Revisit the Game of Life while Learning about Extension Methods in C#

using System;
using System.Collections.Generic;
using System.Text;
using System.Drawing;
using System.Drawing.Drawing2D;

namespace LifeSimulation.Extensions
{
    static class ProcessLifeModelExtension
    {
        private enum CellOutcome
        {
            Dies,
            Spawns,
            NoChange
        }

        #region Extension methods

        public static void Process(this LifeModelBase model, World World)
        {
            List<Point> dieList = new List<Point>();
            List<Point> spawnList = new List<Point>();
            for (int i = 0; i < World.Space.GetLength(0); i++)
            {
                for (int j = 0; j < World.Space.GetLength(1); j++)
                {
                    switch (model.GetCellOutcome(World, i, j))
                    {
                        case CellOutcome.Dies:
                            dieList.Add(new Point(i, j));
                            break;
                        case CellOutcome.Spawns:
                            spawnList.Add(new Point(i, j));
                            break;
                    }
                }
            }

            //Die
            foreach (Point point in dieList)
                World.Space[point.X, point.Y] = 0;
            //Spawn
            foreach (Point point in spawnList)
                World.Space[point.X, point.Y] = model.MaximumAge;

            //Age
            for (int i = 0; i < World.Space.GetLength(0); i++)
                for (int j = 0; j < World.Space.GetLength(1); j++)
                    if (World.Space[i, j] > 0)
                        World.Space[i, j]--;
        }

        public static int GetMaximumNeighbours(this LifeModelBase model)
        {
            return GetMaximumNeighbours(model.NeighbourDistance);
        }

        #endregion

        #region Public methods
        /// <summary>
        /// Gets max number of neighbours according to distance indicator as follows...
        /// 
        /// Distance = 1
        /// 00000
        /// 00100
        /// 01X10
        /// 00100
        /// 00000
        /// Distance = 2
        /// 00000
        /// 01110
        /// 01X10
        /// 01110
        /// 00000
        /// Distance = 3
        /// 00100
        /// 01110
        /// 11X11
        /// 01110
        /// 00100
        /// Distance = 4
        /// 01110
        /// 11111
        /// 11X11
        /// 11111
        /// 01110
        /// Distance = 5 or more
        /// 11111
        /// 11111
        /// 11X11
        /// 11111
        /// 11111
        /// </summary>
        /// <param name="neighbourhoodDistance"></param>
        public static int GetMaximumNeighbours(int neighbourhoodDistance)
        {
            switch (neighbourhoodDistance)
            {
                case 1: return 4;
                case 2: return 8;
                case 3: return 12;
                case 4: return 20;
                default: return 24;
            }
        }

        #endregion

        #region Private methods
        private static CellOutcome GetCellOutcome(this LifeModelBase model, World World, int i, int j)
        {
            World.Neighbours[i, j] = World.CountNeighbours(i, j, model.NeighbourDistance);
            if (World.Space[i, j] > 0)
            {
                if (model.CellDeathIndicators.Contains(World.Neighbours[i, j]))
                    return CellOutcome.Dies;
            }
            else
            {
                if (model.CellSpawnIndicators.Contains(World.Neighbours[i, j]))
                    return CellOutcome.Spawns;
            }
            return CellOutcome.NoChange;
        }


        private static int CountNeighbours(this World World, int i, int j, int distance)
        {
            int c = 0;
            int mi = World.Space.GetLength(0) - 1;
            int mj = World.Space.GetLength(1) - 1;
            int mi2 = mi - 1;
            int mj2 = mj - 1;

            if (distance >= 1)
            {
                if (i > 0 && World.Space[i - 1, j] > 0) c++;
                if (i < mi && World.Space[i + 1, j] > 0) c++;
                if (j > 0 && World.Space[i, j - 1] > 0) c++;
                if (j < mj && World.Space[i, j + 1] > 0) c++;
            }
            if (distance >= 2)
            {
                if (i > 0 && j > 0 && World.Space[i - 1, j - 1] > 0) c++;
                if (i > 0 && j < mj && World.Space[i - 1, j + 1] > 0) c++;
                if (i < mi && j > 0 && World.Space[i + 1, j - 1] > 0) c++;
                if (i < mi && j < mj && World.Space[i + 1, j + 1] > 0) c++;
            }
            if (distance >= 3)
            {
                if (i > 1 && World.Space[i - 2, j] > 0) c++;
                if (i < mi2 && World.Space[i + 2, j] > 0) c++;
                if (j > 1 && World.Space[i, j - 2] > 0) c++;
                if (j < mj2 && World.Space[i, j + 2] > 0) c++;
            }
            if (distance >= 4)
            {
                //Left top
                if (i > 1 && j > 0 && World.Space[i - 2, j - 1] > 0) c++;
                if (i > 0 && j > 1 && World.Space[i - 1, j - 2] > 0) c++;
                //Left bottom
                if (i > 1 && j < mj && World.Space[i - 2, j + 1] > 0) c++;
                if (i > 0 && j < mj2 && World.Space[i - 1, j + 2] > 0) c++;
                //Right top
                if (i < mi2 && j > 0 && World.Space[i + 2, j - 1] > 0) c++;
                if (i < mi && j > 1 && World.Space[i + 1, j - 2] > 0) c++;
                //Right bottom
                if (i < mi2 && j < mj && World.Space[i + 2, j + 1] > 0) c++;
                if (i < mi && j < mj2 && World.Space[i + 1, j + 2] > 0) c++;
            }
            if (distance >= 5)
            {
                //Left top
                if (i > 1 && j > 1 && World.Space[i - 2, j - 2] > 0) c++;
                //Left bottom
                if (i > 1 && j < mj2 && World.Space[i - 2, j + 2] > 0) c++;
                //Right top
                if (i < mi2 && j > 1 && World.Space[i + 2, j - 2] > 0) c++;
                //Right bottom
                if (i < mi2 && j < mj2 && World.Space[i + 2, j + 2] > 0) c++;
            }

            return c;
        }
        #endregion

    }
}