1//! Geometry module.
2
3mod angle;
4mod real;
5
6pub(crate) use angle::angle_consts;
7pub(crate) use angle::Trigonometry;
8pub use angle::{Angle, AngleUnit};
9pub use embedded_graphics_core::geometry::{
10 AnchorPoint, AnchorX, AnchorY, Dimensions, OriginDimensions, Point, Size,
11};
12pub(crate) use real::Real;
13
14pub(crate) trait PointExt {
15 /// Returns a point that is rotated by 90° relative to the origin.
16 fn rotate_90(self) -> Self;
17
18 /// Calculates the dot product of two points.
19 fn dot_product(self, other: Point) -> i32;
20
21 /// Calculates the determinant of a 2x2 matrix formed by this and another point.
22 ///
23 /// ```text
24 /// | self.x self.y |
25 /// result = | |
26 /// | other.x other.y |
27 /// ```
28 fn determinant(self, other: Point) -> i32;
29
30 /// Returns the squared length.
31 ///
32 /// The returned value is the square of the length of a vector from `(0, 0)`
33 /// to `(self.x, self.y)`.
34 fn length_squared(self) -> i32;
35}
36
37impl PointExt for Point {
38 fn rotate_90(self) -> Self {
39 Self::new(-self.y, self.x)
40 }
41
42 fn dot_product(self, other: Point) -> i32 {
43 self.x * other.x + self.y * other.y
44 }
45
46 fn determinant(self, other: Point) -> i32 {
47 self.x * other.y - self.y * other.x
48 }
49
50 fn length_squared(self) -> i32 {
51 self.x.pow(exp:2) + self.y.pow(exp:2)
52 }
53}
54
55#[cfg(test)]
56mod tests {
57 use super::*;
58
59 #[test]
60 fn check_length_squared() {
61 let p = Point::new(3, 4);
62
63 assert_eq!(p.length_squared(), 25);
64 }
65
66 #[test]
67 fn rotate_90() {
68 assert_eq!(Point::new(1, 0).rotate_90(), Point::new(0, 1));
69 assert_eq!(Point::new(0, -2).rotate_90(), Point::new(2, 0));
70 assert_eq!(Point::new(-3, 0).rotate_90(), Point::new(0, -3));
71 assert_eq!(Point::new(0, 4).rotate_90(), Point::new(-4, 0));
72 }
73}
74