flocking3d.java

来自「一个模拟鸟群飞行的3D程序」· Java 代码 · 共 98 行

// Flocking3D.java
// Andrew Davison, April 2005, [e-mail]
// Sirinart Sakarin, March 2003, [e-mail]

/* This program illustrates flocking boids.

   Boids follow simple rules that govern their movement.
   When these simple rules are combine at run-time, complex
   behaviours emerge without the need for explicit programming.

   Our boid behaviours include:
      * perching occasionally
      * avoiding obstacles
      * staying within the scene volume
      * not moving faster than a set maximum speed
      * Reynold's velocity rules for:
          - cohesion
          - separation
          - alignment
      * the Predators chase (and eat) the prey boids
      * the prey boids try to out-run the predators

   Some coding ideas came from the Boids Demo by Anthony Steed 
   ([e-mail]) at 
    http://www.cs.ucl.ac.uk/staff/A.Steed/3ddesktop

   Some algorithm ideas came from the Boids pseudocode paper by 
   Conrad Parker ?? at
   http://www.vergenet.net/~conrad/boidsList/pseudocode.html
*/

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;


public class Flocking3D extends JFrame
{
  // constants for the numbers of predators, prey, and obstacles
  private static final int NUM_PREDATORS = 40;
  private static final int NUM_PREY = 160;
  private static final int NUM_OBSTACLES = 20;


  public Flocking3D(String[] args) 
  {
    super("Flocking Predator and Prey Boids");

    int numPreds = NUM_PREDATORS;
    int numPrey = NUM_PREY;
    int numObstacles = NUM_OBSTACLES;

    // simple extraction of command line args.
    if (args.length >= 1) {
      try 
      { numPreds = Integer.parseInt( args[0] ); 
        numPrey = numPreds;    // same number of predators and prey
      }
      catch(NumberFormatException e)
      { System.out.println("Illegal number of predators"); }
    }

    if (args.length >= 2) {
      try 
      { numPrey = Integer.parseInt( args[1] ); }
      catch(NumberFormatException e)
      { System.out.println("Illegal number of prey"); }
    }

    if (args.length == 3) {
      try 
      { numObstacles = Integer.parseInt( args[2] ); }
      catch(NumberFormatException e)
      { System.out.println("Illegal number of obstacles"); }
    }

    Container c = getContentPane();
    c.setLayout( new BorderLayout() );
    WrapFlocking3D w3d = 
		new WrapFlocking3D(numPreds, numPrey, numObstacles);
    c.add(w3d, BorderLayout.CENTER);

    setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
    pack();
    setResizable(false);    // fixed size display
    setVisible(true);
  } // end of Flocking3D()


// -----------------------------------------

  public static void main(String[] args)
  { new Flocking3D(args); }

} // end of Flocking3D class