Monkey-X - Wall Tracing on Random Maps - code example

' Wall Tracing from the book Ai For Game Developers.
' Random Maps based on code from Rogue Basin.
'

Import mojo

'
'this is the wall tracing entity
Class entity
    Field tilex:Int,tiley:Int
    Field direction:Int=8
    Field speed:Int
    Method New()
        findstartposition
    End Method
    Method update()
        walltrace
    End Method
    Method walltrace()
        If direction = 4
            If mymap.map[tilex-1][tiley] = 1
                tilex -= 1
                direction = 2
            Elseif mymap.map[tilex][tiley+1] = 1
                tiley += 1
                direction = 4
            Elseif mymap.map[tilex+1][tiley] = 1
                tilex += 1
                direction = 6
            Elseif mymap.map[tilex][tiley-1] = 1
                tiley -= 1
                direction = 8
            End If
        Elseif direction = 6
            If mymap.map[tilex][tiley+1] = 1
                tiley += 1
                direction = 4
            Elseif mymap.map[tilex+1][tiley] = 1
                tilex += 1
                direction = 6
            Elseif mymap.map[tilex][tiley-1] = 1
                tiley -= 1
                direction = 8
            Elseif mymap.map[tilex-1][tiley] = 1
                tilex -= 1
                direction = 2
            End If
        Elseif direction = 8
            If mymap.map[tilex+1][tiley] = 1
                tilex += 1
                direction = 6
            Elseif mymap.map[tilex][tiley-1] = 1
                tiley -= 1
                direction = 8
            Elseif mymap.map[tilex-1][tiley] = 1
                tilex -= 1
                direction = 2
            Elseif mymap.map[tilex][tiley+1] = 1
                tiley += 1
                direction = 4
            End If
        Elseif direction = 2
            If mymap.map[tilex][tiley-1] = 1
                tiley -= 1
                direction = 8
            Elseif mymap.map[tilex-1][tiley] = 1
                tilex -= 1
                direction = 2
            Elseif mymap.map[tilex][tiley+1] = 1
                tiley += 1
                direction = 4
            Elseif mymap.map[tilex+1][tiley] = 1
                tilex += 1
                direction = 6
            End If
        End If


    End Method
    Method findstartposition()
        ' for tracing the wall we need to be sure
        ' that the entity is spawned against a wall
        ' here we check for a random pos on the map
        ' on the floor(1) with a wall(2) at y+1
        Local exitloop:Bool=False
        While exitloop = False
            Local x:Int=Rnd(3,mymap.mapwidth-3)
            Local y:Int=Rnd(3,mymap.mapheight-3)
            If mymap.map[x][y] = 1
            If mymap.map[x][y+1] = 2 
                exitloop = True
                tilex = x
                tiley = y
            End If
            End If
        Wend
    End Method    
    Method draw()
        SetColor 255,0,0
        DrawOval     tilex*mymap.tilewidth,
                    tiley*mymap.tileheight,
                    mymap.tilewidth+1,
                    mymap.tileheight+1
    End Method
End Class

Class map
    Field tilewidth:Float
    Field tileheight:Float
    Field mapwidth:Int
    Field mapheight:Int
    Field screenwidth:Int
    Field screenheight:Int
    Field map:Int[][]
    Method New(    screenwidth:Int,
                screenheight:Int,
                mapwidth:Int,
                mapheight:Int)
        Self.screenwidth = screenwidth
        Self.screenheight = screenheight
        Self.mapwidth = mapwidth
        Self.mapheight = mapheight
        Self.tilewidth = Float(screenwidth)/Float(mapwidth)
        Self.tileheight = Float(screenheight)/Float(mapheight)
        map = New Int[mapwidth][]
        For Local i=0 Until mapwidth
            map[i] = New Int[mapheight]
        Next
        map[mapwidth/2][mapheight/2] = 3 ' 3 is a door
        makemap
    End Method
    Method makemap()
        Local timeout:Int
        While timeout<(mapwidth*mapheight)*20
            timeout+=1
            Local x:Int=Rnd(11,mapwidth-11)
            Local y:Int=Rnd(11,mapheight-11)
            If map[x][y] = 3
                makeroom(x,y)
            End If
        Wend    
        'here we turn doors into walls
        'if they should be walls
        For Local y1=1 Until mapheight-1
        For Local x1=1 Until mapwidth-1
            If map[x1][y1] = 3
            Local cnt:Int=0
            For Local y2=y1-1 To y1+1
            For Local x2=x1-1 To x1+1
                If map[x2][y2] = 2 Then cnt+=1
            Next
            Next
            If cnt>3 Then map[x1][y1] = 2
            End If
        Next
        Next
        'here we turn doors into walls if they
        ' touch tiles that are nothing (0)
        For Local y1=1 Until mapheight-1
        For Local x1=1 Until mapwidth-1
            If map[x1][y1] = 3
            Local cnt:Int=0
            For Local y2=y1-1 To y1+1
            For Local x2=x1-1 To x1+1
                If map[x2][y2] = 0 Then cnt+=1
            Next
            Next
            If cnt>0 Then map[x1][y1] = 2
            End If
        Next
        Next        
        'here we turn the doors into floors
        For Local y1=0 Until mapheight
        For Local x1=0 Until mapwidth
            If map[x1][y1] = 3 Then map[x1][y1] = 1
        Next
        Next
    End Method
    Method makeroom(x:Int,y:Int)
        Local side:String
        If map[x][y-1] = 0
            side="up"
        Elseif map[x+1][y] = 0
            side="right"
        Elseif map[x][y+1] = 0
            side="down"
        Elseif map[x-1][y] = 0
            side="left"
        End If        
        Local w:Int=Rnd(5,10)
        Local h:Int=Rnd(5,10)
        If side="up"
            Local x1:Int=x-w/2
            Local y1:Int=y-h
            If roomfits(x1,y1,w,h)
                insertroom(x1,y1,w,h+1)
                'door up
                map[x1+Rnd(2,w-2)][y1] = 3
                ' door right
                map[x1+w-1][y1+Rnd(2,h-2)] = 3
                'door left
                map[x1][y1+Rnd(2,h-2)] = 3
            End If                        
            
        End If
        If side="right"
            Local x1:Int=x+1
            Local y1:Int=y-h/2
            If roomfits(x1,y1,w,h)
                insertroom(x1-1,y1,w,h)
                'door up
                map[x1+Rnd(2,w-2)][y1] = 3
                'door down
                map[x1+Rnd(2,w-2)][y1+h-1] = 3
                ' door right
                map[x1+w-2][y1+Rnd(2,h-2)] = 3                
            End If
        End If
        If side="left"
            Local x1:Int=x-w
            Local y1:Int=y-h/2
            If roomfits(x1,y1,w,h)
                insertroom(x1,y1,w+1,h)
                'door up
                map[x1+Rnd(2,w-2)][y1] = 3
                'door down
                map[x1+Rnd(2,w-2)][y1+h-1] = 3                
                'door left
                map[x1][y1+Rnd(2,h-2)] = 3

            End If            
        End If
        If side="down"
            Local x1:Int=x-w/2
            Local y1:Int=y+1
            If roomfits(x1,y1,w,h)
                insertroom(x1,y1-1,w,h)
                'door down
                map[x1+Rnd(2,w-2)][y1+h-2] = 3                
                'door left
                map[x1][y1+Rnd(2,h-2)] = 3                
                ' door right
                map[x1+w-1][y1+Rnd(2,h-2)] = 3                

            End If                        
        End If
    End Method
    Method insertroom(x,y,w,h)
        For Local y2=y Until y+h
        For Local x2=x Until x+w
            If map[x2][y2] <> 3 Then map[x2][y2] = 2
        Next
        Next

        For Local y2=y+1 Until y+h-1
        For Local x2=x+1 Until x+w-1
            map[x2][y2] = 1
        Next
        Next
    End Method
    Method roomfits(x:Int,y:Int,w:Int,h:Int)
        For Local y1=y Until y+h
        For Local x1=x Until x+w
            If map[x1][y1] = 1 Then Return False
        Next
        Next
        Return True
    End Method
    Method draw()
        For Local y=0 Until mapheight
        For Local x=0 Until mapwidth
            Select map[x][y]
                Case 0
                Case 1'floor
                SetColor 100,100,100
                DrawRect     x*tilewidth,
                            y*tileheight,
                            tilewidth+1,
                            tileheight+1
                Case 2'wall
                SetColor 200,200,200
                DrawRect     x*tilewidth,
                            y*tileheight,
                            tilewidth+1,
                            tileheight+1
                Case 3'wall
                SetColor 244,244,0
                DrawRect     x*tilewidth,
                            y*tileheight,
                            tilewidth+1,
                            tileheight+1

            End Select
        Next
        Next
    End Method
End Class

Global mymap:map
Global myentity:List<entity> = New List<entity>

Class MyGame Extends App
    Field cnt:Int
    Method OnCreate()
        SetUpdateRate(5)
        Seed = GetDate[4]+GetDate[5]
        newmap
    End Method
    Method OnUpdate()    
        cnt+=1
        For Local i:=Eachin myentity
            i.update
        Next
        If KeyHit(KEY_SPACE) Or cnt>200
            cnt=0
            newmap
        End If    
    End Method
    Method OnRender()
        Cls 0,0,0 
        mymap.draw
        For Local i:=Eachin myentity
            i.draw
        Next
        SetColor 255,255,255
        DrawText "Monkey-X - Wall Tracing on Random Maps",10,10
    End Method
End Class


Function Main()
    New MyGame()
End Function


Function newmap()
    Local s:Int=Rnd(40,100)
    mymap = New map(DeviceWidth,DeviceHeight,s,s)
    myentity = New List<entity>
    For Local i=0 Until Rnd(1,s/3)
        myentity.AddLast(New entity())
    Next
End Function