com/flutter/flutter/issues/13914, also related to https://github.com/flutter/flutter/issues/91523. ### Open questions * Alternative names: * Round**ed**Superellipse * Squircle * ContinuousBorderRectangle (or something like this...) * I chose rounded superellipse because this name, albeit its length, precisely describe this shape. "Squircle" is not strictly defined but generally refers any shape intermediate between a rectangle and a circle. * Alternative definition for `corner_radius`: * Currently the `corner_radius` corresponds to SwiftUI parameters. To make the shape definition more generalized, we can instead define the `corner_radius` to be the radius of the corner circles, and make the framework do a look up table. * The down side is, not only the work to re-calculate the table, but also that it doesn't completely eliminates the relationship with SwiftUI, since currently the degree of the superellipse (`n`) is also mapped from the SwiftUI `cornerRadius`, which is not necessary for the shape per se. * To some extent it boils down to the question of whether we'd like this shape to support anything beyond SwiftUI. ### Demo https://github.com/user-attachments/assets/806ac0e9-d62f-4b04-ab6a-83436a11f6f3 Low ratio: (900, 900, 445) <img width="520" alt="image" src="https://github.com/user-attachments/assets/54087467-85cd-4021-91cc-a948866ab5a8"> Mid ratio: (900, 650, 180) <img width="508" alt="image" src="https://github.com/user-attachments/assets/460a4927-0396-462b-948d-0846a781c92c"> High ratio: (900, 650, 17) <img width="490" alt="image" src="https://github.com/user-attachments/assets/8d7f625d-8a3b-4aba-b3f9-f292b874b606"> ## Pre-launch Checklist - [ ] I read the [Contributor Guide] and followed the process outlined there for submitting PRs. - [ ] I read the [Tree Hygiene] wiki page, which explains my responsibilities. - [ ] I read and followed the [Flutter Style Guide] and the [C++, Objective-C, Java style guides]. - [ ] I listed at least one issue that this PR fixes in the description above. - [ ] I added new tests to check the change I am making or feature I am adding, or the PR is [test-exempt]. See [testing the engine] for instructions on writing and running engine tests. - [ ] I updated/added relevant documentation (doc comments with `///`). - [ ] I signed the [CLA]. - [ ] All existing and new tests are passing. If you need help, consider asking for advice on the #hackers-new channel on [Discord]. <!-- Links --> [Contributor Guide]: https://github.com/flutter/flutter/wiki/Tree-hygiene#overview [Tree Hygiene]: https://github.com/flutter/flutter/wiki/Tree-hygiene [test-exempt]: https://github.com/flutter/flutter/wiki/Tree-hygiene#tests [Flutter Style Guide]: https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo [C++, Objective-C, Java style guides]: https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#style [testing the engine]: https://github.com/flutter/flutter/wiki/Testing-the-engine [CLA]: https://cla.developers.google.com/ [flutter/tests]: https://github.com/flutter/tests [breaking change policy]: https://github.com/flutter/flutter/wiki/Tree-hygiene#handling-breaking-changes [Discord]: https://github.com/flutter/flutter/wiki/Chat