From 6a49a7ac40db5bc0c3216e43487ed2bd6f60d893 Mon Sep 17 00:00:00 2001
From: Corey Farwell <coreyf@rwell.org>
Date: Sun, 22 Mar 2020 16:09:49 -0400
Subject: [PATCH] Introduce Rect#to_polygon and Triangle#to_polygon.

Extracted from https://github.com/georust/geo/pull/421
---
 geo-types/src/rect.rs     | 35 ++++++++++++++++++++++++++++++++++-
 geo-types/src/triangle.rs | 29 ++++++++++++++++++++++++++++-
 2 files changed, 62 insertions(+), 2 deletions(-)

diff --git a/geo-types/src/rect.rs b/geo-types/src/rect.rs
index c5d67cb71..ea76295ef 100644
--- a/geo-types/src/rect.rs
+++ b/geo-types/src/rect.rs
@@ -1,4 +1,4 @@
-use crate::{Coordinate, CoordinateType};
+use crate::{polygon, Coordinate, CoordinateType, Polygon};
 
 /// A bounded 2D quadrilateral whose area is defined by minimum and maximum `Coordinates`.
 #[derive(PartialEq, Clone, Copy, Debug, Hash)]
@@ -73,6 +73,39 @@ impl<T: CoordinateType> Rect<T> {
         self.max().y - self.min().y
     }
 
+    /// Create a `Polygon` from the `Rect`.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// use geo_types::{Coordinate, Rect, polygon};
+    ///
+    /// let rect = Rect::new(
+    ///     Coordinate { x: 0., y: 0. },
+    ///     Coordinate { x: 10., y: 20. },
+    /// );
+    ///
+    /// assert_eq!(
+    ///     rect.to_polygon(),
+    ///     polygon![
+    ///         (x: 0., y: 0.),
+    ///         (x: 0., y: 20.),
+    ///         (x: 10., y: 20.),
+    ///         (x: 10., y: 0.),
+    ///         (x: 0., y: 0.),
+    ///     ],
+    /// );
+    /// ```
+    pub fn to_polygon(self) -> Polygon<T> {
+        polygon![
+            (x: self.min.x, y: self.min.y),
+            (x: self.min.x, y: self.max.y),
+            (x: self.max.x, y: self.max.y),
+            (x: self.max.x, y: self.min.y),
+            (x: self.min.x, y: self.min.y),
+        ]
+    }
+
     fn assert_valid_bounds(min: Coordinate<T>, max: Coordinate<T>) {
         assert!(
             min.x <= max.x && min.y <= max.y,
diff --git a/geo-types/src/triangle.rs b/geo-types/src/triangle.rs
index 03233e555..3cd4f137f 100644
--- a/geo-types/src/triangle.rs
+++ b/geo-types/src/triangle.rs
@@ -1,4 +1,4 @@
-use crate::{Coordinate, CoordinateType, Line};
+use crate::{polygon, Coordinate, CoordinateType, Line, Polygon};
 
 /// A bounded 2D area whose three vertices are defined by `Coordinate`s.
 #[derive(Copy, Clone, Debug, Hash)]
@@ -17,6 +17,33 @@ impl<T: CoordinateType> Triangle<T> {
             Line::new(self.2, self.0),
         ]
     }
+
+    /// Create a `Polygon` from the `Triangle`.
+    ///
+    /// # Examples
+    ///
+    /// ```rust
+    /// use geo_types::{Coordinate, Triangle, polygon};
+    ///
+    /// let triangle = Triangle(
+    ///     Coordinate { x: 0., y: 0. },
+    ///     Coordinate { x: 10., y: 20. },
+    ///     Coordinate { x: 20., y: -10. },
+    /// );
+    ///
+    /// assert_eq!(
+    ///     triangle.to_polygon(),
+    ///     polygon![
+    ///         (x: 0., y: 0.),
+    ///         (x: 10., y: 20.),
+    ///         (x: 20., y: -10.),
+    ///         (x: 0., y: 0.),
+    ///     ],
+    /// );
+    /// ```
+    pub fn to_polygon(self) -> Polygon<T> {
+        polygon![self.0, self.1, self.2, self.0]
+    }
 }
 
 impl<IC: Into<Coordinate<T>> + Copy, T: CoordinateType> From<[IC; 3]> for Triangle<T> {