RecursiveSquare.java

package org.teachingkidsprogramming.recipes.completed.section05recursion;

import org.teachingextensions.logo.Tortoise;
import org.teachingextensions.logo.utils.ColorUtils.PenColors;

public class RecursiveSquare
{
  public static void main(String[] args) throws Exception
  {
    Tortoise.show();
    Tortoise.getBackgroundWindow().setBackground(PenColors.Greens.DarkGreen);
    Tortoise.setPenColor(PenColors.Yellows.Gold);
    //  Set the speed to the fastest --#8
    Tortoise.setSpeed(10);
    //  Set the length to 100.0 --#1.1
    double length = 100.0;
    //  MakeASquare with the current length(recipe below) --#11.4
    makeASquare(length);
  }
  //
  //    Create the makeASquare recipe --#11.1 
  private static void makeASquare(double length)
  {
    //  If the current length is greater than 10 --#10.2
    if (length > 10)
    {
      //    Run the recipe moveToTheSquareStart with the current length  --#4.3
      moveToTheSquareStart(length);
      //
      //    Do the following 4 times --#7.1 
      for (int i = 0; i < 4; i++)
      {
        //      Move the Tortoise the current length  
        Tortoise.move(length);
        //      MakeASquare with the current length divided by 1.7 (recipe below)--#11.3  
        makeASquare(length / 1.7);
        //          If the current process count is less than 3 (HINT: use 'i') --#9
        if (i < 3)
        {
          //            Turn the tortoise 90 degrees to the right
          Tortoise.turn(90);
          //
        }
        //  End Repeat --#7.2  
      }
      //  MoveBackToCenter with the current length (recipe below)--#5.3 
      moveBackToCenter(length);
      //  Set the current length to the current length times two --#10.1
      length = length * 2;
    }
    //  End of makeASquare recipe
  }
  //  Create the moveToTheSquareStart recipe --#4.1
  private static void moveToTheSquareStart(double length)
  {
    //    Set the pen up for the tortoise --#1.2
    Tortoise.setPenUp();
    //    Move the tortoise the current length divided by two --#1.3
    Tortoise.move(length / 2);
    //    Turn the tortoise 90 degrees to the left --#2.1
    Tortoise.turn(-90);
    //    Move the tortoise the current length divided by two --#2.2
    Tortoise.move(length / 2);
    //    Turn the tortoise 180 degrees to the right --#3.1
    Tortoise.turn(180);
    //    Set the pen down for the tortoise --#3.2
    Tortoise.setPenDown();
    //  End of moveToTheSquareStart recipe --#4.2 
  }
  //
  //  Create the moveBackToCenter recipe 
  private static void moveBackToCenter(double length)
  {
    Tortoise.setPenUp();
    Tortoise.turn(90);
    Tortoise.move(length / 2);
    Tortoise.turn(90);
    Tortoise.move(length / 2);
    Tortoise.turn(180);
    Tortoise.setPenDown();
    //
  }
  //  End of moveBackToCenter recipe
}