Tutorial2:NetworkedWackadot

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public Wackadot()
{
   setNumberOfPlayers(2);
}
 

Line 4: the default number of players is always one. Making the default number of players more than one will allow them to change how many players should connect. The player who establishes the game name is the one who determines how many should connect before the game begins. For all players who connect to an established game name, the number of players field is not used so long as it is more than 1 (when it is one-player, the game does not connect to the server).

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public void advance()
{
   if(timeLeft>0)
   {
      Location2D mouse=
         getMouse2D(0);
      dot.setLocation(mouse);
      handleCollisions();
   }
}
 

Line 148: Notice that the getMouse2D method now has the argument zero. This means that the player returned should be the first player. Absent any arguments, the current player is returned from the getPlayer method.

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public class Wackadot extends Game
{
  private Sprite[] dot;>
  private Sprite redDot;

   ...

  private void makeSprites()
  {
     dot=new Sprite[getNumberOfPlayers()];
     for(int i=0; i<dot.length; i++)
     {
        dot[i]=new OvalSprite(1, 1);
        dot[i].setScale(0.1);
        dot[i].setLocation(0.5, 0.5);
        dot[i].setColor(getColor("red"));    		
     }

     ...    	
  }

  ...

  private void handleCollisions()
  {
     /* need to fill in this later */
  }

  public void advance()
  {
     if(timeLeft>0)
     {
        for(int i=0; i<dot.length; i++)
        {
           Location2D mouse=
                    getMouse2D(i);
           dot[i].setLocation(mouse);
        }
        handleCollisions();
     }
  }

  ...
 
}

Line 14: makes the variable dot an array of Sprites. Originally it was a single Sprite. Only insert the [] between the Sprite and the dot. After adding this line, you will see many errors. These errors will be fixed when you complete this table.

Line ...: indicates code left out. Do not copy the ellipses.

Line 51: makes the array of dots capable of holding as many Sprites as there are players. You'll need to change the existing code that initialized dot to be like the new line 51 that initializes dot. Also, the lines 54-57 existed in the code, but without the [i] part. You'll need to insert the [i] part and the surrounding for loop.

Line 51-58: iterates over the positions in the array initializing each element to be a red dot.

Line ...: indicates code left out. Do not copy the ellipses.

Line 113: the handleCollisions method needs many modifications. It's better to make many simple modifications and test them individually than to make one complex modification. We'll make the handleCollisions modifications in later steps once we have made sure everything else still works. Therefore, remove most of the lines of handleCollisions and just leave in a single comment.

Line ...: indicates code left out. Do not copy the ellipses.

Lines 120-125: lets player i control dot i. The variable i will iterate over the player indices. You need to only insert the for loop and change the 0 in getPlayer to i and insert the [i] beside dot.

Line ...: indicates code left out. Do not copy the ellipses.

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private void handleCollisions()
{
   for(int i=0; i<dot.length; i++)
      handleCollisions(i);
}
      
private void handleCollisions(int playerIndex)
{
   if(dot[playerIndex].intersects(blueDot))
   {
      repositionRandomly(blueDot);
      if(dot[playerIndex].getColor().equals(getColor("blue")))
      {
         dot[playerIndex].setColor(getColor("red"));
         score++;
      }
      else
      {
         score--;
      }
      updateScore();
   }
   if(dot[playerIndex].intersects(redDot))
   {
      repositionRandomly(redDot);
      if(dot[playerIndex].getColor().equals(getColor("red")))
      {
         dot[playerIndex].setColor(getColor("blue"));
         score++;
      }
      else
      {
         score--;
      }
      updateScore();
   }
}
 

Lines 113-114: handleCollisions now calls the parameterized handleCollisions for each player declared on line 7. This should now be the only code in this method.

Lines 117-147: instead of checking for collision with the single dot in the one player version, this checks for collision with the player indicated by the parameter playerIndex. This should be the only code in this method. Notice that this is the changed code from the code which is commented out in table C.