DungeonMasterParser.DungeonMap.this C# (CSharp) Method

        public TileData this[int x, int y]
        {
            get
            {
                int relativeX = x - OffsetX;
                int relativeY = y - OffsetY;

                if (relativeX < 0 || relativeX >= Width || relativeY < 0 || relativeY >= Height )
                    return null;                
                
                return Tiles[relativeX * Height + relativeY];
            }
        }