Turtlegrafik

Multiple Turtles

With the constructor Turtle() more than one Turtle-object can be generated.
Turtle joe = new Turtle(); generates the first Turtle in a window. If afterwards a second Turtle is generated with Turtle luka = new Turtle(); it will run in a second window and not in the same as the first one. It is possible to generate up to 20 Turtles in different windows.

// Tu15.java

import ch.aplu.turtle.*;
import java.awt.Color;

public class  Tu15
{
  public Tu15()
  {
    Turtle joe = new Turtle();
    Turtle luka = new Turtle(joe); //erzeugt luka im joe's-Fenster
    luka.setColor(Color.red);
    luka.setPenColor(Color.green);
    joe.setPos(-100, -100);
    luka.setPos(50,-100);

    for (int i = 0; i < 5; i++)
    {
      square(joe);
      joe.forward(40);
      square(luka);
      luka.forward(40);
    }
  }

  void square(Turtle t)
  {
    for (int i = 0; i < 4; i++)
    {
      t.forward(40);
      t.right(90);
    }
  }

  public static void main(String[] args)
  {
    new Tu15();
  }
}

With Turtle luka = new Turtle(joe); a second Turtle is generated in the window of the first one. So luka is now inside joe's window. In this example a constructor with a parameter is used: Turtle(Turtle other Turtle). This allows both Turtles to run in one window.

// Tu16.java

import ch.aplu.turtle.*;
import java.awt.Color;

public class  Tu16
{
  public Tu16()
  {
    Turtle joe = new Turtle();
    Turtle lea = new Turtle(joe, Color.red);
    Turtle sara = new Turtle(joe, Color.green);
    joe.setPos(-135, -50);
    lea.setPos(-10, -50);
    sara.setPos(115, -50);
    sara.setPenColor(Color.green);
    lea.setPenColor(Color.red);
    for (int i = 0; i < 9; i++)
    {
      segment(joe);
      segment(lea);
      segment(sara);
    }
  }

  void segment(Turtle t)
  {
    t.forward(140);
    t.right(160);
  }

  public static void main(String[] args)
  {
    new Tu16();
  }
}