Free, commercially distributable, modifiable, open source code. This class is part of the XnaGeometry library, a 3d library. To download the entire XnaGeometry library, click here. XnaGeometry uses the same function names as XNA so you can use the Microsoft XNA documentation. XnaGeometry will allow you to decouple your calculations from the renderer, and uses doubles for precision. Monogame has rendering support.

#region License
/*
MIT License
Copyright © 2006 The Mono.Xna Team

All rights reserved.

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
#endregion License

using System;
using System.Globalization;
using System.ComponentModel;

namespace XnaGeometry
{

    public struct Rectangle : IEquatable<Rectangle>
    {
        #region Private Fields

        private static Rectangle emptyRectangle = new Rectangle();

        #endregion Private Fields


        #region Public Fields

        public int X;
        public int Y;
        public int Width;
        public int Height;

        #endregion Public Fields


        #region Public Properties

        public static Rectangle Empty
        {
            get { return emptyRectangle; }
        }

        public int Left
        {
            get { return this.X; }
        }

        public int Right
        {
            get { return (this.X + this.Width); }
        }

        public int Top
        {
            get { return this.Y; }
        }

        public int Bottom
        {
            get { return (this.Y + this.Height); }
        }

        #endregion Public Properties


        #region Constructors

        public Rectangle(int x, int y, int width, int height)
        {
            this.X = x;
            this.Y = y;
            this.Width = width;
            this.Height = height;
        }

        #endregion Constructors


        #region Public Methods

        public static bool operator ==(Rectangle a, Rectangle b)
        {
            return ((a.X == b.X) && (a.Y == b.Y) && (a.Width == b.Width) && (a.Height == b.Height));
        }

        public bool Contains(int x, int y)
        {
            return ((((this.X <= x) && (x < (this.X + this.Width))) && (this.Y <= y)) && (y < (this.Y + this.Height)));
        }
        
        public bool Contains(Point value)
        {
            return ((((this.X <= value.X) && (value.X < (this.X + this.Width))) && (this.Y <= value.Y)) && (value.Y < (this.Y + this.Height)));
        }

        public bool Contains(Rectangle value)
        {
            return ((((this.X <= value.X) && ((value.X + value.Width) <= (this.X + this.Width))) && (this.Y <= value.Y)) && ((value.Y + value.Height) <= (this.Y + this.Height)));
        }

        public static bool operator !=(Rectangle a, Rectangle b)
        {
            return !(a == b);
        }

        public void Offset(Point offset)
        {
            X += offset.X;
            Y += offset.Y;
        }

        public void Offset(int offsetX, int offsetY)
        {
            X += offsetX;
            Y += offsetY;
        }
        
        public Point Location
        {
            get 
            {
                return new Point(this.X, this.Y);
            }
            set
            {
                X = value.X;
                Y = value.Y;
            }
        }
        
        public Point Center
        {
            get 
            {
                // This is incorrect
                //return new Point( (this.X + this.Width) / 2,(this.Y + this.Height) / 2 );
                // What we want is the Center of the rectangle from the X and Y Origins
                return new Point(this.X + (this.Width / 2), this.Y + (this.Height / 2));
            }
        }




        public void Inflate(int horizontalValue, int verticalValue)
        {
            X -= horizontalValue;
            Y -= verticalValue;
            Width += horizontalValue * 2;
            Height += verticalValue * 2;
        }
        
        public bool IsEmpty
        {
            get
            {
                return ((((this.Width == 0) && (this.Height == 0)) && (this.X == 0)) && (this.Y == 0));
            }
        }

        public bool Equals(Rectangle other)
        {
            return this == other;
        }

        public override bool Equals(object obj)
        {
            return (obj is Rectangle) ? this == ((Rectangle)obj) : false;
        }

        public override string ToString()
        {
            return string.Format("{{X:{0} Y:{1} Width:{2} Height:{3}}}", X, Y, Width, Height);
        }

        public override int GetHashCode()
        {
            return (this.X ^ this.Y ^ this.Width ^ this.Height);
        }

        public bool Intersects(Rectangle value)
        {
            return value.Left < Right       && 
                   Left       < value.Right && 
                   value.Top  < Bottom      &&
                   Top        < value.Bottom;            
        }


        public void Intersects(ref Rectangle value, out bool result)
        {
            result = value.Left < Right       && 
                     Left       < value.Right && 
                     value.Top  < Bottom      &&
                     Top        < value.Bottom;
        }

        public static Rectangle Intersect(Rectangle value1, Rectangle value2)
        {
            Rectangle rectangle;
            Intersect(ref value1, ref value2, out rectangle);
            return rectangle;
        }


        public static void Intersect(ref Rectangle value1, ref Rectangle value2, out Rectangle result)
        {
            if (value1.Intersects(value2))
            {
                int right_side = Math.Min(value1.X + value1.Width, value2.X + value2.Width);
                int left_side = Math.Max(value1.X, value2.X);
                int top_side = Math.Max(value1.Y, value2.Y);
                int bottom_side = Math.Min(value1.Y + value1.Height, value2.Y + value2.Height);
                result = new Rectangle(left_side, top_side, right_side - left_side, bottom_side - top_side);
            }
            else
            {
                result = new Rectangle(0, 0, 0, 0);
            }
        }
        
        public static Rectangle Union(Rectangle value1, Rectangle value2)
        {
            int x = Math.Min (value1.X, value2.X);
            int y = Math.Min (value1.Y, value2.Y);
            return new Rectangle(x, y,
                                 Math.Max (value1.Right, value2.Right) - x,
                                     Math.Max (value1.Bottom, value2.Bottom) - y);
        }
        
        public static void Union(ref Rectangle value1, ref Rectangle value2, out Rectangle result)
        {
            result.X = Math.Min (value1.X, value2.X);
            result.Y = Math.Min (value1.Y, value2.Y);
            result.Width = Math.Max (value1.Right, value2.Right) - result.X;
            result.Height = Math.Max (value1.Bottom, value2.Bottom) - result.Y;
        }
                
        #endregion Public Methods
    }
}