by Brent Rossen Using .net 2003

This tutorial is based on the SimpleEventConnection tutorial at OpenTNL.org, much of the code is identical. A few corrections
and improvements have been made. No Ogre specific calls are made in this file to keep the code as general as possible.

Please, use this forum thread (http://www.ogre3d.org/phpBB2/viewtopic.php?p=156411) to discuss problems, suggestions, etc.

INSTALLATION & USAGE:

Download OpenTNL from: http://www.opentnl.org/download.php (TNL code snapshots), unzip tnl.zip into your Project folder
(should unzip into a folder called "tnl"). Open the tnl solution (tnl/tnl.sln) and compile in both debug and then release mode,
so you have both.

Visual Studio Sections for Linking and Setup

Linker - Input - Additional Dependencies: libtomcryptd.lib tnld.lib wsock32.lib (libtomcrypt.lib and tnl.lib for release mode)

Linker - Input - Ignore Specific Libraries: LIBCD.lib (LIBC.lib for release), this may not be necessary for all applications,
will give compiler error if it is

Linker - General - Additional Library Directories: tnl/lib

C++ - Language - Enable Runtime Type Info - Yes (/GR)

A Few Notes

1) Make sure the interface for SimpleEventConnection is identical on both the server and client
Both must have all methods implemented, but only the client needs to actually perform client
functions and only the server needs server functions, they just both need to call the implement
macro for all methods

2) Enter the correct cmdAddress and port in the startXConnection() method (127.0.0.1:28001 is for running locally,
any other unused port works too)

3) Call startServerConnection() or startClientConnection() to get things started, the server should be started first

4) Call checkMessages() regularly to keep messages going back and forth smoothly

5) All "TODO:" notes are marked as things you should do and depend on your implementation

6) Please note that the server must call the broadcast functions, or find the appropriate
SimpleEventConnection as is done in the broadcast functions to call the client rpc methods

Put this in server.bat file to run in console. Close console window when finished.

SimpleNetTest.exe -server


Put this in client.bat file to run in console. It will close when done running. Navigate to project folder in a console window (Run>"cmd") and type the same if you want the window to stay open.

SimpleNetTest.exe -client


You should receive "Hello Clients (Server)!" back and forth as well as SetAnimation, PlayAudio, and SetObjectPosition calls

A Brief Explanation of the Original Use:

I am a Graduate Researcher at the University of Florida. We are working on an Interpersonal Simulator using ogre and have
a separation between the "Brain" of the on screen avatar and the "Frontend" (OGRE, FMOD, etc). So, the cleanest
way to maintain this separation was to have them communicate through network protocol. That way, if we want to
run the brains and renderer on different machines, or possibly have multiple rendering systems, we have that option.
OpenTNL was my choice for this. This setup is not intended to scale into an MMO! You need to thoroughly review
the OpenTNL documentation for a project of that magnitude. I wish you luck with OGRE and OpenTNL!

SimpleNet.h

#include "../tnl/tnl.h" 
#include "../tnl/tnlEventConnection.h" 
#include "../tnl/tnlNetInterface.h" 
#include "../tnl/tnlRPC.h" 
#include <stdio.h>
#include <string>

using namespace TNL; // make sure we can simply use the TNL classes. 

bool gQuit = false; // a flag used when the client wants to quit. 

class SimpleEventConnection : public EventConnection
{
    typedef EventConnection Parent;
private:
    RefPtr<NetInterface> theNetInterface;
    int messageLimit; //built in limit so the client will quit after 14 messages

public:
    SimpleEventConnection();
    // Let the network system know this is a valid network connection.
    TNL_DECLARE_NETCONNECTION(SimpleEventConnection);

    // declare the client to server message
    TNL_DECLARE_RPC(rpcMessageClientToServer, (StringPtr messageString));

    // declare the server to client message
    TNL_DECLARE_RPC(rpcMessageServerToClient, (StringPtr theMessageString));

    // declare the backend to frontend methods
    TNL_DECLARE_RPC(rpcSetAnimation, (StringPtr animation));
    TNL_DECLARE_RPC(rpcPlayAudio, (StringPtr audioFileName));
    TNL_DECLARE_RPC(rpcSetObjectPosition, (StringPtr name, float x, float y, float z));//items or cameras
    
    void confirmMessageReceipt(const char * message);
    void checkMessages();
    void startClientConnection();
    void startServerConnection();
    
    //server calls
    void rpcBroadcastMessageClients(StringPtr message);
    void rpcBroadcastSetAnimation(StringPtr animation);
    void rpcBroadcastPlayAudio(StringPtr audioFileName);
    void rpcBroadcastSetObjectPosition(StringPtr name, float x, float y, float z);
};

SimpleEventConnection::SimpleEventConnection(){
    messageLimit = 18;
}

//SimpleEventConnection implementations

TNL_IMPLEMENT_NETCONNECTION(SimpleEventConnection, NetClassGroupGame, true);

/**
Client to server message
Note, a ServerToClient method can be called within this ClientToServer method.
The rpcMessageServerToClient will be executed in the server application, and will
automatically be routed to the client connection who called it.
To reiterate, the client who called rpcMessageClientToServer will have rpcMessageServerToClient
called on it, that method will execute on the client side.
This can be a bit confusing at first, but you will get used to it.
**/
TNL_IMPLEMENT_RPC(SimpleEventConnection, rpcMessageClientToServer, 
                  (StringPtr messageString), (messageString),
                  NetClassGroupGameMask, RPCGuaranteedOrdered, RPCDirClientToServer, 0)
{
    // display the message the client sent
    printf("Got message from client: ");
    printf(messageString);

}

/**
The server to client messages
confirmMessageReceipt is used so that you only need to turn it off in one place
All of these server to client rpc functions have a corresponding broadcast function
it is important that you understand why the broadcast is used. If you tried calling these
directly from the newConnection object you would get an error because you need to know
which client to send the message to!
**/
TNL_IMPLEMENT_RPC(SimpleEventConnection, rpcMessageServerToClient, 
                  (StringPtr messageString), (messageString),
                  NetClassGroupGameMask, RPCGuaranteedOrdered, RPCDirServerToClient, 0)
{
    //confirm receipt of server call
    std::string str = "Messsage To Client Received: ";
    str += messageString.getString();
    str += "\n";

    confirmMessageReceipt(str.c_str());

    messageLimit--;
    if(messageLimit <= 0){
        rpcMessageClientToServer("Disconnecting. Good bye!\n");
        gQuit = true;
    }
}

TNL_IMPLEMENT_RPC(SimpleEventConnection, rpcSetAnimation, 
                  (StringPtr animation), (animation),
                  NetClassGroupGameMask, RPCGuaranteedOrdered, RPCDirServerToClient, 0)
{
    //confirm receipt
    std::string str = "Animation Request Received: ";
    str += animation.getString();
    str += "\n";

    confirmMessageReceipt(str.c_str());

    //TODO: play animation
}

TNL_IMPLEMENT_RPC(SimpleEventConnection, rpcPlayAudio, 
                  (StringPtr audioFileName), (audioFileName),
                  NetClassGroupGameMask, RPCGuaranteedOrdered, RPCDirServerToClient, 0)
{
    //confirm receipt
    std::string str = "Audio Request Received: ";
    str += audioFileName.getString();
    str += "\n";

    confirmMessageReceipt(str.c_str());

    //TODO: play audio
}

TNL_IMPLEMENT_RPC(SimpleEventConnection, rpcSetObjectPosition, 
                  (StringPtr objectName, float x, float y, float z), (objectName, x, y, z),
                  NetClassGroupGameMask, RPCGuaranteedOrdered, RPCDirServerToClient, 0)
{
    //confirm receipt
    std::string str = "Position Set Received For: ";
    str += objectName.getString();
    str += "\n";

    confirmMessageReceipt(str.c_str());
    
    //TODO: move objects
}

void SimpleEventConnection::confirmMessageReceipt(const char * message){
    // display the message the server sent
    printf(message);

    //TODO: comment this out when you no longer want message confirmations
    rpcMessageClientToServer(message);
}

void SimpleEventConnection::checkMessages(){
    theNetInterface->checkIncomingPackets();
    theNetInterface->processConnections();
}

void SimpleEventConnection::startClientConnection(){    

    Address cmdAddress("127.0.0.1:28001");

    Address bindAddress(IPProtocol, Address::Any, 0);

    // create a new NetInterface bound to any interface and any port
    theNetInterface = new NetInterface(bindAddress);

    // create a new SimpleEventConnection and tell it to connect to the
    // server at cmdAddress.
    connect(theNetInterface, cmdAddress);
    
    // post an RPC, to be executed when the connection is established
    rpcMessageClientToServer("Client Connection Requested");
}

void SimpleEventConnection::startServerConnection(){
    Address cmdAddress("127.0.0.1:28001");

    // create a server net interface, bound to the cmdAddress
    theNetInterface = new NetInterface(cmdAddress);

    // notify the NetInterface that it can allow connections
    theNetInterface->setAllowsConnections(true);
}

//broadcast functions send the message to all n registered clients
void SimpleEventConnection::rpcBroadcastMessageClients(StringPtr message){
    TNL::Vector<TNL::NetConnection* > con_list = theNetInterface->getConnectionList();
    for(int i = 0; i < con_list.size(); i++){
        SimpleEventConnection *con = (SimpleEventConnection *)con_list[i];
        con->rpcMessageServerToClient(message);
    }
}

void SimpleEventConnection::rpcBroadcastSetAnimation(StringPtr animation){
    TNL::Vector<TNL::NetConnection* > con_list = theNetInterface->getConnectionList();
    for(int i = 0; i < con_list.size(); i++){
        SimpleEventConnection *con = (SimpleEventConnection *)con_list[i];
        con->rpcSetAnimation(animation);
    }
}

void SimpleEventConnection::rpcBroadcastPlayAudio(StringPtr audioFileName){
    TNL::Vector<TNL::NetConnection* > con_list = theNetInterface->getConnectionList();
    for(int i = 0; i < con_list.size(); i++){
        SimpleEventConnection *con = (SimpleEventConnection *)con_list[i];
        con->rpcPlayAudio(audioFileName);
    }
}

void SimpleEventConnection::rpcBroadcastSetObjectPosition(StringPtr name, float x, float y, float z){
    TNL::Vector<TNL::NetConnection* > con_list = theNetInterface->getConnectionList();
    for(int i = 0; i < con_list.size(); i++){
        SimpleEventConnection *con = (SimpleEventConnection *)con_list[i];
        con->rpcSetObjectPosition(name, x, y, z);
    }
}

//runs either the server or client code depending on your call to argv
int main(int argc, const char **argv)
{
    if(argc != 3)
    {
        printf("usage: simpletnltest <-server|-client>");
        return 1;
    }
    bool isClient = !strcmp(argv[1], "-client");//check to see if we want to start a client or server

    SimpleEventConnection *newConnection = new SimpleEventConnection;
    if(isClient)
    {
        //This is your client protocol and should be run in your client application
        newConnection->startClientConnection();

        // post an RPC, to be executed when the connection is established
        newConnection->rpcMessageClientToServer("Client Connection Requested");
    }
    else
    {
        //This is your server protocol and should be run in your server application 
        newConnection->startServerConnection();
    }

    // now just loop, processing incoming packets and sending outgoing packets
    // until the global quit flag is set.
    while(!gQuit)
    {
        if(isClient){
            newConnection->rpcMessageClientToServer("Hello Server!\n");
        }
        else{
            newConnection->rpcBroadcastMessageClients("Hello Clients!");
            newConnection->rpcBroadcastPlayAudio("audio.ogg");
            newConnection->rpcBroadcastSetAnimation("Dance");
            newConnection->rpcBroadcastSetObjectPosition("ogreHead", 0, 200, -300);
        }
        //if you use SimpleEventConnection
        newConnection->checkMessages();
        Platform::sleep(10); //you may not need to sleep if you have a place to call check messages regularly, 
                                       //such as each frame
    }

    return 0;
}
<HR>
Creative Commons Copyright -- Some rights reserved.


THE WORK (AS DEFINED BELOW) IS PROVIDED UNDER THE TERMS OF THIS CREATIVE COMMONS PUBLIC LICENSE ("CCPL" OR "LICENSE"). THE WORK IS PROTECTED BY COPYRIGHT AND/OR OTHER APPLICABLE LAW. ANY USE OF THE WORK OTHER THAN AS AUTHORIZED UNDER THIS LICENSE OR COPYRIGHT LAW IS PROHIBITED.

BY EXERCISING ANY RIGHTS TO THE WORK PROVIDED HERE, YOU ACCEPT AND AGREE TO BE BOUND BY THE TERMS OF THIS LICENSE. THE LICENSOR GRANTS YOU THE RIGHTS CONTAINED HERE IN CONSIDERATION OF YOUR ACCEPTANCE OF SUCH TERMS AND CONDITIONS.

1. Definitions

  • "Collective Work" means a work, such as a periodical issue, anthology or encyclopedia, in which the Work in its entirety in unmodified form, along with a number of other contributions, constituting separate and independent works in themselves, are assembled into a collective whole. A work that constitutes a Collective Work will not be considered a Derivative Work (as defined below) for the purposes of this License.
  • "Derivative Work" means a work based upon the Work or upon the Work and other pre-existing works, such as a translation, musical arrangement, dramatization, fictionalization, motion picture version, sound recording, art reproduction, abridgment, condensation, or any other form in which the Work may be recast, transformed, or adapted, except that a work that constitutes a Collective Work will not be considered a Derivative Work for the purpose of this License. For the avoidance of doubt, where the Work is a musical composition or sound recording, the synchronization of the Work in timed-relation with a moving image ("synching") will be considered a Derivative Work for the purpose of this License.
  • "Licensor" means the individual or entity that offers the Work under the terms of this License.
  • "Original Author" means the individual or entity who created the Work.
  • "Work" means the copyrightable work of authorship offered under the terms of this License.
  • "You" means an individual or entity exercising rights under this License who has not previously violated the terms of this License with respect to the Work, or who has received express permission from the Licensor to exercise rights under this License despite a previous violation.
  • "License Elements" means the following high-level license attributes as selected by Licensor and indicated in the title of this License: Attribution, ShareAlike.

2. Fair Use Rights

Nothing in this license is intended to reduce, limit, or restrict any rights arising from fair use, first sale or other limitations on the exclusive rights of the copyright owner under copyright law or other applicable laws.

3. License Grant

Subject to the terms and conditions of this License, Licensor hereby grants You a worldwide, royalty-free, non-exclusive, perpetual (for the duration of the applicable copyright) license to exercise the rights in the Work as stated below:

  • to reproduce the Work, to incorporate the Work into one or more Collective Works, and to reproduce the Work as incorporated in the Collective Works;
  • to create and reproduce Derivative Works;
  • to distribute copies or phonorecords of, display publicly, perform publicly, and perform publicly by means of a digital audio transmission the Work including as incorporated in Collective Works;
  • to distribute copies or phonorecords of, display publicly, perform publicly, and perform publicly by means of a digital audio transmission Derivative Works.
  • For the avoidance of doubt, where the work is a musical composition:
    • Performance Royalties Under Blanket Licenses. Licensor waives the exclusive right to collect, whether individually or via a performance rights society (e.g. ASCAP, BMI, SESAC), royalties for the public performance or public digital performance (e.g. webcast) of the Work.
    • Mechanical Rights and Statutory Royalties. Licensor waives the exclusive right to collect, whether individually or via a music rights society or designated agent (e.g. Harry Fox Agency), royalties for any phonorecord You create from the Work ("cover version") and distribute, subject to the compulsory license created by 17 USC Section 115 of the US Copyright Act (or the equivalent in other jurisdictions).
    • Webcasting Rights and Statutory Royalties. For the avoidance of doubt, where the Work is a sound recording, Licensor waives the exclusive right to collect, whether individually or via a performance-rights society (e.g. SoundExchange), royalties for the public digital performance (e.g. webcast) of the Work, subject to the compulsory license created by 17 USC Section 114 of the US Copyright Act (or the equivalent in other jurisdictions).


The above rights may be exercised in all media and formats whether now known or hereafter devised. The above rights include the right to make such modifications as are technically necessary to exercise the rights in other media and formats. All rights not expressly granted by Licensor are hereby reserved.

4. Restrictions

The license granted in Section 3 above is expressly made subject to and limited by the following restrictions:

  • You may distribute, publicly display, publicly perform, or publicly digitally perform the Work only under the terms of this License, and You must include a copy of, or the Uniform Resource Identifier for, this License with every copy or phonorecord of the Work You distribute, publicly display, publicly perform, or publicly digitally perform. You may not offer or impose any terms on the Work that alter or restrict the terms of this License or the recipients' exercise of the rights granted hereunder. You may not sublicense the Work. You must keep intact all notices that refer to this License and to the disclaimer of warranties. You may not distribute, publicly display, publicly perform, or publicly digitally perform the Work with any technological measures that control access or use of the Work in a manner inconsistent with the terms of this License Agreement. The above applies to the Work as incorporated in a Collective Work, but this does not require the Collective Work apart from the Work itself to be made subject to the terms of this License. If You create a Collective Work, upon notice from any Licensor You must, to the extent practicable, remove from the Collective Work any credit as required by clause 4(c), as requested. If You create a Derivative Work, upon notice from any Licensor You must, to the extent practicable, remove from the Derivative Work any credit as required by clause 4(c), as requested.
  • You may distribute, publicly display, publicly perform, or publicly digitally perform a Derivative Work only under the terms of this License, a later version of this License with the same License Elements as this License, or a Creative Commons iCommons license that contains the same License Elements as this License (e.g. Attribution-ShareAlike 2.5 Japan). You must include a copy of, or the Uniform Resource Identifier for, this License or other license specified in the previous sentence with every copy or phonorecord of each Derivative Work You distribute, publicly display, publicly perform, or publicly digitally perform. You may not offer or impose any terms on the Derivative Works that alter or restrict the terms of this License or the recipients' exercise of the rights granted hereunder, and You must keep intact all notices that refer to this License and to the disclaimer of warranties. You may not distribute, publicly display, publicly perform, or publicly digitally perform the Derivative Work with any technological measures that control access or use of the Work in a manner inconsistent with the terms of this License Agreement. The above applies to the Derivative Work as incorporated in a Collective Work, but this does not require the Collective Work apart from the Derivative Work itself to be made subject to the terms of this License.
  • If you distribute, publicly display, publicly perform, or publicly digitally perform the Work or any Derivative Works or Collective Works, You must keep intact all copyright notices for the Work and provide, reasonable to the medium or means You are utilizing: (i) the name of the Original Author (or pseudonym, if applicable) if supplied, and/or (ii) if the Original Author and/or Licensor designate another party or parties (e.g. a sponsor institute, publishing entity, journal) for attribution in Licensor's copyright notice, terms of service or by other reasonable means, the name of such party or parties; the title of the Work if supplied; to the extent reasonably practicable, the Uniform Resource Identifier, if any, that Licensor specifies to be associated with the Work, unless such URI does not refer to the copyright notice or licensing information for the Work; and in the case of a Derivative Work, a credit identifying the use of the Work in the Derivative Work (e.g., "French translation of the Work by Original Author," or "Screenplay based on original Work by Original Author"). Such credit may be implemented in any reasonable manner; provided, however, that in the case of a Derivative Work or Collective Work, at a minimum such credit will appear where any other comparable authorship credit appears and in a manner at least as prominent as such other comparable authorship credit.

5. Representations, Warranties and Disclaimer

UNLESS OTHERWISE AGREED TO BY THE PARTIES IN WRITING, LICENSOR OFFERS THE WORK AS-IS AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE MATERIALS, EXPRESS, IMPLIED, STATUTORY OR OTHERWISE, INCLUDING, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTIBILITY, FITNESS FOR A PARTICULAR PURPOSE, NONINFRINGEMENT, OR THE ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OF ABSENCE OF ERRORS, WHETHER OR NOT DISCOVERABLE. SOME JURISDICTIONS DO NOT ALLOW THE EXCLUSION OF IMPLIED WARRANTIES, SO SUCH EXCLUSION MAY NOT APPLY TO YOU.

6. Limitation on Liability.

EXCEPT TO THE EXTENT REQUIRED BY APPLICABLE LAW, IN NO EVENT WILL LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY FOR ANY SPECIAL, INCIDENTAL, CONSEQUENTIAL, PUNITIVE OR EXEMPLARY DAMAGES ARISING OUT OF THIS LICENSE OR THE USE OF THE WORK, EVEN IF LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

7. Termination

  • This License and the rights granted hereunder will terminate automatically upon any breach by You of the terms of this License. Individuals or entities who have received Derivative Works or Collective Works from You under this License, however, will not have their licenses terminated provided such individuals or entities remain in full compliance with those licenses. Sections 1, 2, 5, 6, 7, and 8 will survive any termination of this License.
  • Subject to the above terms and conditions, the license granted here is perpetual (for the duration of the applicable copyright in the Work). Notwithstanding the above, Licensor reserves the right to release the Work under different license terms or to stop distributing the Work at any time; provided, however that any such election will not serve to withdraw this License (or any other license that has been, or is required to be, granted under the terms of this License), and this License will continue in full force and effect unless terminated as stated above.

8. Miscellaneous

  • Each time You distribute or publicly digitally perform the Work or a Collective Work, the Licensor offers to the recipient a license to the Work on the same terms and conditions as the license granted to You under this License.
  • Each time You distribute or publicly digitally perform a Derivative Work, Licensor offers to the recipient a license to the original Work on the same terms and conditions as the license granted to You under this License.
  • If any provision of this License is invalid or unenforceable under applicable law, it shall not affect the validity or enforceability of the remainder of the terms of this License, and without further action by the parties to this agreement, such provision shall be reformed to the minimum extent necessary to make such provision valid and enforceable.
  • No term or provision of this License shall be deemed waived and no breach consented to unless such waiver or consent shall be in writing and signed by the party to be charged with such waiver or consent.
  • This License constitutes the entire agreement between the parties with respect to the Work licensed here. There are no understandings, agreements or representations with respect to the Work not specified here. Licensor shall not be bound by any additional provisions that may appear in any communication from You. This License may not be modified without the mutual written agreement of the Licensor and You.