GameGrid: Game programming with Java
Research project PHBern  
HomePrintJava-Online

16 Puzzle

 

A well-known puzzle game:

The 15 randomly set stones can be moved with the mouse. The goal of the game is to arrange the stones in the correct order

 

Run this example

 

Edit this example in the Online-Editor

  

Program code:

// NumberPuzzle.java

import ch.aplu.jgamegrid.*;

public class NumberPuzzle extends GameGrid
{
  public NumberPuzzle()
  {
    super(4, 4, 60, java.awt.Color.red, false);
    setSimulationPeriod(100);
    NumberStone[] stones = new NumberStone[15];
    for (int i = 0; i < 15; i++)
    {
      stones[i] = new NumberStone(i);
      addMouseListener(stones[i], GGMouse.lPress | GGMouse.lDrag | GGMouse.lRelease);
      addActor(stones[i], getRandomEmptyLocation());
    }
    doRun();
    show();
  }

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

// -----------------NumberStone.java-------------------------------------
class NumberStone extends Actor implements GGMouseListener
{
  private Location location;
  private Location lastLocation;
  private boolean isDragging = false;

  public NumberStone(int id)
  {
    super("sprites/stone" + id + ".gif");
  }

  public void act()
  {
    if (isDragging)
    {
      setLocation(lastLocation);
      // Blinking
      if (isVisible())
        hide();
      else
        show();
    }
  }

  private boolean isFreeNeighbourCell(Location location)
  {
    GameGrid gg = gameGrid;
    Location[] neighbour = new Location[4];
    neighbour[0] = new Location(location.x, location.y - 1);  // NORTH
    neighbour[1] = new Location(location.x - 1, location.y);  // WEST
    neighbour[2] = new Location(location.x, location.y + 1);  // SOUTH
    neighbour[3] = new Location(location.x + 1, location.y);  // EAST
    for (int i = 0; i < 4; i++)
    {
      if (gg.isInGrid(neighbour[i]) && gg.getNumberOfActorsAt(neighbour[i]) == 0)
        return true;
    }
     return false;
  }

  public boolean mouseEvent(GGMouse mouse)
  {
    GameGrid gg = gameGrid;
    location = gg.toLocationInGrid(mouse.getX(), mouse.getY());
    Actor actor = gg.getOneActorAt(location);
    if (actor != null && // Cell not empty
      isFreeNeighbourCell(location) &&  // One free cell to move to
      actor == this && // Restrict to current instance
      mouse.getEvent() == GGMouse.lPress)
    {
      isDragging = true;
      lastLocation = location.clone();
    }
    if (isDragging && mouse.getEvent() == GGMouse.lRelease)
    {
      setLocation(lastLocation);
      isDragging = false;
      show();
    }
    if (isDragging && mouse.getEvent() == GGMouse.lDrag)
    {
      if (gg.getNumberOfActorsAt(location) < 1) // Cell not occupied
        lastLocation = location.clone();
    }
    return false;  // Don't consume
  }
}