Client and Server (DirectX)

Transcription

1 Client and Server (DirectX) Vishnu Kotrajaras Server scalability Your game can handle more players at a time (Over internet, most peer-topeer can only handle about 6 players) All depend on server power Too many people-> just upgrade server (client does not have to do much configuration) 1

2 Firewalls Peer-to-peer needs many holes in the firewall, but firewalls allow only a few ports to open Client/server only needs one port open Simplicity Clients only worry about themselves Server can be left with a simple interface Server can run on many OS 2

3 IDirectPlay8Server Interface Initialize COM with CoInitialize() Then it must be created with CoCreateInstance() The methods are like what you ve seen for peers IDirectPlay8Server functions (1) Initialize- sets up the interface to receive messages for connections Close- disconnects and closes the server from the current session Host- creates the session in which clients can connect 3

4 IDirectPlay8Server functions (2) SendTo- transmits data to one or many players within the session EnumServiceProviders- enumerates service providers available to the server SetApplicationDesc- changes particular application settings for an existing session CreateGroup- creates a new group to which players can be added DestroyGroup IDirectPlay8Server functions (3) AddPlayerToGroup RemovePlayerFromGroup GetGroupInfo GetClientInfo DestroyClient GetClientAddress- get DPlay address string for a client 4

5 IDirectPlay8Server functions (4) GetLocalHostAddresses- get DPlay address used to host the local server GetSendQueueInfo- monitors the send message queue for a particular client GetConnectionInfo- gets info about the connection with a particular client GetApplicationDesc After CoCreateInstance() of server Init IDirectPlay8Server Message Handler (all messages will be sent here) HRESULT Initialize( PVOID Const pvusercontext, PFNDPNMESSAGEHANDLER pfn, DWORD dwflags ); Pointer to message handler The only flag is DPNINITIALIZE_DISABLEPARAMVAL Disable parameter validation, but normally we won t use it 5

6 After Initialize() Set up device address (for the host) Set the address service provider The code is very similar to the code for peers hosting 1. Set up the server info with SetServerInfo() 2. Set up application description with the DPN_APPLICATION_DESC data structure 3. Set up the address to handle things with AddComponent() 4. Call the Host() function 6

7 SetServerInfo() Server info, e.g.name HRESULT SetServerInfo( const DPN_PLAYER_INFO *const pdpnplayerinfo, PVOID const pvasyncontext, User context (opt) DPNHANDLE *const phasynchandle, const DWORD dwflags ) DPNSETSERVERINFO_SYNC ->process synchronously // // Setup our player information // DXUtil_ConvertGenericStringToWide( wszservername, "DPChat Server" ); ZeroMemory( &dpplayerinfo, sizeof(dpn_player_info) ); dpplayerinfo.dwsize = sizeof(dpn_player_info); dpplayerinfo.dwinfoflags = DPNINFO_NAME; dpplayerinfo.pwszname = wszservername; // Set us up to be non-asynchronous if( FAILED( hreturn = g_pdpserver- >SetServerInfo( &dpplayerinfo, NULL, NULL, DPNSETSERVERINFO_SYNC ) ) ) { MessageBox( hwindow, "Failed to SetServerInfo()", "Unknown Error", MB_ICONERROR ); return -1; 7

8 Set up DPN_APPLICATION_DESC Use just like you used peers, but dwflags change to DPNSESSION_CLIENT_SERVER // Setup the application description DXUtil_ConvertGenericStringToWide( wszsessionname, "DPChat Session" ); ZeroMemory( &dnappdesc, sizeof(dpn_application_desc) ); dnappdesc.dwsize = sizeof(dpn_application_desc); dnappdesc.guidapplication = GUID_CHATSERVER; dnappdesc.pwszsessionname = wszsessionname; dnappdesc.dwmaxplayers = MAX_PLAYERS; dnappdesc.dwflags = DPNSESSION_CLIENT_SERVER; 8

9 Set up the address Need to add server s host port number Clients communicate through here // Tell the port number // Add port number to host address // hreturn = g_pdeviceaddress- >AddComponent(DPNA_KEY_PORT,&dwPort,sizeof(DWORD),DPNA_ DATATYPE_DWORD); if( hreturn!= S_OK ) { MessageBox( hwindow, "Failed to AddComponent()", "hrhostgame()", MB_ICONERROR ); return -1; Host() HRESULT Host( const DPN_APPLICATION_DESC *const pdnappdesc, ); How many devices in the second parameter IDirectPlay8Address **const prgdeviceinfo, const DWORD cdeviceinfo, const DPN_SECURITY_DESC *const pdpsecurity, The app.desc you created Device you just added port number const DPN_SECURITY_CREDENTIALS *const pdpcredentials, VOID *const pvplayercontext, const DWORD dwflags Hosting flags Optional user context Not used by DirectX8 9

10 hreturn = g_pdpserver->host( &dnappdesc, &g_pdeviceaddress, 1, NULL, NULL, NULL, NULL ); if( FAILED( hreturn ) ) { MessageBox( hwindow, "Failed to Host()", "DirectPlay Error", MB_ICONERROR ); return -1; Managing Players When a player connects to your game, he passes you a creation message You need to add him to your table of active players 10

11 HRESULT hrcreateplayer( PVOID pvusercontext, PVOID pmsgbuffer ) { HRESULT hreturn = S_OK; PDPNMSG_CREATE_PLAYER pcreateplayermsg; char strname[256]; char szoutput[256]; DWORD dwsize = 0; DPN_PLAYER_INFO *pdpplayerinfo = NULL; int i; // Get a Create Message pointer to the buffer pcreateplayermsg = (PDPNMSG_CREATE_PLAYER)pMsgBuffer; // Get the peer info and extract its name hreturn = g_pdpserver->getclientinfo( pcreateplayermsg->dpnidplayer, pdpplayerinfo, &dwsize, 0 ); if( FAILED(hReturn) && hreturn!= DPNERR_BUFFERTOOSMALL ) { if( hreturn == DPNERR_INVALIDPLAYER ) { vshowtext(hlb_output,"adding Ourselves"); hreturn = -1; GET SIZE else { pdpplayerinfo = (DPN_PLAYER_INFO*) new BYTE[ dwsize ]; ZeroMemory( pdpplayerinfo, dwsize ); pdpplayerinfo->dwsize = sizeof(dpn_player_info); hreturn = g_pdpserver->getclientinfo( pcreateplayermsg- >dpnidplayer, pdpplayerinfo, &dwsize, 0 ); if( FAILED(hReturn) ) { USE THE SIZE THAT WE GET FOR THE 2 ND CALL 11

12 HRESULT GetClientInfo( const DPNID dpnid, // belongs to the client that we want info DPN_PLAYER_INFO *const pdpnplayerinfo, //this will hold the soon- to- //be-retrieved player info DWORD *const pdwsize, //size of the information retrieved. //If the buffer size is too small, //DPNERR_BUFFERTOOSMALL is returned const DWORD dwflags //DPNINFO_NAME or DPNINFO_DATA ); else { >pwszname ); >dpnidplayer; vshowtext(hlb_output,"error Getting Client Info"); hreturn = -1; EnterCriticalSection( &g_csmodifyplayer ); // Convert player name to ANSI DXUtil_ConvertWideStringToGeneric( strname, pdpplayerinfo- // Add player to list for( i = 0 ; i < MAX_PLAYERS ; i++ ) { if(!playerinfo[i].bactive ) { PlayerInfo[i].bActive = 1; PlayerInfo[i].dpnidPlayer = pcreateplayermsg- strcpy(playerinfo[i].szplayername,strname); break; // Check if no free slot found if( i == MAX_PLAYERS ) { 12

13 vshowtext(hlb_output,"no free slots in game!"); // Check if we are adding ourselves else if( pdpplayerinfo->dwplayerflags & DPNPLAYER_LOCAL ) { g_dpnidlocalplayer = pcreateplayermsg- >dpnidplayer; sprintf(szoutput,"<slot%d> Added Ourselves",i); vshowtext(hlb_output,szoutput); else { sprintf(szoutput,"<slot%d><%s> Is In The Game",i,strName); vshowtext(hlb_output,szoutput); SAFE_DELETE_ARRAY( pdpplayerinfo ); way // Update the number of active players in a thread safe if( i!= MAX_PLAYERS ) InterlockedIncrement( &g_lnumberofactiveplayers ); LeaveCriticalSection( &g_csmodifyplayer ); return hreturn; 13

14 Destroy Player Must check for DPN_MSGID_DESTROY_PLAYER CALL hrdestroyplayer() to process it HRESULT hrdestroyplayer( PVOID pvusercontext, PVOID pmsgbuffer ) { PDPNMSG_DESTROY_PLAYER pdestroyplayermsg; HRESULT hreturn = S_OK; int i; char szoutput[256]; // Get a Destroy Message pointer to the buffer pdestroyplayermsg = (PDPNMSG_DESTROY_PLAYER)pMsgBuffer; // Update the number of active players in a thread safe way InterlockedDecrement( &g_lnumberofactiveplayers ); EnterCriticalSection( &g_csmodifyplayer ); // Remove Player from list Use this, so that we can find the player s ID 14

15 for( i = 0 ; i < MAX_PLAYERS ; i++ ) { if( PlayerInfo[i].bActive ) { if( PlayerInfo[i].dpnidPlayer == pdestroyplayermsg->dpnidplayer ) { PlayerInfo[i].bActive = 0; sprintf(szoutput,"<slot%d><%s> Left The Game",i,PlayerInfo[i].szPlayerName); vshowtext(hlb_output,szoutput); break; LeaveCriticalSection( &g_csmodifyplayer ); return(hreturn); Receiving messages from DWORD dwtype; DWORD dwsize; client case DPN_MSGID_RECEIVE: { PDPNMSG_RECEIVE preceivemsg; PacketGeneric *PGen; In LoginDirectPlayMessageHandler preceivemsg = (PDPNMSG_RECEIVE)pMsgBuffer; PGen = (PacketGeneric*)pReceiveMsg->pReceiveData; // Ignore the packet if we sent it originally if( preceivemsg->dpnidsender == g_dpnidlocalplayer ) break; // If it is a chat packet, send it out to all of the players if( PGen->dwType == PACKET_TYPE_CHAT ) { Defined by us in DPChatServer.h as a subclass of PacketGeneric. It has array of char (storing actual chat message) as an extra field 15

16 >preceivedata; void *packet; PacketChat *ChatMsg; // Convert the packet to a void stream ChatMsg = (PacketChat*)pReceiveMsg- packet = (VOID*)ChatMsg; // Send the chat packet to all clients hrsendservermessage(dpnid_all_players_group,p ACKET_TYPE_CHAT,packet); // Output it on our screen vshowtext(hlb_output,chatmsg- >sztext); break; hrsendservermessage() HRESULT hrsendservermessage( int player, //slot number that you want to send the message //to. Use DPNID_ALL_PLAYERS_GROUP to //send message to all clients DWORD dwmessagetype, //message type, defined in //DPChatServer.h PVOID pmsgbuffer //void pointer to the contents of the //message. Void pointer allows any type //of data for this parameter ); 16

17 HRESULT hrsendservermessage( int player, DWORD dwmessagetype, PVOID pmsgbuffer ) { DPNHANDLE hasync; DWORD dwlength; DPN_BUFFER_DESC bufferdesc; PacketGeneric *PGen; // Cast to a generic packet to get the size PGen = (PacketGeneric*)pMsgBuffer; dwlength = PGen->dwSize; if( dwlength == 0 ) return(0); Exit because we don t want to send empty message bufferdesc.dwbuffersize = dwlength; bufferdesc.pbufferdata = (BYTE*)pMsgBuffer; Set up buffer // Broadcast it if player set to zero if( player == DPNID_ALL_PLAYERS_GROUP ) g_pdpserver->sendto( DPNID_ALL_PLAYERS_GROUP, &bufferdesc, 1, 0, NULL, &hasync, DPNSEND_NOLOOPBACK ); else g_pdpserver->sendto( PlayerInfo[player].dpnidPlayer, &bufferdesc, 1, 0, NULL, &hasync, 0); return S_OK; SendTo() HRESULT SendTo( const DPNID dpnid, //client you want to send to const DPN_BUFFER_DESC *const pbufferdesc, //this is the actual message data const DWORD cbufferdesc, //how many msg buffers to //send with this call const DWORD dwtimeout, //time out, set to 0 if you want //to keep sending the lost message void *const pvasynccontext, //NULL DPNHANDLE *const phasynchandle, //can use it to cancel send //but if we set it to //DPNSEND_SYNC, this value //must be null const DWORD dwflags // SEE next page ); 17

18 SendTo -> flags (1) DPNSEND_GUARANTEED Guarantees message delivery DPNSEND_NOLOOPBACK Keeps the server from receiving its own messages DPNSEND_PRIORITY_LOW Queues the message with low priority DPNSEND_PRIORITY_HIGH Queues the message with high priority SendTo -> flags (2) DPNSEND_NOCOPY Keeps DirectPlay from making a copy of the DPN_BUFFER_DESC before sending the message. You cannot use DPNSEND_NOCOMPLETE with this DPNSEND_SYNC Process the send synchronously DPNSEND_NOCOMPLETE Keeps DPN_MSGID_SEND_COMPLETE message from being generated Cannot use DPNSEND_NOCOPY and DPNSEND_GUARANTEED flags with this one, and the async context must be set to null 18

19 SendTo -> flags (3) DPNSEND_NONSEQUENTIAL Lets messages arrive at the client s computer in any possible order -> only use this flag for non-critical packets DPNSEND_COMPLETEONPROCESS Causes DirectPlay to send a DPN_MSGID_SEND_COMPLETE message upon completion of a message being received by the client. You have to set the DPNSEND_GUARANTEED flag in conjunction with this flag IDirectPlay8 Client interface Initialize and do things as before 19

20 HRESULT hrinitializedirectplay( HWND hwindow ) { HRESULT hreturn; // Initialize COM hreturn = CoInitialize( NULL ); if( FAILED(hReturn) ) { MessageBox( hwindow, "Error Initializing COM", "DirectPlay Error", MB_ICONERROR ); return hreturn; // Create IDirectPlay8Client Object if( FAILED( hreturn = CoCreateInstance( CLSID_DirectPlay8Client, NULL, CLSCTX_INPROC_SERVER, IID_IDirectPlay8Client, (LPVOID*) &g_pdp ) ) ) MessageBox( hwindow, "Can't Create DPlayClient", "DirectPlay Error", MB_ICONERROR ); // Init IDirectPlay8Client Message Handler if( FAILED( hreturn = g_pdp->initialize( NULL, DirectPlayMessageHandler, 0 ) ) ) { MessageBox( hwindow, "Failed to Message Handler", "DirectPlay Error", MB_ICONERROR ); return -1; // Create a device address hreturn = CoCreateInstance( CLSID_DirectPlay8Address, NULL,CLSCTX_INPROC_SERVER, IID_IDirectPlay8Address, (LPVOID*) &g_pdeviceaddress ); if( FAILED(hReturn) ) { MessageBox( hwindow, "Failed to Create Device", "CoCreateInstance()", MB_ICONERROR ); return -1; // Set our service provider to TCP/IP if( FAILED( hreturn = g_pdeviceaddress->setsp( &CLSID_DP8SP_TCPIP ) ) ) { MessageBox( hwindow, "Failed to SetSP() for Device Address", "Invalid Param", MB_ICONERROR ); return -1; 20

21 // Create a host address hreturn = CoCreateInstance( CLSID_DirectPlay8Address, NULL,CLSCTX_INPROC_SERVER, IID_IDirectPlay8Address, (LPVOID*) &g_phostaddress ); if( FAILED(hReturn) ) { MessageBox( hwindow, "Failed to Create Host Address()", "Invalid Param", MB_ICONERROR ); return -1; // Set the host address to TCP/IP if( FAILED( hreturn = g_phostaddress->setsp( &CLSID_DP8SP_TCPIP ) ) ) { MessageBox( hwindow, "Failed to SetSP() for Host Address", "Invalid Param", MB_ICONERROR ); return -1; // Create connection complete event for later use g_hconnectcompleteevent = CreateEvent( NULL, FALSE, FALSE, NULL ); vshowtext(hlb_output,"<<--tcp INITED-->>"); return S_OK; Joining the server session A user click the join button -> msg is sent hrjoingame() is called 21

22 LRESULT CALLBACK fnmessageprocessor ( HWND hwnd, UINT imsg, WPARAM wparam, LPARAM lparam ) { char szmessage[256]; char szcompmessage[256]; char szmyname[32]; HRESULT hreturn; void *packet; PacketChat ChatMsg; switch (imsg) { case WM_COMMAND: { // Check for child window messages switch(loword(wparam)) { // Check if the user clicked the button case IDC_hBU_Join: hrjoingame( hwnd ); break; See next page HRESULT hrjoingame( HWND hwnd ) { HRESULT hreturn = S_OK; WCHAR wszhostname[256]; WCHAR wszclientname[256]; char szclientname[256]; char szip[256]; char szport[256]; DWORD dwport; DWORD dwlength = 256; DPN_APPLICATION_DESC dpnappdesc; DPN_PLAYER_INFO dpplayerinfo; vshowtext(hlb_output,"attempting Connection..."); // Set the Client info GetWindowText(hEB_InputName,szClientName,36); // Get name from Window Edit Box DXUtil_ConvertGenericStringToWide( wszclientname, szclientname ); 22

23 ZeroMemory( &dpplayerinfo, sizeof(dpn_player_info) ); dpplayerinfo.dwsize = sizeof(dpn_player_info); dpplayerinfo.dwinfoflags = DPNINFO_NAME; dpplayerinfo.pwszname = wszclientname; Setup info for the player who joins // Make this a synchronous call if( FAILED( hreturn = g_pdp->setclientinfo( &dpplayerinfo, NULL, NULL, DPNSETCLIENTINFO_SYNC ) ) ) { vshowtext(hlb_output,"failed to set client info"); return -1; // Prepare the application description ZeroMemory( &dpnappdesc, sizeof( DPN_APPLICATION_DESC ) ); dpnappdesc.dwsize = sizeof( DPN_APPLICATION_DESC ); dpnappdesc.guidapplication = GUID_CHATSERVER; If your client application s GUID does not match the server s Then a connection cannot be made HRESULT setclientinfo( const DPN_PLAYER_INFO *const pdpnplayerinfo, //stores player name and other info about client ); PVOID const pvasynccontext, //NULL DPNHANDLE *const phasynchandle, // a handle that lets you cancel //this operation const DWORD dwflags //1 flag -> DPNSETCLIENTINFO_SYNC, //which tells the function to process //synchronously 23

24 // Get IP from edit box GetWindowText(hEB_InputServerIP,szIP,32); // Get Port from edit box GetWindowText(hEB_InputServerPort,szPort,6); // Convert the IP to a wide string DXUtil_ConvertGenericStringToWide( wszhostname, szip ); // Convert the port string to a DWORD dwport = atol(szport); Created in hrinitializedirectplay() // Add host name to address hreturn = g_phostaddress- >AddComponent(DPNA_KEY_HOSTNAME,wszHostName,(wcslen( wszhostname)+1)*sizeof(wchar),dpna_datatype_string); if( hreturn!= S_OK ) { MessageBox( hwnd, "Failed to AddComponent()", "hrjoingame()", MB_ICONERROR ); return -1; // Add port number to address hreturn = g_phostaddress- >AddComponent(DPNA_KEY_PORT,&dwPort,sizeof(DWORD),D PNA_DATATYPE_DWORD); if( hreturn!= S_OK ) { MessageBox( hwnd, "Failed to AddComponent()", "hrjoingame()", MB_ICONERROR ); return -1; // Connect to the session hreturn = g_pdp->connect( &dpnappdesc, g_phostaddress, g_pdeviceaddress, NULL, NULL, NULL, NULL, NULL, &g_hconnectasyncop, NULL); // flags 24

25 if( hreturn!= E_PENDING && FAILED(hReturn) ) { vshowtext(hlb_output,"failed to Connect"); return -1; SetTimer( hwnd, TIMERID_CONNECT_COMPLETE, 100, NULL ); return(hreturn); HRESULT Connect( const DPN_APPLICATION_DESC *const pdnappdesc, //the application description we set up earlier ) IDirectPlay8Address *const phostaddr, //host address interface IDirectPlay8Address *const pdeviceinfo, //device address for the client //connection that you defined in //hrinitializedirectplay() const DPN_SECURITY_DESC *const pdnsecurity, //for future, therefore //NULL const DPN_SECURITY_CREDENTIALS *const pdncredentials, //NULL const void *const pvuserconnectdata, //send additional connect information to //the server. If you specify this, the //server receives a //DPN_MSGID_INDICATE_CONNECT //message const DWORD dwuserconnectdatasize, //size of the 6 th parameter void *const pvasynccontext, //user created context to be passed when //DPN_MSGID_CONNECT_COMPLETE message is //processed DPHANDLE *const phasynchandle, //must be NULL if you set //DPNCONNECT_SYNC const DWORD dwflags // has DPCONNECT_OKTOQUERYFORADDRESSING //and DPCONNECT_SYNC to set 25

26 Set up the connection timer Let it goes off every 0.1 second i.e. the system sends a WM_TIMER message to the main message loop every 0.1 second This saves the program from having to do a loop-intensive waiting The part of the code that handles WM_TIMER is in fnmessageprocessor() Check if this is the timer that we created case WM_TIMER: if( wparam == TIMERID_CONNECT_COMPLETE ) { // Check if the message is telling us our connection is complete if( WAIT_OBJECT_0 == WaitForSingleObject( g_hconnectcompleteevent, 0 ) ) { if( FAILED( g_hrconnectcomplete ) ) { vshowtext(hlb_output,"<<----connection IN-COMPLETE---->>"); else { vshowtext(hlb_output,"<<----connection COMPLETE---->>"); KillTimer( hwnd, TIMERID_CONNECT_COMPLETE ); break; This is returned if the event passed in is complete (apart from this, the event can have flag for success or failure) 26

27 In DirectPlayMessageHandler(), DPN_MSGID_CONNECT_COMPLETE is received by clientr once the server has accepted the connection When you get this message, you should signal the g_hconnectcompleteevent with the SetEvent() Before you do that it is best to set the return state of the connection to find out whether the server accepted or rejected the connection case DPN_MSGID_CONNECT_COMPLETE: { PDPNMSG_CONNECT_COMPLETE pconnectcompletemsg; pconnectcompletemsg = (PDPNMSG_CONNECT_COMPLETE)pMsgBuffer; g_hrconnectcomplete = pconnectcompletemsg->hresultcode; SetEvent( g_hconnectcompleteevent ); break; 27

28 Sending messages to the server Look in fnmessageprocessor() switch(hiword(wparam)) { case EN_UPDATE: // Get the text from the edit box GetWindowText(hEB_InputField,szMessage,256); // Check if they pressed enter if( szmessage[strlen(szmessage)-1] == 10 ) { // Get rid of trailing garbage szmessage[strlen(szmessage)-2] = '\0'; GetWindowText(hEB_InputName,szMyName,32); sprintf(szcompmessage,"<%s> %s", szmyname, szmessage); // clear input field SetWindowText(hEB_InputField,""); // // Send a chat packet to the server // ChatMsg.dwSize = sizeof(packetchat); ChatMsg.dwType = PACKET_TYPE_CHAT; strcpy(chatmsg.sztext,szcompmessage); // Convert the packet to a void stream packet = (VOID*)&ChatMsg; // Send the chat packet hreturn = hrsendclientmessage(packet_type_chat,packet); break; 28

29 HRESULT hrsendclientmessage( DWORD dwmessagetype, PVOID pmsgbuffer ) { DPNHANDLE hasync; DWORD dwlength; DPN_BUFFER_DESC bufferdesc; PacketGeneric *PGen; // Cast to a generic packet to get the size PGen = (PacketGeneric*)pMsgBuffer; dwlength = PGen->dwSize; if( dwlength == 0 ) return(0); bufferdesc.dwbuffersize = dwlength; bufferdesc.pbufferdata = (BYTE*)pMsgBuffer; g_pdp->send( &bufferdesc, 1, 0, NULL, &hasync, 0 ); return S_OK; Use Send() instead of SendTo() -client can only send to server, so no need to tell Who it sends to IDirectPlay8Client::Send() HRESULT Send( const DPN_BUFFER_DESC *const pbufferdesc, //the DPN_BUFFER_DESC data structure that contains the //message to send ) const DWORD cbufferdesc, //number of buffers passed in //the first parameter (currently //you can only send 1) const DWORD dwtimeout, //milliseconds, if 0-> keep sending void *const pvasynccontext, //NULL DPNHANDLE *const phasynchandle, //if you use //DPSEND_SYNC, you //must set this to NULL const DWORD dwflags //same as the flags of SendTo() 29

30 Review Server Initialize COM Create IDirectPlay8Server interface Create a device address Set TCP/IP as the service provider Set the server information using IDirectPlay8Server::SetServerInfo() Initialize the application description Add the port number to the device address Call the IDirectPlay8Server::Host() Client Initialize COM Create IDirectPlay8Client interface Create a device address Set TCP/IP as the service provider Create a host address Set TCP/IP as the service provider Create a completion event Set the client information using IDirectPlay8Client::SetClientInfo() Initialize the application description Add the host port number and IP address to the host address Call the IDirectPlay8Client::Connect() Set the connection timer to go off every 0.1 second 30