MonoGame.Samples/Peer2PeerSample/PeerToPeerGame.cs

#region File Description
//-----------------------------------------------------------------------------
// PeerToPeerGame.cs
//
// Microsoft XNA Community Game Platform
// Copyright (C) Microsoft Corporation. All rights reserved.
//-----------------------------------------------------------------------------
#endregion

#region Using Statements
using System;

#if ANDROID
using Android.App;
#endif

using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Input.Touch;
using Microsoft.Xna.Framework.Net;

#endregion

namespace PeerToPeer
{
	/// <summary>
	/// Sample showing how to implement a simple multiplayer
	/// network session, using a peer-to-peer network topology.
	/// </summary>
	public class PeerToPeerGame : Microsoft.Xna.Framework.Game
	{
	#region Fields

		const int screenWidth = 1067;
		const int screenHeight = 600;
		const int maxGamers = 16;
		const int maxLocalGamers = 4;
		GraphicsDeviceManager graphics;
		SpriteBatch spriteBatch;
		SpriteFont font;
		KeyboardState currentKeyboardState;
		GamePadState currentGamePadState;
		TouchCollection currentTouchState;
		NetworkSession networkSession;
		PacketWriter packetWriter = new PacketWriter ();
		PacketReader packetReader = new PacketReader ();
		string errorMessage;
		Texture2D gamePadTexture;

	#endregion

	#region Initialization


        public PeerToPeerGame ()  
		{
			graphics = new GraphicsDeviceManager (this);
			
#if ANDROID || IPHONE
            graphics.IsFullScreen = true;
#else
			graphics.PreferredBackBufferWidth = screenWidth;
			graphics.PreferredBackBufferHeight = screenHeight;
			graphics.IsFullScreen = false;
#endif

			Content.RootDirectory = "Content";

			Components.Add (new GamerServicesComponent (this));
		}


		/// <summary>
		/// Load your content.
		/// </summary>
		protected override void LoadContent ()
		{
			spriteBatch = new SpriteBatch (GraphicsDevice);

			font = Content.Load<SpriteFont> ("Font");

#if ANDROID || IPHONE
			gamePadTexture = Content.Load<Texture2D>("gamepad.png");
			
			ThumbStickDefinition thumbStickLeft = new ThumbStickDefinition();
			thumbStickLeft.Position = new Vector2(10,400);
			thumbStickLeft.Texture = gamePadTexture;
			thumbStickLeft.TextureRect = new Rectangle(2,2,68,68);
			
			GamePad.LeftThumbStickDefinition = thumbStickLeft;
			
			ThumbStickDefinition thumbStickRight = new ThumbStickDefinition();
			thumbStickRight.Position = new Vector2(240,400);
			thumbStickRight.Texture = gamePadTexture;
			thumbStickRight.TextureRect = new Rectangle(2,2,68,68);
			
			GamePad.RightThumbStickDefinition = thumbStickRight;
#endif
		}


	#endregion

	#region Update


		/// <summary>
		/// Allows the game to run logic.
		/// </summary>
		protected override void Update (GameTime gameTime)
		{
			HandleInput ();

			if (networkSession == null) {
				// If we are not in a network session, update the
				// menu screen that will let us create or join one.
				UpdateMenuScreen ();
			} else {
				// If we are in a network session, update it.
				UpdateNetworkSession ();
			}

			base.Update (gameTime);
		}


		/// <summary>
		/// Menu screen provides options to create or join network sessions.
		/// </summary>
		void UpdateMenuScreen ()
		{
			if (IsActive) {
				if (Gamer.SignedInGamers.Count == 0) {
					// If there are no profiles signed in, we cannot proceed.
					// Show the Guide so the user can sign in.
					Guide.ShowSignIn (maxLocalGamers, false);
				} else if (IsPressed (Keys.A, Buttons.A)) {
					// Create a new session?
					CreateSession ();
                } else if (IsPressed(Keys.X, Buttons.X)) {
                    CreateLiveSession();
                }
                else if (IsPressed(Keys.Y, Buttons.Y))
                {
                    JoinSession(NetworkSessionType.PlayerMatch);
				} else if (IsPressed (Keys.B, Buttons.B)) {
					// Join an existing session?
					JoinSession (NetworkSessionType.SystemLink);
				}
			}
		}

        private void JoinLiveSession()
        {
            throw new NotImplementedException();
        }

        private void CreateLiveSession()
        {
            DrawMessage("Creating Live session...");

            try
            {
                networkSession = NetworkSession.Create(NetworkSessionType.PlayerMatch,
                            maxLocalGamers, maxGamers);

                HookSessionEvents();
                //networkSession.AddLocalGamer();
            }
            catch (Exception e)
            {
                errorMessage = e.Message;
            }
        }


		/// <summary>
		/// Starts hosting a new network session.
		/// </summary>
		void CreateSession ()
		{
			DrawMessage ("Creating session...");

			try {
				networkSession = NetworkSession.Create (NetworkSessionType.SystemLink, 
							maxLocalGamers, maxGamers);

				HookSessionEvents ();
				//networkSession.AddLocalGamer();
			} catch (Exception e) {
				errorMessage = e.Message;
			}
		}


		/// <summary>
		/// Joins an existing network session.
		/// </summary>
		void JoinSession (NetworkSessionType type)
		{
			DrawMessage ("Joining session...");

			try {
				// Search for sessions.
				using (AvailableNetworkSessionCollection availableSessions =
				NetworkSession.Find (type, 
						maxLocalGamers, null)) {
					if (availableSessions.Count == 0) {
						errorMessage = "No network sessions found.";
						return;
					}

					// Join the first session we found.
					networkSession = NetworkSession.Join (availableSessions [0]);

					HookSessionEvents ();
				}
			} catch (Exception e) {
				errorMessage = e.Message;
			}
		}


		/// <summary>
		/// After creating or joining a network session, we must subscribe to
		/// some events so we will be notified when the session changes state.
		/// </summary>
		void HookSessionEvents ()
		{
			networkSession.GamerJoined += GamerJoinedEventHandler;
			networkSession.SessionEnded += SessionEndedEventHandler;
		}


		/// <summary>
		/// This event handler will be called whenever a new gamer joins the session.
		/// We use it to allocate a Tank object, and associate it with the new gamer.
		/// </summary>
		void GamerJoinedEventHandler (object sender, GamerJoinedEventArgs e)
		{
			int gamerIndex = networkSession.AllGamers.IndexOf (e.Gamer);

			e.Gamer.Tag = new Tank (gamerIndex, Content, screenWidth, screenHeight);
		}


		/// <summary>
		/// Event handler notifies us when the network session has ended.
		/// </summary>
		void SessionEndedEventHandler (object sender, NetworkSessionEndedEventArgs e)
		{
			errorMessage = e.EndReason.ToString ();

			networkSession.Dispose ();
			networkSession = null;
		}


		/// <summary>
		/// Updates the state of the network session, moving the tanks
		/// around and synchronizing their state over the network.
		/// </summary>
		void UpdateNetworkSession ()
		{
			// Update our locally controlled tanks, and send their
			// latest position data to everyone in the session.
			foreach (LocalNetworkGamer gamer in networkSession.LocalGamers) {
				UpdateLocalGamer (gamer);
			}

			// Pump the underlying session object.
			networkSession.Update ();

			// Make sure the session has not ended.
			if (networkSession == null)
				return;

			// Read any packets telling us the positions of remotely controlled tanks.
			foreach (LocalNetworkGamer gamer in networkSession.LocalGamers) {
				ReadIncomingPackets (gamer);
			}
		}


		/// <summary>
		/// Helper for updating a locally controlled gamer.
		/// </summary>
		void UpdateLocalGamer (LocalNetworkGamer gamer)
		{
			// Look up what tank is associated with this local player.
			Tank localTank = gamer.Tag as Tank;

            if (localTank != null)
            {

                // Update the tank.
                ReadTankInputs(localTank, gamer.SignedInGamer.PlayerIndex);

                localTank.Update();

                // Write the tank state into a network packet.
                packetWriter.Write(localTank.Position);
                packetWriter.Write(localTank.TankRotation);
                packetWriter.Write(localTank.TurretRotation);

                // Send the data to everyone in the session.
                gamer.SendData(packetWriter, SendDataOptions.InOrder);
            }
		}


		/// <summary>
		/// Helper for reading incoming network packets.
		/// </summary>
		void ReadIncomingPackets (LocalNetworkGamer gamer)
		{
			// Keep reading as long as incoming packets are available.
			while (gamer.IsDataAvailable) {
				NetworkGamer sender;

				// Read a single packet from the network.
				gamer.ReceiveData (packetReader, out sender);

				// Discard packets sent by local gamers: we already know their state!
				if (sender.IsLocal)
					continue;

				// Look up the tank associated with whoever sent this packet.
				Tank remoteTank = sender.Tag as Tank;
                if (remoteTank != null)
                {

                    // Read the state of this tank from the network packet.
                    remoteTank.Position = packetReader.ReadVector2();
                    remoteTank.TankRotation = packetReader.ReadSingle();
                    remoteTank.TurretRotation = packetReader.ReadSingle();

                }
			}
		}


	#endregion

	#region Draw


		/// <summary>
		/// This is called when the game should draw itself.
		/// </summary>
		protected override void Draw (GameTime gameTime)
		{
			GraphicsDevice.Clear (Color.CornflowerBlue);

			if (networkSession == null) {
				// If we are not in a network session, draw the
				// menu screen that will let us create or join one.
				DrawMenuScreen ();
			} else {
				// If we are in a network session, draw it.
				DrawNetworkSession (gameTime);
			}

			base.Draw (gameTime);
		}


		/// <summary>
		/// Draws the startup screen used to create and join network sessions.
		/// </summary>
		void DrawMenuScreen ()
		{
			string message = string.Empty;

			if (!string.IsNullOrEmpty (errorMessage))
				message += "Error:\n" + errorMessage.Replace (". ", ".\n") + "\n\n";

			message += "A = create local session\n" +
            "X = create live session\n" +
            "Y = join live session\n" + 
			"B = join session";

			spriteBatch.Begin ();

			spriteBatch.DrawString (font, message, new Vector2 (61, 161), Color.Black);
			spriteBatch.DrawString (font, message, new Vector2 (60, 160), Color.White);

			spriteBatch.End ();
		}


		/// <summary>
		/// Draws the state of an active network session.
		/// </summary>
		void DrawNetworkSession (GameTime gameTime)
		{
			spriteBatch.Begin ();

			// For each person in the session...
			foreach (NetworkGamer gamer in networkSession.AllGamers) {
				// Look up the tank object belonging to this network gamer.
				Tank tank = gamer.Tag as Tank;

                if (tank != null)
                {
                    // Draw the tank.
                    tank.Draw(spriteBatch);

                    // Draw a gamertag label.
                    string label = gamer.Gamertag;
                    Color labelColor = Color.Black;
                    Vector2 labelOffset = new Vector2(100, 150);

                    if (gamer.IsHost)
                        label += " (host)";

                    // Flash the gamertag to yellow when the player is talking.
                    if (gamer.IsTalking)
                        labelColor = Color.Yellow;

                    spriteBatch.DrawString(font, label, tank.Position, labelColor, 0,
                        labelOffset, 0.6f, SpriteEffects.None, 0);
                }
			}
			
#if ANDROID || IPHONE
			GamePad.Draw(gameTime, spriteBatch);
#endif
			
			spriteBatch.End ();
		}


		/// <summary>
		/// Helper draws notification messages before calling blocking network methods.
		/// </summary>
		void DrawMessage (string message)
		{
			if (!BeginDraw ())
				return;

			GraphicsDevice.Clear (Color.CornflowerBlue);

			spriteBatch.Begin ();

			spriteBatch.DrawString (font, message, new Vector2 (161, 161), Color.Black);
			spriteBatch.DrawString (font, message, new Vector2 (160, 160), Color.White);

			spriteBatch.End ();

			EndDraw ();
		}


	#endregion

	#region Handle Input


		/// <summary>
		/// Handles input.
		/// </summary>
		private void HandleInput ()
		{
			currentKeyboardState = Keyboard.GetState ();
			currentGamePadState = GamePad.GetState (PlayerIndex.One);
			currentTouchState = TouchPanel.GetState();

			// Check for exit.
			if (IsActive && IsPressed (Keys.Escape, Buttons.Back)) {
				Exit ();
			}
			
			// Only test of Menu touches when networkSession is null
			if (networkSession == null) 
			{
				// Doing very very basic touch detection for menu
				if (currentTouchState.Count > 0) 
				{
					Console.WriteLine( string.Format("X:{0}, Y:{1}", currentTouchState[0].Position.X, currentTouchState[0].Position.Y ) );
					if ((currentTouchState[0].Position.X > 60 ) && (currentTouchState[0].Position.Y > 160 )
					&& (currentTouchState[0].Position.X < 220 ) && (currentTouchState[0].Position.Y < 190 ) )
					{
						CreateSession ();
					}
					
					if ((currentTouchState[0].Position.X > 60 ) && (currentTouchState[0].Position.Y > 200 )
					&& (currentTouchState[0].Position.X < 220 ) && (currentTouchState[0].Position.Y < 230 ) )
					{
						CreateLiveSession();
					}
					
					if ((currentTouchState[0].Position.X > 60 ) && (currentTouchState[0].Position.Y > 240 )
					&& (currentTouchState[0].Position.X < 220 ) && (currentTouchState[0].Position.Y < 270 ) )
					{
						JoinSession(NetworkSessionType.PlayerMatch);
					}
					
					if ((currentTouchState[0].Position.X > 60 ) && (currentTouchState[0].Position.Y > 280 )
					&& (currentTouchState[0].Position.X < 220 ) && (currentTouchState[0].Position.Y < 310 ) )
					{
						JoinSession(NetworkSessionType.SystemLink);
					}
				}
			}
			
		}


		/// <summary>
		/// Checks if the specified button is pressed on either keyboard or gamepad.
		/// </summary>
		bool IsPressed (Keys key, Buttons button)
		{
			return (currentKeyboardState.IsKeyDown (key) || 
			currentGamePadState.IsButtonDown (button));
		}


		/// <summary>
		/// Reads input data from keyboard and gamepad, and stores
		/// it into the specified tank object.
		/// </summary>
		void ReadTankInputs (Tank tank, PlayerIndex playerIndex)
		{
			// Read the gamepad.
			GamePadState gamePad = GamePad.GetState (playerIndex);

			Vector2 tankInput = gamePad.ThumbSticks.Left;
			Vector2 turretInput = gamePad.ThumbSticks.Right;

			// Read the keyboard.
			KeyboardState keyboard = Keyboard.GetState (playerIndex);

			if (keyboard.IsKeyDown (Keys.Left))
				tankInput.X = -1;
			else if (keyboard.IsKeyDown (Keys.Right))
				tankInput.X = 1;

			if (keyboard.IsKeyDown (Keys.Up))
				tankInput.Y = 1;
			else if (keyboard.IsKeyDown (Keys.Down))
				tankInput.Y = -1;

			if (keyboard.IsKeyDown (Keys.A))
				turretInput.X = -1;
			else if (keyboard.IsKeyDown (Keys.D))
				turretInput.X = 1;

			if (keyboard.IsKeyDown (Keys.W))
				turretInput.Y = 1;
			else if (keyboard.IsKeyDown (Keys.S))
				turretInput.Y = -1;

			// Normalize the input vectors.
			if (tankInput.Length () > 1)
				tankInput.Normalize ();

			if (turretInput.Length () > 1)
				turretInput.Normalize ();

			// Store these input values into the tank object.
			tank.TankInput = tankInput;
			tank.TurretInput = turretInput;
		}


	#endregion
	}
}