Add Rectangle

src/PolyZone/Shapes/Interfaces/IRectangle.cs

@@ -0,0 +1,6 @@
+namespace PolyZone.Shapes.Interfaces;
+
+/// <summary>
+/// A 2d rectangle / box
+/// </summary>
+public interface IRectangle : ISpatial2dShape;

src/PolyZone/Shapes/Polygon.cs

@@ -9,15 +9,14 @@ namespace PolyZone.Shapes;
 /// <param name="points">A list of <see cref="Vector2"/> in sequential order, to make-up a polygonal shape</param>
 public class Polygon(IReadOnlyList<Vector2> points) : IPolygon
 {
-    private Vector2? _min;
-    private Vector2? _max;
+    private Rectangle? _boundingBox = null;
 
     public IReadOnlyList<Vector2> Points { get; } = points;
 
     /// <inheritdoc cref="ISpatial2dShape.Contains"/>
     public bool Contains(in Vector2 point)
     {
-        if (_min is null || _max is null)
+        if (_boundingBox is null)
         {
             float minX = float.MaxValue, minY = float.MaxValue;
             float maxX = float.MinValue, maxY = float.MinValue;
@@ -30,22 +29,20 @@ public bool Contains(in Vector2 point)
                 maxY = Math.Max(maxY, vertex.Y);
             }
 
-            _min = new Vector2 { X = minX, Y = minY };
-            _max = new Vector2 { X = maxX, Y = maxY };
+            _boundingBox = new Rectangle(new Vector2 { X = minX, Y = minY }, new Vector2 { X = maxX, Y = maxY });
         }
 
-        return Contains(point, Points, _min.Value, _max.Value);
+        return Contains(point, Points, _boundingBox);
     }
 
     /// <inheritdoc cref="ISpatial2dShape.DistanceFrom"/>
     public float DistanceFrom(in Vector2 point) => DistanceFrom(point, Points);
 
     // https://web.archive.org/web/20210225074947/http://geomalgorithms.com/a03-_inclusion.html
-    private static bool Contains(in Vector2 point, IReadOnlyList<Vector2> polygon, in Vector2 boundingBoxMin, in Vector2 boundingBoxMax)
+    private static bool Contains(in Vector2 point, IReadOnlyList<Vector2> polygon, in Rectangle boundingBox)
     {
-        if (point.X < boundingBoxMin.X || point.X > boundingBoxMax.X || point.Y < boundingBoxMin.Y || point.Y > boundingBoxMax.Y)
+        if (!boundingBox.Contains(point))
         {
-            // Point is outside the bounding box, so it's definitely outside the polygon
             return false;
         }
 

src/PolyZone/Shapes/Rectangle.cs

@@ -0,0 +1,27 @@
+using CitizenFX.Core;
+using PolyZone.Shapes.Interfaces;
+
+namespace PolyZone.Shapes;
+
+public class Rectangle(in Vector2 upperLeft, in Vector2 bottomRight) : IRectangle
+{
+    public Vector2 UpperLeft { get; } = upperLeft;
+    public Vector2 BottomRight { get; } = bottomRight;
+
+    /// <inheritdoc cref="ISpatial2dShape.Contains"/>
+    public bool Contains(in Vector2 point)
+    {
+        return point.X >= UpperLeft.X && point.X <= BottomRight.X &&
+               point.Y >= UpperLeft.Y && point.Y <= BottomRight.Y;
+    }
+
+    /// <inheritdoc cref="ISpatial2dShape.DistanceFrom"/>
+    public float DistanceFrom(in Vector2 point)
+    {
+        // Calculate the distance using Euclidean distance formula
+        var dx = Math.Max(Math.Max(UpperLeft.X - point.X, 0), point.X - BottomRight.X);
+        var dy = Math.Max(Math.Max(UpperLeft.Y - point.Y, 0), point.Y - BottomRight.Y);
+
+        return (float) Math.Sqrt(dx * dx + dy * dy);    
+    }
+}