My own try at A*

[Torahteen]

Woops! :oops: How silly of me.

Well... Here is the new code:

[syntax="qbasic"]DefInt A-Z
'$Dynamic

Declare Sub ClearScreen()
Declare Sub FindPath()
Declare Sub DrawScreen()


const Ground = 0
const Water = 1
const Hill = 2
const Start = 3
const Finish = 4
const False = 0
const True = Not False

const HillCost = 20
const GroundCost = 10

Type pSquareType
x As Integer
y As Integer
End Type

Type SquareType
pSquare As pSquareType
fScore As Integer
gScore As Integer
hScore As Integer
mType As Integer
onOpen As Integer
onClosed As Integer
End Type

Type AIType
x As Integer
y As Integer
End Type

Open "board.brd" For Input As #1
Input #1, sWidth, sHeight

Dim Shared Board(sWidth, sHeight) As SquareType
Dim Shared Path() As pSquareType
Dim Shared mStart As pSquareType
Dim Shared mFinish As pSquareType
Dim comp As AIType

For i = 1 To uBound(Board, 2)
For j = 1 to uBound(Board, 1)
Input #1, Board(i,j).mType
If Board(i,j).mType = Start Then
mStart.x = i
mStart.y = j
ElseIf Board(i,j).mType = Finish Then
mFinish.x = i
mFinish.y = j
End If
Next j
Next i

Screen 18
CLS

Board(mStart.x, mStart.y).onOpen = True
FindPath

i = 1
'Main Loop
Do
ClearScreen

comp.x = Path(i).x
comp.y = Path(i).y

DrawScreen

i = i + 1

Do While Inkey$ = ""
Loop

Loop

Sub FindPath()
'Using The A* Algorithm, find the shortest path to the End Point
Dim gScore

Dim c As pSquareType
c.x = mStart.x
c.y = mStart.y
For x = 1 to 3
For y = 1 to 3
Board((c.x + x),(c.y + y)).pSquare.x = mStart.x
Board((c.x + x),(c.y + y)).pSquare.y = mStart.y
Next y
Next x

Do While onFinish = False
Board(c.x,c.y).onClosed = True
For x = 1 to 3
For y = 1 to 3

If Not Board((c.x + x),(c.y + y)).onClosed = True Then 'If it's not on the closed list
If Not Board((c.x + x),(c.y + y)).mType = Water Then 'If it's not a water tile
If Board((c.x + x),(c.y + y)).onOpen = False Then 'If it's not on the open list

Board((c.x + x),(c.y + y)).onOpen = True
If Board((c.x + x),(c.y + y)).mType = Hill Then
Board((c.x + x),(c.y + y)).gScore = HillCost
Else
Board((c.x + x),(c.y + y)).gScore = GroundCost
End If

hx = ABS(mFinish.x - (c.x + x))
hy = ABS(mFinish.y - (c.y + y))

Board((c.x + x),(c.y + y)).hScore = hx + hy
Board((c.x + x),(c.y + y)).fScore = Board((c.x + x),(c.y + y)).gScore + Board((c.x + x),(c.y + y)).hScore

Board((c.x + x),(c.y + y)).pSquare.x = c.x
Board((c.x + x),(c.y + y)).pSquare.y = c.y
If c.x + x = mFinish.x And c.y + y = mFinish.y Then 'We've made it to the finish!
onFinish = True
End If
Else 'Then it is on the open list

If Board((c.x + x),(c.y + y)).mType = Hill Then
tempG = HillCost
Else
tempG = GroundCost
End If

If Board((c.x + x),(c.y + y)).gScore > (Board(c.x,c.y).gScore + tempG) Then
Board((c.x + x),(c.y + y)).pSquare.x = c.x
Board((c.x + x),(c.y + y)).pSquare.y = c.y
End If

End If
End If
End If
Next y
Next x
curScore = 20000
For y = 1 to uBound(Board, 2)
For x = 1 to uBound(Board, 1)
If Board(x,y).onOpen = True Then
If Board(x,y).fScore < curScore Then
c.x = x
c.y = y
curScore = Board(x,y).fScore
End If
End If
Next x
Next y

Loop
'We've found the finish square. Time to walk backwards to get our path

Dim tempPath(sWidth*sHeight) As pSquareType
Dim t As pSquareType
t.x = mFinish.x
t.y = mFinish.y
i = 1
tempPath(i).x = t.x
tempPath(i).y = t.y

Do While EndOfPath = False
i = i + 1
tempPath(i).x = Board(t.x,t.y).pSquare.x
tempPath(i).y = Board(t.x,t.y).pSquare.y
t.x = Board(tempPath(i).x, tempPath(i).y).pSquare.x
t.y = Board(tempPath(i).x, tempPath(i).y).pSquare.y

If t.x = mStart.x And t.y = mStart.y Then
EndOfPath = True
End If

Loop
EndOfPath = False
j = 1
Do While i <> False
Path(j).x = tempPath(i).x
Path(j).y = tempPath(i).y
i = i - 1
j = j + 1
Loop

End Sub

Sub ClearScreen()
Line (0,0)-(640,480),0,BF
End Sub

Sub DrawScreen
For y = 1 to uBound(Board,2)
For x = 1 to uBound(Board,1)
If Board(x,y).mType = Ground Then
Line (x * 10, y * 10) - ((x * 10 + 10), (y * 10 + 10)), 2, BF
ElseIf Board(x,y).mType = Hill Then
Line (x * 10, y * 10) - ((x * 10 + 10), (y * 10 + 10)), 21, BF
ElseIf Board(x,y).mType = Water Then
Line (x * 10, y * 10) - ((x * 10 + 10), (y * 10 + 10)), 33, BF
ElseIf Board(x,y).mType = Start Then
Line (x * 10, y * 10) - ((x * 10 + 10), (y * 10 + 10)), 15, BF
ElseIf Board(x,y).mType = Finish Then
Line (x * 10, y * 10) - ((x * 10 + 10), (y * 10 + 10)), 4, BF
End If

Circle ((comp.x * 10 + 5), (comp.y * 10 + 5)), 3, 14

Locate 1,1
Print "Press Any Key to Continue"

Next x
Next y
End Sub
[/syntax]

I'm still stuck. Anybody have any idea why it doesn't do anything?