Logo Arts

To New
  # set default screen, pen and turtle values
  ResetAll SetScreenSize [400 400] HideTurtle
  SetSC Black SetPC Green SetPS 1 PenUp
End

To Display :LSys :Order
  # write header title, curve depth and info
  SetPC White
  SetPos [-190 184] Label (List "L-System: :LSys :Name)
  SetPos [-190 -192] Label (List "Rule: "F: :Rule)
  SetPos [130 -192] Label List "Axiom: :Axiom
  SetPos [130 184] Label List "Order: :Order
  SetPos [130 170] Label List "Angle: :Angle
End

To Generate :String :Order
  If :Order < 1 [Output :String]
  Output Generate (ReWrite :String) :Order-1
End

To ReWrite :String
  # replace every F with rule
  Make "NewString "
  For (List "N 1 Count :String) [
    Make "Symbol Item :N :String
    If :Symbol = "F [Make "NewString Word :NewString :Rule] [
    Make "NewString Word :NewString :Symbol] ]
  Output :NewString
End

To Draw :String
  # render each symbol in string
  ForEach "Symbol :String [
    If :Symbol = "F [Forward :Step] [
    If :Symbol = "+ [Right :Angle] [
    If :Symbol = "- [Left :Angle] ] ] ]
End

To L_Sys1 :Order
  Make "Name "Snowflake_Curve
  Make "Scale 3
  Make "Angle 60
  Make "Rule "F-F++F-F
End

To L_Sys2 :Order
  Make "Name "Koch_Square
  Make "Scale 3
  Make "Angle 90
  Make "Rule "F-F+F+F-F
End

To L_Sys3 :Order
  Make "Name "Peano_Curve
  Make "Scale 3
  Make "Angle 90
  Make "Rule "F-F+F+F+F-F-F-F+F
End

To L_Sys4 :Order
  Make "Name "Quadratic_Koch_Curve
  Make "Scale 4
  Make "Angle 90
  Make "Rule "F+F-F-FF+F+F-F     # or add in extra central F
End

To L_Sys5 :Order
  Make "Name "Modified_Snowflake_Curve
  Make "Scale 4
  Make "Angle 60
  Make "Rule "F-F+F+F-F
End

To L_Sys6 :Order
  Make "Name "Modified_Snowflake_Curve2
  Make "Scale 4
  Make "Angle 60
  Make "Rule "F-F++FF--F+F
End

To L_Sys7 :Order
  Make "Name "Modified_Snowflake_Curve3
  Make "Scale 3
  Make "Angle 60
  Make "Rule "F-F++F++F--F--F+F
End

To Go :LSys :Order
  New
  Make "Screen 384 Make "Axiom "F
  Wash Home
  Run Word "L_Sys :LSys :Order
  Display :Lsys :Order SetPC Green
  Make "Step :Screen/Power :Scale :Order
  Make "DrawString Generate :Axiom :Order
  If :Order < 2 [Print :DrawString] [Print [printout supressed] ]
  SetPos List Minus :Screen/2 0 SetH 90
  PenDown Draw :DrawString PenUp
End

To GoX
  New
  Make "Screen 384 Make "Order 3 Make "Axiom "F
  For [LSys 1 7] [
    Wash Home Make "Step :Screen
    Run Word "L_Sys :LSys :Order
    Display :Lsys :Order
    Make "DrawString :Axiom
      For (List "Ord 1 :Order) [
      Make "DrawString ReWrite :DrawString
      SetPos List Minus :Screen/2 0 SetH 90
      Make "Step :Step / :Scale
      SetPC Item :Ord [3 1 6 2]
      SetPW Item (:Order+1)-:Ord [1 5 9 11]
  PenDown Draw :DrawString PenUp Wait 60] Wait 120]
End