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Voile/Source/Rect.cs

@@ -20,4 +20,62 @@ public record Rect(float Width = 0.0f, float Height = 0.0f)
     public static bool operator <(Rect left, Rect right) => left.CompareTo(right) < 0;
     public static bool operator >=(Rect left, Rect right) => left.CompareTo(right) >= 0;
     public static bool operator <=(Rect left, Rect right) => left.CompareTo(right) <= 0;
+}
+
+/// <summary>
+/// Represents the size offsets applied around a rectangle.
+/// </summary>
+public struct Size : IEquatable<Size>
+{
+    public float Left;
+    public float Right;
+    public float Top;
+    public float Bottom;
+
+    public Size(float uniform)
+    {
+        Left = Right = Top = Bottom = uniform;
+    }
+
+    public Size(float horizontal, float vertical)
+    {
+        Left = Right = horizontal;
+        Top = Bottom = vertical;
+    }
+
+    public Size(float left, float right, float top, float bottom)
+    {
+        Left = left;
+        Right = right;
+        Top = top;
+        Bottom = bottom;
+    }
+
+    public static Size Zero => new Size(0);
+
+    public static Rect operator +(Size margin, Rect rect) =>
+        new Rect(rect.Width + margin.Left + margin.Right,
+                 rect.Height + margin.Top + margin.Bottom);
+
+    public static Rect operator +(Rect rect, Size margin) =>
+        margin + rect;
+
+
+    public static bool operator ==(Size a, Size b) =>
+a.Equals(b);
+
+    public static bool operator !=(Size a, Size b) =>
+        !a.Equals(b);
+
+    public bool Equals(Size other) =>
+        Left == other.Left &&
+        Right == other.Right &&
+        Top == other.Top &&
+        Bottom == other.Bottom;
+
+    public override bool Equals(object? obj) =>
+        obj is Size other && Equals(other);
+
+    public override int GetHashCode() =>
+        HashCode.Combine(Left, Right, Top, Bottom);
 }