Battleship Mobile

Battleship Mobile

Marcus Degwert Marcus PflanzMartin Fleckner Christian ReibeholzMatthias Lauffer

Erfurt University of Applied Sciences

Sommersemester 2010

Battleships Mobile 2

Agenda

• Demo

• Konzept

• BlueTooth

• Verbindungsaufbau

• BT-Nutzung & Anbindung an das Gameplay

• Gameplay

• StateMachine

• Sound-Effekte

• Grafik


• Schiffeversenken, engl.: Battleship / Battleships

Konzept

• gegeneinander via BlueTooth spielbar


Bluetooth – verwendete Libaries

import javax.bluetooth.*;

import javax.microedition.io.Connector;

import javax.microedition.io.StreamConnection;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.util.Hashtable;

import java.util.Vector;


Bluetooth – Serverfinal class BTServer implements Runnable {

.

.

.

private static final UUID BATTLESHIPS_SERVER_UUID =

new UUID ("F0E0D0C0B0A000908070605040302010", false);

private LocalDevice localDevice;

private StreamConnectionNotifier notifier;

private ServiceRecord record;

private boolean isClosed;

private ClientProcessor processor;

private final Hashtable dataElements = new Hashtable ();

private StreamConnection connection;

private int state = 0;

.

.

.

}


Bluetooth – Serverpublic void run () {

…

localDevice = LocalDevice.getLocalDevice ();

if (!localDevice.setDiscoverable (DiscoveryAgent.GIAC)) {

…

}

StringBuffer url = new StringBuffer ("btspp://");

url.append ("localhost").append (':');

url.append (BATTLESHIPS_SERVER_UUID.toString ());

url.append (";name=Picture Server");

url.append (";authorize=false");

notifier = (StreamConnectionNotifier) Connector.open (url.toString ());

…

// ok, start processor now

processor = new ClientProcessor ();

…

this.connection = notifier.acceptAndOpen ();

…

input = this.connection.openInputStream();

output = this.connection.openOutputStream();

…

}


Bluetooth - Client

final class BTClient implements Runnable, DiscoveryListener {

…

private static final UUID BATTLESHIPS_SERVER_UUID =

new UUID ("F0E0D0C0B0A000908070605040302010", false);

private static final int DEVICE_SEARCH = 1;

private static final int SERVICE_SEARCH = 2;

private DiscoveryAgent discoveryAgent;

private Vector /* RemoteDevice */ devices = new Vector ();

private Vector /* ServiceRecord */ records = new Vector ();

private Hashtable base = new Hashtable ();

private LocalDevice localDevice;

…

}


Bluetooth - Clientpublic void run () {

…

this.localDevice = LocalDevice.getLocalDevice ();

discoveryAgent = this.localDevice.getDiscoveryAgent ();

…

this.EstablishConnection();

…

}

private synchronized void EstablishConnection () {

…

if (!searchDevices ()) {

return;

}

…

if (!searchServices ()) {

return;

}

…

if (this.Connect()) {

…

this.input = this.connection.openInputStream();

this.output = this.connection.openOutputStream();

…

}


Bluetooth - Client

private boolean searchDevices () {

…

discoveryAgent.startInquiry (DiscoveryAgent.GIAC, this);

…

}

private boolean searchServices () {

…

for (int i = 0; i < devices.size (); i++) {

RemoteDevice rd = (RemoteDevice) devices.elementAt (i);

…

searchIDs[i] = discoveryAgent.searchServices (attrSet, uuidSet, rd, this);

…

}

…

}


Bluetooth - Client

public boolean Connect() {

…

String[] urls = new String[this.records.size()];

for (int i = 0; i < this.records.size(); i++) { urls[i]=((ServiceRecord)(this.records.elementAt(i))).

getConnectionURL(ServiceRecord.NOAUTHENTICATE_NOENCRYPT, false);

}

…

this.connection = (StreamConnection)Connector.open(urls[i]);

…

}


BT-Nutzung & Anbindung an das Gameplay

• BlueTooth-Thread ruft öffentliche Methoden des Spielfeldes auf

• BlueTooth-Thread als Ausgangspunkt für das Gameplay

– Contra:

• keine saubere Trennung zwischen Netzwerk und Gameplay

– Pro:

• einfache (leicht verständliche) State-Machine

• sofortiges Senden/Empfangen von BT-Übertragungen

• keine Notwendigkeit für Mechanismen zur Thread-Synchronisierung



• Nachrichtenaufbau:

MessageType + SessionID + MessageID + X-Coord + Y-Coord

• MessageType - gibt an um welche Nachricht es sich handelt

• SessionID - einzigartige ID der aktuellen Sitzung

• MessageID - Sitzungsweite einzigartige ID dieser Nachricht

• X-Coord/Y-Coord - Koordinaten bei Beschuss/Beschussantwort (optional)


MessageTypes:

* BTK // other device is successfully set up and ready

* RDY // opponent has placed its ships and is waiting for other player

* STC // both players ready - client starts shooting

* STS // both players ready - server starts shooting

* QIT // player wants to leave the session or timeout

*

* SHT // shot at given coords

* WTR // shot with according sequence number dropped into water

* HIT // shot with according sequence number hit an enemy ship

* SNK // shot with according sequence number hit and destroyed a ship



BT-Nutzung & Anbindung an das Gameplaypublic boolean Shoot(Position pos)

{

// build the message

String message = SHOOT +

CONCAT +

this.sessionId +

CONCAT +

this.messageId +

CONCAT +

String.valueOf(pos.X()) +

CONCAT +

String.valueOf(pos.Y());

boolean result = this.SendMessage(message);

[...]



// -- read MessageType --

concatIndex = message.indexOf(CONCAT);

if (concatIndex == -1)

{

System.err.println("failed reading first CONCAT");

return;

}

messageType = message.substring(0, concatIndex);

System.out.print("reading message. type: " + messageType);


Soundeinbindung IProblem:

sequenzieller Ablauf im Programm

„Player“ blockiert weitere Interaktion

bis „Player“ in den Zustand „PREFETCHED“ über geht (END_OF_MEDIA, STOPPED)

Lösung:

Sound Hilfsklasse „BMESound“

welche einen neuen Thread startet

Implementiert das Interface „Runnable“

Jede Instanz von „BMESound“ erstellt neuen Thread

Paralleler Ablauf


Soundeinbindung IIimport javax.microedition.media.*;

public class BMESound implements Runnable{

private Player _player = null;

private String _file = null;

private String _type = null;

private boolean _bmesoundState = false;

private int _loopCount = 0;

Thread _t = null;

public BMESound(String file, String type, int lCount){}

public void start(){}

public void stop(){}

public void run(){}

}


Hit? Water

Finish?

n

DisplayResult

y

ShowWater (1sec)

WaitForShot Shot

Finish?

Placing

y

n

WeStart?Shoot

y n

Hit?

y

n

y

n


Grafik

• Darstellung des Spielfelds

• Darstellung der Schiffe

• Darstellung von Treffern / Wasserschüssen

• Probleme und Sorgenkinder:

- Skalierung des Spielfeldes für verschiedene Auflösungen

- kein "Fullscreen" (Toolleiste über dem Spielfeld sichtbar)

Battleship Mobile

Documents

Transcript of Battleship Mobile