Implement image support for canvas widget

core/src/rectangle.rs

@@ -47,6 +47,62 @@ impl Rectangle<f32> {
         }
     }
 
+    /// Creates a new square [`Rectangle`] with the center at the origin and
+    /// with the given radius.
+    pub fn with_radius(radius: f32) -> Self {
+        Self {
+            x: -radius,
+            y: -radius,
+            width: radius * 2.0,
+            height: radius * 2.0,
+        }
+    }
+
+    /// Creates a new axis-aligned [`Rectangle`] from the given vertices; returning the
+    /// rotation in [`Radians`] that must be applied to the axis-aligned [`Rectangle`]
+    /// to obtain the desired result.
+    pub fn with_vertices(
+        top_left: Point,
+        top_right: Point,
+        bottom_left: Point,
+    ) -> (Rectangle, Radians) {
+        let width = (top_right.x - top_left.x).hypot(top_right.y - top_left.y);
+
+        let height =
+            (bottom_left.x - top_left.x).hypot(bottom_left.y - top_left.y);
+
+        let rotation =
+            (top_right.y - top_left.y).atan2(top_right.x - top_left.x);
+
+        let rotation = if rotation < 0.0 {
+            2.0 * std::f32::consts::PI + rotation
+        } else {
+            rotation
+        };
+
+        let position = {
+            let center = Point::new(
+                (top_right.x + bottom_left.x) / 2.0,
+                (top_right.y + bottom_left.y) / 2.0,
+            );
+
+            let rotation = -rotation - std::f32::consts::PI * 2.0;
+
+            Point::new(
+                center.x + (top_left.x - center.x) * rotation.cos()
+                    - (top_left.y - center.y) * rotation.sin(),
+                center.y
+                    + (top_left.x - center.x) * rotation.sin()
+                    + (top_left.y - center.y) * rotation.cos(),
+            )
+        };
+
+        (
+            Rectangle::new(position, Size::new(width, height)),
+            Radians(rotation),
+        )
+    }
+
     /// Returns the [`Point`] at the center of the [`Rectangle`].
     pub fn center(&self) -> Point {
         Point::new(self.center_x(), self.center_y())