' Hilbert Curve using recursion

Mode 1,8

C = 1

Turtle Reset
Turtle Pen Up
Turtle Move 20,600
Turtle Pen Down

'Hilbert(Level,Angle,Length)
Hilbert(7,90,6)
Pause 10000

Turtle Reset
Turtle Pen Up
Turtle Move 150,550
Turtle Pen Down

Hilbert(8,90,2)
'Pause 10000

End


Sub Hilbert(Level,Angle,Length)
 If Level = 0 Then Exit Sub

 C = C + 0.1
 Turtle Pen Colour Map(C Mod 255)

 TurnTurtle(Angle)
 Hilbert(Level - 1,0 - Angle, Length)

 Turtle Forward Length
 TurnTurtle(0 - Angle)
 Hilbert(Level - 1,Angle,Length)

 Turtle Forward Length
 Hilbert(Level - 1,Angle,Length)

 TurnTurtle(0 - Angle)
 Turtle Forward Length
 Hilbert(Level - 1,0 - Angle,Length)

 TurnTurtle(Angle)

End Sub


Sub TurnTurtle(Angle)
 If Angle > 0 Then
   Turtle Turn Right Angle
 Else If Angle < 0 Then
   Turtle Turn Left Abs(Angle)
 End If
End Sub