Joona Aalto e1c8d60f91 Add winding order for Triangle2d (#10620) ... # Objective This PR adds some helpers for `Triangle2d` to work with its winding order. This could also be extended to polygons (and `Triangle3d` once it's added). ## Solution - Add `WindingOrder` enum with `Clockwise`, `Counterclockwise` and `Invalid` variants - `Invalid` is for cases where the winding order can not be reliably computed, i.e. the points lie on a single line and the area is zero - Add `Triangle2d::winding_order` method that uses a signed surface area to determine the winding order - Add `Triangle2d::reverse` method that reverses the winding order by swapping the second and third vertices The API looks like this: ```rust let mut triangle = Triangle2d::new( Vec2::new(0.0, 2.0), Vec2::new(-0.5, -1.2), Vec2::new(-1.0, -1.0), ); assert_eq!(triangle.winding_order(), WindingOrder::Clockwise); // Reverse winding order triangle.reverse(); assert_eq!(triangle.winding_order(), WindingOrder::Counterclockwise); ``` I also added tests to make sure the methods work correctly. For now, they live in the same file as the primitives. ## Open questions - Should it be `Counterclockwise` or `CounterClockwise`? The first one is more correct but perhaps a bit less readable. Counter-clockwise is also a valid spelling, but it seems to be a lot less common than counterclockwise. - Is `WindingOrder::Invalid` a good name? Parry uses `TriangleOrientation::Degenerate`, but I'm not a huge fan, at least as a non-native English speaker. Any better suggestions? - Is `WindingOrder` fine in `bevy_math::primitives`? It's not specific to a dimension, so I put it there for now.		2023-11-20 09:47:05 +00:00
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src	Add winding order for Triangle2d (#10620)	2023-11-20 09:47:05 +00:00
Cargo.toml	Add [lints] table, fix adding #![allow(clippy::type_complexity)] everywhere (#10011)	2023-11-18 20:58:48 +00:00