TileMapLoader -TizzyT

Imports System.Collections.Concurrent
Imports System.IO
Imports System.Threading
Public Class TileMapLoader
    Public Structure Coordinate
        Public H As Integer
        Public X, Y As UInteger
        Public Sub New(ByVal H As Integer, ByVal X As UInteger, ByVal Y As UInteger)
            Me.H = H : Me.X = X : Me.Y = Y
        End Sub
        Public Sub New(ByVal ID As String)
            Dim Parts As String() = ID.Split("-")
            H = Integer.Parse(Parts(0), Globalization.NumberStyles.HexNumber)
            X = UInteger.Parse(Parts(1), Globalization.NumberStyles.HexNumber)
            Y = UInteger.Parse(Parts(2), Globalization.NumberStyles.HexNumber)
        End Sub
        Public Overrides Function ToString() As String
            Return H.ToString("X8") & "-" & X.ToString("X8") & "-" & Y.ToString("X8")
        End Function
    End Structure
    Private Sections As New ConcurrentDictionary(Of Coordinate, Msec)
    Private DisposeThread As New Thread(Sub()
                                            While True
                                                For Each Msec As Msec In Sections.Values
                                                    Try
                                                        Msec.Age()
                                                    Catch ex As Exception
                                                    End Try
                                                Next
                                                Thread.Sleep(1000)
                                            End While
                                        End Sub)
    Public Sub New()
        DisposeThread.Start()
    End Sub
    Public Sub PreLoad(ByVal H As Integer, ByVal X As UInteger, ByVal Y As UInteger)
        Tile(H, X, Y)
        Tile(H, X - 250, Y - 250) : Tile(H, X, Y - 250) : Tile(H, X + 250, Y - 250)
        Tile(H, X - 250, Y) : Tile(H, X + 250, Y)
        Tile(H, X - 250, Y + 250) : Tile(H, X, Y + 250) : Tile(H, X + 250, Y + 250)
        Dim HH As Integer = H - 1
        Tile(HH, X, Y)
        Tile(HH, X - 250, Y - 250) : Tile(HH, X, Y - 250) : Tile(HH, X + 250, Y - 250)
        Tile(HH, X - 250, Y) : Tile(HH, X + 250, Y)
        Tile(HH, X - 250, Y + 250) : Tile(HH, X, Y + 250) : Tile(HH, X + 250, Y + 250)
        HH = H + 1
        Tile(HH, X, Y)
        Tile(HH, X - 250, Y - 250) : Tile(HH, X, Y - 250) : Tile(HH, X + 250, Y - 250)
        Tile(HH, X - 250, Y) : Tile(HH, X + 250, Y)
        Tile(HH, X - 250, Y + 250) : Tile(HH, X, Y + 250) : Tile(HH, X + 250, Y + 250)
    End Sub
    Public Function Tile(ByVal H As Integer, ByVal X As UInteger, ByVal Y As UInteger) As UInteger
        Dim Coordinate As New Coordinate(H, Math.Floor(X / 501), Math.Floor(Y / 501))
        If Sections.ContainsKey(Coordinate) Then
            Return Sections(Coordinate)(X Mod 501, Y Mod 501)
        Else
            Dim newMsec As New Msec(Coordinate)
            AddHandler newMsec.Expired, Sub()
                                            Dim M As Msec = Nothing
                                            If Sections.TryRemove(Coordinate, M) Then M.Dispose()
                                        End Sub
            Sections.TryAdd(Coordinate, newMsec)
            Return 0
        End If
    End Function
    Private Class Msec
        Implements IDisposable
        Public Event Expired()
        Private Tiles(500, 500) As UInteger
        Private Loaded As Boolean = False
        Private TTL As Byte = 20
        Private LoadThread As New Thread(Sub(ByVal Coord As Coordinate)
                                             Dim CoordStr As String = "Map\" & Coord.ToString & ".msec"
                                             Dim Data As Byte()
                                             If File.Exists(CoordStr) Then Data = File.ReadAllBytes(CoordStr) Else Exit Sub
                                             Try
                                                 Dim idx As Integer = 0
                                                 For y As Integer = 0 To 500
                                                     For x As Integer = 0 To 500
                                                         Tiles(x, y) = BitConverter.ToUInt32(Data, idx)
                                                         idx += 4
                                                     Next
                                                 Next
                                                 Loaded = True
                                             Catch ex As Exception
                                                 Erase Tiles
                                             Finally
                                                 Erase Data
                                             End Try
                                         End Sub)
        Default Public ReadOnly Property Tile(ByVal X As Integer, ByVal Y As Integer) As UInteger
            Get
                TTL = 60
                If Loaded Then Return Tiles(X, Y)
                Return 0
            End Get
        End Property
        Public Sub Age()
            If TTL > 0 Then TTL -= 1
            If TTL = 0 Then RaiseEvent Expired()
        End Sub
        Public Sub New(ByVal Coordinate As Coordinate)
            LoadThread.Start(Coordinate)
        End Sub
        Public Sub Dispose() Implements IDisposable.Dispose
            Try
                LoadThread.Abort()
            Catch ex As Exception
            End Try
            Loaded = False
            Erase Tiles
        End Sub
    End Class
End Class