Simplify functions + Add new Rhombus creators

Co-authored-by: Luís Figueiredo <[email protected]>

crates/bevy_math/src/bounding/bounded2d/primitive_impls.rs

@@ -187,23 +187,18 @@ impl Bounded2d for Rhombus {
     fn aabb_2d(&self, translation: Vec2, rotation: impl Into<Rotation2d>) -> Aabb2d {
         let rotation_mat = rotation.into();
 
-        let [a, b, c, d] = [
-            rotation_mat * Vec2::new(self.half_diagonals.x, 0.0) + translation,
-            rotation_mat * Vec2::new(0.0, self.half_diagonals.y) + translation,
-            rotation_mat * Vec2::new(-self.half_diagonals.x, 0.0) + translation,
-            rotation_mat * Vec2::new(0.0, -self.half_diagonals.y) + translation,
+        let [rotated_x_half_diagonal, rotated_y_half_diagonal] = [
+            rotation_mat * Vec2::new(self.half_diagonals.x, 0.0),
+            rotation_mat * Vec2::new(0.0, self.half_diagonals.y),
         ];
+        let aabb_half_extent = rotated_x_half_diagonal
+            .abs()
+            .max(rotated_y_half_diagonal.abs());
 
-        let min = Vec2::new(
-            a.x.min(b.x).min(c.x).min(d.x),
-            a.y.min(b.y).min(c.y).min(d.y),
-        );
-        let max = Vec2::new(
-            a.x.max(b.x).max(c.x).max(d.x),
-            a.y.max(b.y).max(c.y).max(d.y),
-        );
-
-        Aabb2d { min, max }
+        Aabb2d {
+            min: -aabb_half_extent + translation,
+            max: aabb_half_extent + translation,
+        }
     }
 
     fn bounding_circle(
@@ -813,6 +808,17 @@ mod tests {
         let bounding_circle = rhombus.bounding_circle(translation, std::f32::consts::FRAC_PI_4);
         assert_eq!(bounding_circle.center, translation);
         assert_eq!(bounding_circle.radius(), 1.0);
+
+        let rhombus = Rhombus::new(0.0, 0.0);
+        let translation = Vec2::new(0.0, 0.0);
+
+        let aabb = rhombus.aabb_2d(translation, std::f32::consts::FRAC_PI_4);
+        assert_eq!(aabb.min, Vec2::new(0.0, 0.0));
+        assert_eq!(aabb.max, Vec2::new(0.0, 0.0));
+
+        let bounding_circle = rhombus.bounding_circle(translation, std::f32::consts::FRAC_PI_4);
+        assert_eq!(bounding_circle.center, translation);
+        assert_eq!(bounding_circle.radius(), 0.0);
     }
 
     #[test]

crates/bevy_math/src/primitives/dim2.rs

@@ -957,10 +957,27 @@ impl Rhombus {
         }
     }
 
+    /// Create a new `Rhombus` from a side length with all inner angles equal.
+    #[inline(always)]
+    pub fn from_side(side: f32) -> Self {
+        Self {
+            half_diagonals: Vec2::new(side.hypot(side) / 2.0, side.hypot(side) / 2.0),
+        }
+    }
+
+    /// Create a new `Rhombus` from a given inradius with all inner angles equal.
+    #[inline(always)]
+    pub fn from_inradius(inradius: f32) -> Self {
+        let half_diagonal = inradius * 2.0 / std::f32::consts::SQRT_2;
+        Self {
+            half_diagonals: Vec2::new(half_diagonal, half_diagonal),
+        }
+    }
+
     /// Get the length of each side of the rhombus
     #[inline(always)]
     pub fn side(&self) -> f32 {
-        (self.half_diagonals.x.powi(2) + self.half_diagonals.y.powi(2)).sqrt()
+        self.half_diagonals.x.hypot(self.half_diagonals.y)
     }
 
     /// Get the radius of the circumcircle on which all vertices
@@ -975,10 +992,7 @@ impl Rhombus {
     #[inline(always)]
     #[doc(alias = "apothem")]
     pub fn inradius(&self) -> f32 {
-        let horizontal_diagonal = self.half_diagonals.x * 2.0;
-        let vertical_diagonal = self.half_diagonals.y * 2.0;
-        (horizontal_diagonal * vertical_diagonal)
-            / (2.0 * (horizontal_diagonal.powi(2) + vertical_diagonal.powi(2)).sqrt())
+        ((self.half_diagonals.x * self.half_diagonals.y) / self.side()).max(0.0)
     }
 
     /// Finds the point on the rhombus that is closest to the given `point`.
@@ -1032,13 +1046,13 @@ impl Measured2d for Rhombus {
     /// Get the area of the rhombus
     #[inline(always)]
     fn area(&self) -> f32 {
-        (self.half_diagonals.x * 2.0) * (self.half_diagonals.y * 2.0) / 2.0
+        2.0 * self.half_diagonals.x * self.half_diagonals.y
     }
 
     /// Get the perimeter of the rhombus
     #[inline(always)]
     fn perimeter(&self) -> f32 {
-        2.0 * ((self.half_diagonals.x * 2.0).powi(2) + (self.half_diagonals.y * 2.0).powi(2)).sqrt()
+        4.0 * self.side()
     }
 }
 
@@ -1751,6 +1765,20 @@ mod tests {
         assert_eq!(rhombus.area(), 6.0, "incorrect area");
         assert_eq!(rhombus.perimeter(), 10.0, "incorrect perimeter");
         assert_eq!(rhombus.side(), 2.5, "incorrect side");
+        assert_eq!(rhombus.inradius(), 1.2, "incorrect inradius");
+        assert_eq!(rhombus.circumradius(), 2.0, "incorrect circumradius");
+        let rhombus = Rhombus::new(0.0, 0.0);
+        assert_eq!(rhombus.area(), 0.0, "incorrect area");
+        assert_eq!(rhombus.perimeter(), 0.0, "incorrect perimeter");
+        assert_eq!(rhombus.side(), 0.0, "incorrect side");
+        assert_eq!(rhombus.inradius(), 0.0, "incorrect inradius");
+        assert_eq!(rhombus.circumradius(), 0.0, "incorrect circumradius");
+        let rhombus = Rhombus::from_side(std::f32::consts::SQRT_2);
+        assert_eq!(rhombus, Rhombus::new(2.0, 2.0));
+        assert_eq!(
+            rhombus,
+            Rhombus::from_inradius(std::f32::consts::FRAC_1_SQRT_2)
+        );
     }
 
     #[test]

examples/2d/2d_shapes.rs

@@ -12,7 +12,7 @@ fn main() {
         .run();
 }
 
-const X_EXTENT: f32 = 640.;
+const X_EXTENT: f32 = 900.;
 
 fn setup(
     mut commands: Commands,