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Draw fractal star

Draw fractal star recursively using the algorithm in the book by Robert Sedgewick 'Algorithms in C++'

Inputs
change r to have a denser or lighter pattern . 2..5 okay

Assumes
assume 800x600 screen res

Returns
Draws squares using lines 'b' style.

Side Effects
lower values of r increase the time to draw

Rate Draw fractal star

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(4(4 Vote))

'From the book by Robert Sedgewick 'Algorithms in C++'
'It is a very useful book. Can you find a non recursive way of doing this? 
'Recursion makes progs smaller and elegant whilst also making them
'more difficult to understand ( the implicit stack and unwinding of the calls)
Private Sub Form_Load()
Form1.WindowState = 2 'maximum
Form1.ScaleMode = 3 'pixel
Show
Call star(ScaleWidth \ 2, ScaleHeight \ 2, 90)
End Sub
Private Sub star(x As Integer, y As Integer, r As Integer)
If r > 1 Then
Call star(x - r, y + r, r \ 2)
Call star(x + r, y + r, r \ 2)
Call star(x - r, y - r, r \ 2)
Call star(x + r, y - r, r \ 2)
Call box(x, y, r)
End If

End Sub
Private Sub box(x1 As Integer, y1 As Integer, r1 As Integer)
Line (x1 - r1, y1 - r1)-(x1 + r1, y1 + r1), , B
'Form1.Circle (x1 - r1, y1 - r1), r1
'Line (x1 - r1, y1 - r1)-(x1 + r1, y1 - r1), , B
'Line -(x1 - (r1 \ 2), y1 + r1)
'Line -(x1 - r1, y1 - r1)
'trying to draw triangle instead of sqr- not work accurately

End Sub