Hacked in networked objects. Without Zay-ES and without Sim-ethereal,

it's all pretty hacky.  I was trying to make an ES-free example but it's hard.

Author: pspeed42

sim-eth-basic/assets/Models/fighter.j3o

@@ -90,6 +90,10 @@ public ConnectionState( AppState parent, String host, int port ) {
         this.host = host; 
         this.port = port;
     }
+    
+    public int getClientId() {
+        return client.getClient().getId();
+    }
 
     public <T extends ClientService> T getService( Class<T> type ) {
         return client.getService(type);

sim-eth-basic/assets/Textures/ship1.png

@@ -36,8 +36,10 @@
 
 package example;
 
+import org.slf4j.*;
+
 import com.jme3.app.Application;
-import com.jme3.math.ColorRGBA;
+import com.jme3.math.*;
 
 import com.simsilica.event.EventBus;
 import com.simsilica.lemur.GuiGlobals;
@@ -46,6 +48,7 @@
 
 import example.net.GameSessionListener;
 import example.net.client.GameSessionClientService;
+import example.view.ModelViewState;
 import example.view.PlayerMovementState;
 import example.view.SkyState;
 import example.view.SpaceGridState;
@@ -58,12 +61,20 @@
  */
 public class GameSessionState extends CompositeAppState {
 
+    static Logger log = LoggerFactory.getLogger(GameSessionState.class);
+
     private GameSessionObserver gameSessionObserver = new GameSessionObserver();
 
+    // Temporary reference FIXME
+    private PlayerMovementState us;
+    private int clientId;
+    private int shipId;
+
     public GameSessionState() {
         // add normal states on the super-constructor
         super(new MessageState(),
               new SkyState(),
+              new ModelViewState(),
               new PlayerMovementState(),
               new SpaceGridState(GameConstants.GRID_CELL_SIZE, 10, new ColorRGBA(0.8f, 1f, 1f, 0.5f)) 
               //new SpaceGridState(2, 10, ColorRGBA.White) 
@@ -74,6 +85,10 @@ public GameSessionState() {
         addChild(new InGameMenuState(false), true);
     }
 
+    public int getShipId() {
+        return shipId;
+    }
+ 
     public void disconnect() {
         // Remove ourselves
         getStateManager().detach(this);
@@ -93,7 +108,12 @@ protected void initialize( Application app ) {
 
         InputMapper inputMapper = GuiGlobals.getInstance().getInputMapper();
         inputMapper.activateGroup(MainGameFunctions.IN_GAME);
-        
+ 
+        // Temporary FIXME
+        clientId = getState(ConnectionState.class).getClientId();
+        us = getState(PlayerMovementState.class);
+        shipId = getState(ConnectionState.class).getService(GameSessionClientService.class).getPlayerObject();
+        log.info("Player object:" + shipId);
     }
 
     @Override   
@@ -127,12 +147,24 @@ protected void onDisable() {
      *  Notified by the server about game-session related events.
      */
     private class GameSessionObserver implements GameSessionListener {
+ 
+        @Override
         public void playerJoined( int clientId, String playerName, int shipId ){
-            getState(MessageState.class).addMessage("> " + playerName + " has joined.", ColorRGBA.Yellow);  
+            getState(MessageState.class).addMessage("> " + playerName + " has joined.", ColorRGBA.Yellow);
         }
 
+        @Override
         public void playerLeft( int clientId, String playerName, int shipId ) {
             getState(MessageState.class).addMessage("> " + playerName + " has left.", ColorRGBA.Yellow);  
         }
+        
+        @Override
+        public void updateObject( int objectId, Quaternion orientation, Vector3f pos ) {
+            //System.out.println("updateObject(" + objectId + ", " + orientation + ", " + pos + ")");
+            //System.out.println("   dir:" + orientation.mult(Vector3f.UNIT_Z));
+            if( objectId == shipId ) {
+                us.updatePlayerPosition(pos.x, pos.y, pos.z);
+            } 
+        }
     }
 }

sim-eth-basic/src/main/java/example/ConnectionState.java

@@ -49,6 +49,11 @@
  */
 public interface GameSession {
 
+    /**
+     *  Returns the ID of the player object.
+     */
+    public int getPlayerObject();
+ 
     /**
      *  Sends information to the game back end about the current
      *  movement state of the player from user input.  Because this

sim-eth-basic/src/main/java/example/GameSessionState.java

@@ -36,6 +36,7 @@
 
 package example.net;
 
+import com.jme3.math.*;
 import com.jme3.network.service.rmi.Asynchronous;
 
 /**
@@ -52,6 +53,15 @@ public interface GameSessionListener {
     @Asynchronous   
     public void playerJoined( int clientId, String playerName, int shipId );
 
+    /**
+     *  Temporary call that updates a ship's position.  This is the naive
+     *  way to do networking where everything is just blasted out all the time.
+     *  We'll at least use UDP to be timely... which means we'll also end up
+     *  dropping packets.
+     */
+    @Asynchronous(reliable=false)   
+    public void updateObject( int bodyId, Quaternion orientation, Vector3f pos );   
+    
     /**
      *  Called when an existing player has left the game.
      */   

sim-eth-basic/src/main/java/example/net/GameSession.java

@@ -70,6 +70,11 @@ public class GameSessionClientService extends AbstractClientService
     public GameSessionClientService() {
     }
 
+    @Override
+    public int getPlayerObject() {
+        return getDelegate().getPlayerObject();
+    }
+    
     @Override
     public void move( Quaternion dir, Vector3f thrust ) {
         if( log.isTraceEnabled() ) {
@@ -150,6 +155,13 @@ public void playerJoined( int clientId, String playerName, int shipId ) {
             }
         }
 
+        @Override   
+        public void updateObject( int bodyId, Quaternion orientation, Vector3f pos ) {
+            for( GameSessionListener l : listeners ) {
+                l.updateObject(bodyId, orientation, pos);
+            }
+        }   
+        
         @Override   
         public void playerLeft( int clientId, String playerName, int shipId  ) {
             log.debug("playerLeft(" + clientId + ", " + playerName + ")");

sim-eth-basic/src/main/java/example/net/GameSessionListener.java

@@ -55,9 +55,12 @@
 
 import com.simsilica.event.EventBus;
 import com.simsilica.sim.GameSystemManager;
+import com.simsilica.sim.SimTime;
 
 import example.net.GameSession;
 import example.net.GameSessionListener;
+import example.sim.Body;
+import example.sim.PhysicsListener;
 import example.sim.ShipDriver;
 import example.sim.SimplePhysics;
 
@@ -82,6 +85,8 @@ public class GameSessionHostedService extends AbstractHostedConnectionService {
     private AccountObserver accountObserver = new AccountObserver();
 
     private List<GameSessionImpl> players = new CopyOnWriteArrayList<>();
+    // FIXME: remove array when we get rid of the naive listener
+    private volatile GameSessionImpl[] playersArray = null;
 
     public GameSessionHostedService( GameSystemManager gameSystems ) {
 
@@ -118,6 +123,7 @@ public void start() {
         if( physics == null ) {
             throw new RuntimeException("GameSessionHostedService requires a SimplePhysics system.");
         }
+        physics.addPhysicsListener(new NaivePhysicsSender());
     }
 
     @Override
@@ -131,8 +137,13 @@ public void startHostingOnConnection( HostedConnection conn ) {
         // Expose the session as an RMI resource to the client
         RmiRegistry rmi = rmiService.getRmiRegistry(conn);
         rmi.share(session, GameSession.class);
-        
-        players.add(session);
+ 
+        // FIXME: remove sync when we get rid of the naive listener
+        synchronized( players ) {       
+            players.add(session);
+            playersArray = null;
+        }
+        session.initialize();
 
         // Notify all of our sessions
         for( GameSessionImpl player : players ) {
@@ -150,7 +161,11 @@ public void stopHostingOnConnection( HostedConnection conn ) {
 
         GameSessionImpl session = getGameSession(conn);
         if( session != null ) {
-            players.remove(session);
+            // FIXME: remove sync when we get rid of the naive listener
+            synchronized( players ) {
+                players.remove(session);
+                playersArray = null;
+            }
 
             // Notify all of our sessions
             for( GameSessionImpl player : players ) {
@@ -170,6 +185,24 @@ public void stopHostingOnConnection( HostedConnection conn ) {
             // when we've stopped hosting our service on it.
         }   
     }
+    
+    private GameSessionImpl[] getPlayerArray() {
+        // Copy the reference so we're sure we are returning
+        // what we null-check.
+        GameSessionImpl[] result = playersArray;
+        if( result != null ) {
+            return result;
+        }
+        
+        synchronized(players) {
+            // Check again
+            if( playersArray == null ) {
+                playersArray = new GameSessionImpl[players.size()];
+                playersArray = players.toArray(playersArray);
+            }
+            return playersArray;
+        }
+    }
 
     private class AccountObserver {
 
@@ -183,6 +216,28 @@ public void onPlayerLoggedOff( AccountEvent event ) {
             stopHostingOnConnection(event.getConnection());   
         }
     }
+
+    /**
+     *  A naive implementation of a physics listener that just blasts
+     *  everything out to all of the clients over UDP.
+     */
+    private class NaivePhysicsSender implements PhysicsListener {
+    
+        public void beginFrame( SimTime time ) {
+        }
+ 
+        public void updateBody( Body body ) {
+            // Lots of garbage created here but it's temporary
+            Quaternion orientation = body.orientation.toQuaternion();
+            Vector3f pos = body.pos.toVector3f();
+            for( GameSessionImpl session : getPlayerArray() ) {
+                session.updateObject(body.bodyId, orientation, pos);   
+            }
+        }
+    
+        public void endFrame( SimTime time ) {
+        }         
+    }
 
     /**
      *  The connection-specific 'host' for the GameSession.
@@ -202,11 +257,38 @@ public GameSessionImpl( HostedConnection conn ) {
             this.bodyId = physics.createBody(shipDriver);
         }
 
+        public void initialize() {
+        }
+ 
         public void close() {
             // Remove out physics body
             physics.removeBody(bodyId);
         }
 
+        @Override
+        public int getPlayerObject() {
+
+            // Cheat and tell this player about the other players by
+            // sending late join messages
+            // FIXME - this is a big hack because we're using it as the side-effect
+            // of a remote get.                       
+            for( GameSessionImpl player : players ) {
+                playerJoined(player);          
+            }   
+
+            return bodyId;
+        }
+
+        @Override   
+        public void move( Quaternion rotation, Vector3f thrust ) {
+            if( log.isTraceEnabled() ) {
+                log.trace("move(" + rotation + ", " + thrust + ")");
+            }
+            
+            // Need to forward this to the game world
+            shipDriver.applyMovementState(rotation, thrust);
+        }
+        
         public void playerJoined( GameSessionImpl player ) {            
             getCallback().playerJoined(player.conn.getId(),
                                        AccountHostedService.getPlayerName(player.conn),
@@ -219,6 +301,10 @@ public void playerLeft( GameSessionImpl player ) {
                                      player.bodyId);
         } 
 
+        public void updateObject( int bodyId, Quaternion orientation, Vector3f pos ) {
+            getCallback().updateObject(bodyId, orientation, pos);
+        }   
+ 
         protected GameSessionListener getCallback() {
             if( callback == null ) {
                 RmiRegistry rmi = rmiService.getRmiRegistry(conn);
@@ -230,15 +316,6 @@ protected GameSessionListener getCallback() {
             return callback;
         } 
 
-        @Override   
-        public void move( Quaternion rotation, Vector3f thrust ) {
-            if( log.isTraceEnabled() ) {
-                log.trace("move(" + rotation + ", " + thrust + ")");
-            }
-            
-            // Need to forward this to the game world
-            shipDriver.applyMovementState(rotation, thrust);
-        }
     }    
 }
 

sim-eth-basic/src/main/java/example/net/client/GameSessionClientService.java

@@ -65,11 +65,21 @@ public void applyMovementState( Quaternion orientation, Vector3f thrust ) {
     } 
 
     private double applyThrust( double v, double thrust, double tpf ) {
-        if( v < thrust ) {
+        if( thrust > 0 ) {
+            // Accelerate
             v = Math.min(thrust, v + pickup * tpf);
-        } else if( v > thrust ) {
-            v = Math.max(-thrust, v - pickup * tpf);
-        }   
+        } else if( thrust < 0 ) {
+            // Decelerate
+            v = Math.max(thrust, v - pickup * tpf);
+        } else {
+            if( v > 0 ) {
+                // Fall to zero
+                v = Math.max(0, v - pickup * tpf);
+            } else {
+                // Rist to zero
+                v = Math.min(0, v + pickup * tpf);
+            }
+        }
         return v;
     }