The Grand Multiplayer Thread

Well, you asked and you get.

I'll start with the basics and explain a bit.

There are two main ways of creating a multiplayer Flash game. All the ways require knowledge of another programming/scripting language (I'm not including the MM server, too expensive) and are not for beginners. Making a multiplayer game requires knowledge about a lot of different things, quite often you will need to know SQL (Structured Query Language) to store stuff in databases as well as your other language. Anyway, the two main ways to implement a multiplayer flash game are

Polling
This is the slower method, and not ideal for multiplayer games. This way, you create some server side scripts (in languages such as PHP, ASP, Perl, other CGI languages). Because of this, it is cheaper as most paid hosts allow some for of scripting.

This script must accept input in the form of variables in the query-string, like myscript.php?name=edmack&score=5 or via http POST (if you've made a form before you will understand this). The script must output plain text in the same form for flash to create variables from it. An example would be: score1=edmack&score2=Fred&score3=kim

Your flash script should do something along the lines of this to send your details, and add the variables it gets in response:

loadVariables("myscript.php?name="+myname+"&score= "+myscore+", this, GET);

This sends the variables
name = myname (var from flash)
score = myscore (var from flash)

Sockets
This is the fastest and best method. It requires that you have some sort of server sitting listening on some computer. This is usually a program of some kind, and typically requires more programming knowledge than the polling method. This can be acheived with Java, PHP (requires uncommon special settings), C, C++, Visual Basic, Python, Perl, and just about any other programming language.

The reason sockets are far superior to the polling method is that it is almost like a piece of tube is held on end by both sides, the client (Flash) and the server (whatever). At any time you can send text down this tube, and the server will know it's from you, and be able to quickly send stuff back. This is unlike the polling method, where you have to connect and disconnect to the HTTP server every time. An added advantage of the socket option is that the server will know when you disconnect, but with the HTTP option it will just have to pronounce you dead after X amount of seconds have passed.

I've included a simple example of a socket based game (it uses the free CommServer from a brilliant site www.moock.org . They offer an excelent server called Unity which is like the shell of a house, you just create the rooms... check it out if you know java).

http://www.koyote.dk/flash_files/move_ball_multi.zip

Feel free to post links, info or questions. I'll try to check in every now and again.

Hey Ed,

Whats Happening? I havent been on for a long time (i think)! Ummm.....i was wondering, do you know about Unity? I tried using the example you posted with the unity server, but it just doesnt seem to work :( Do you know how to make objects and have them show up on the other peoples computer while they are moving? Also, do you know howto create Channels? Sorry if i asked WAY TOO MUCH!

Thanks!

Great sticky Ed Mack.

Personally I have had great success with the Polling solution.

This solution is great for turn-based games, board games, or games that do not require a continuous connection the server. I would reccommend connecting to the server every 5+ seconds. I have found that less then 5 seconds may stun your server. :confused:

More Information:
http://www.ultrashock.com/tutorials/...multiuser.html - Ultrashock Multi-user Tutorial

Example:
http://www.rocketsnail.com/chat/penguin/ - Penguin Chat

Once again "this is not for beginners". I would like to encourage you to partner with a programmer that understands server side scripting.

I hope this was helpful.

rsnail

I am very good at VB and have currently used ASP with my flash mutli player games. I made an multi-user chatting system when each use can walk around and chat, but i found even tho it was running as fast as possible, it was just too slow.

I would like to create a game using sockets. I have recently been learning visual basic creating applications in MS visual studio. Are there any tutorials showing me how to connect to a server etc?

It is possible to insert a flash object in a VB app and communicate in realtime between the two when the app is running.

Sure can =)

In vb, start a new project. Then, go under the project menu and select components. In there place a checkmark next to the Shockwave Flash object. This will add another icon to your box on the left hand side. You can now insert a flash movie by creating it like any other control.

There are 2 ways to script between vb and flash. 1) vb simply pulling or doing things to the flash movie, 2) is flash telling vb to do something.

Example of 1
http://www.macromedia.com/support/fl...hflash_03.html
All of these scripting methods can be used. VB can tell a movie to goto a frame, do a loadmovie, and even change a variables value.

Example of 2
Flash has a wonderful thing called an fscommand. VB will run an event when it recieves one of these commands. So flash could do:
FScommand("showSave")
and when vb gets the fscommand showSave it could popup a commonDialog control to save whatever.

These methods could be used to give flash multiplayer capabilities using vb's winsock control. Or to do multiplayer you could have a flash movie connect to a vb server using sockets =D

brain is exausted... must stop typing... need more info with vb/flash im your man ;)

Nugget

Ello Ed

great thread, this topic to a degree always seemed to be shrowded in mystery. Maybe you could help me with my problem? I've downloaded CommServer from Moock.org, and uploaded the relevent files to a directory in my domain. Now I'm having trouble getting the thing up and running. According to the readme.txt supplied with the files I need to have either JDK or JRE 1.0+ installed on the server and the ability to run java programs (I have emailed my hosts to ask if the server meets these requirements and they're yet to get back to me).

My problem though is getting CommServer to run. The readme file says I need to navigate to the directory containing the CommServer files and start CommServer by typing:

"java CommServer [port]"

where [port] is the port CommServer will use. When I tried to do this I go this error message:

500 JAVA not understood.

does this mean my host doesn't have java on thier server?
My hosts run Unix servers, would the command be the same as a Window server?
If I can't use a Java based socket server, is there one based on a different language that might be more successful?

Sorry to drone on a bit, but I really want to get this working!

Thanks
m_andrews808

Here are two open-source multiplayer Flash games (pool and a puzzle game) and two open-source chats:
http://www.electrotank.com/ElectroServer/
Look for the 'examples' section.

Here is one more open-source multiplayer Flash game. This one is real-time:
http://www.gamebook.net
Scroll to the bottom and look for the maze link.

All of these examples use ElectroServer which is a socket-server found at the first link.

Quote:

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Originally posted by xMCNUGGETx2
Sure can =)

In vb, start a new project. Then, go under the project menu and select components. In there place a checkmark next to the Shockwave Flash object. This will add another icon to your box on the left hand side. You can now insert a flash movie by creating it like any other control.

There are 2 ways to script between vb and flash. 1) vb simply pulling or doing things to the flash movie, 2) is flash telling vb to do something.

Example of 1
http://www.macromedia.com/support/fl...hflash_03.html
All of these scripting methods can be used. VB can tell a movie to goto a frame, do a loadmovie, and even change a variables value.

Example of 2
Flash has a wonderful thing called an fscommand. VB will run an event when it recieves one of these commands. So flash could do:
FScommand("showSave")
and when vb gets the fscommand showSave it could popup a commonDialog control to save whatever.

These methods could be used to give flash multiplayer capabilities using vb's winsock control. Or to do multiplayer you could have a flash movie connect to a vb server using sockets =D

brain is exausted... must stop typing... need more info with vb/flash im your man ;)

Nugget

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I've gotton that far and mastered using FS commands but i need info on sockets etc.

Here is a link to short but informative thread that I started sevreal weeks ago. It contains some general socket-server information that would be informative to developers who have never used them before.

http://www.flashkit.com/board/showth...hreadid=412184

Thanks for another cool sticky :p

I was just wondering on how to make a server on my pc... So that the multiplayer games goes through the pc and not through a free webhost...

If I'm right... this is possible :)

mosterdfles_flash,

Here are the basics of doing just that:
As you probably know, all Flash needs to know in order to connect to a socket-server is the ip of the server and the port. Well, when you use a socket-server that will install on your own PC, like ElectroServer, then you just start it up on some port. When you connect to the Internet find out your IP address. You can then give this IP address and port to anyone else that you know and they can connect to the version of ElectroServer (or another socket-server) running on your PC.

The downsides:
1.) If you are behind a router (like for cable or DSL Internet, or at an office) then the router has the IP. When a connection request comes in from the Internet, the router doesn't know which computer to forward it to. So you have do some port forwarding (I think that's what it is called) on your router. Your router should have an admin tool to let you do that. Each sub-computer connected to your router has an internal network IP. You should forward the port that the socket-server is using to your computer IP. Then things should work for you!

2.) You have setup a socket-server, not a file server. As you probably know, Flash can only connect to a server on its own domain. So you can't put a SWF in a web page on www.imakeflashgames.com and have it connect to your personal server. In order for a SWF file to connect to your socket-server either: a.) it must come from your own machine, or b.) It must come from the hard drive from another person. The cross-domain security restriction doesn't work when working directly off of the hard drive. So you can have people download your game to their comptuers and then it would work. There is a "c." option too, c.) Actually run a file server on your computer too. That way you can also serve up the SWF file and then it *can* be used in a web page. But I don't have any suggestions on how to accomplish that.

In the Electrotank early days, about 2 years ago, I hosted ElectroServer on a computer from my apartment. A friend help me set up apache server on it so that it could also serve up some SWF files. It worked like a charm for several months before we bought a real server at an ISP.

Quote:

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Originally posted by m_andrews808
My problem though is getting CommServer to run. The readme file says I need to navigate to the directory containing the CommServer files and start CommServer by typing:

"java CommServer [port]"

where [port] is the port CommServer will use. When I tried to do this I go this error message:

500 JAVA not understood.

---

Are you by any chance typing that command into an ftp connection?

You need to connect via a terminal program.

Also, *nixs are CaSE SenSitive. "java" != "Java" ect... Type your commands in lowercase (though, you need to use the correct name of the class file, "CommServer"). So type:

java CommServer 9999 [hit return]

And it should work.

Thanks for the reply, but unfortunatly my host doesn't have JDK or JRE so its no go. Only way I can do it is to turn my own computer into a server and install the necessary on there

Quote:

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Originally posted by rpgprogrammer
Hey Ed,

Whats Happening? I havent been on for a long time (i think)! Ummm.....i was wondering, do you know about Unity? I tried using the example you posted with the unity server, but it just doesnt seem to work :( Do you know how to make objects and have them show up on the other peoples computer while they are moving? Also, do you know howto create Channels? Sorry if i asked WAY TOO MUCH!

Thanks!

---

The example I posted will only work with CommServer.

Unity has what you call "channels", only they are called rooms in unity.

Look into the RoomInstances.xml file to see the layout of the rooms. The <defaultroom> portion is the room the client is put into upon connection. This is normally "DispatcherRoom", which allows the user to select a room they want to goto via sending a string like this:

<message type="requestRoom"><ROOMID>myroom</ROOMID></message>

Creating objects and displaying them is something that can be done many ways. Check my example fla for how I did it. It requires a good bit of logic programming. Basically, when someone enters, they broadcast their name to everyone, along with coordinates ect.. and all the other clients add that person, then broadcast their details (there must be checking in the clients that they don't add the same person twice, I acheived this with an object holding all the clients).

Then, when they want to move, the client broadcasts its distination, and all the clients move their movieclip of that player.

That only works with simple games. Wehn you have complicated levels, and pathfinding comes into play you get a headache of people moving, and one player will send their path, someone else does the same and then they collide. It's better to do pathfinding serverside, especially when using a fast language like java

Quote:

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Originally posted by m_andrews808
Thanks for the reply, but unfortunatly my host doesn't have JDK or JRE so its no go. Only way I can do it is to turn my own computer into a server and install the necessary on there

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Ask your host why they removed java, as it's normally installed on unix machines. The worst you could do would be to remove all your own files!

heh..... ...he....heh.... don't say that :eek: :D

If you own you own domain, then you prolly can do what im playing with. Its called a DNS pointer. It allows you to point a subdomain to a different ip then your normal webspace. Hey you could point it to your local machine even ;)

for example my game could be hosted at my webspace at xmcnuggetx.com, but i could have a dns pointer lets say (myserver.xmcnuggetx.com), and point it to my local machine.

Flash will allow a movie to connect to a subdomain, even if its a different ip =D *JOY*

Nugget

http://www.winsockvb.com/article.php?article_id=18

Tutorial for excepting multiple connections using the winsock control. Wasnt specifically desinged for flash to connect to but it works =)

Nugget

Thanks Ed!

Hey Everyone,

if you want a good server to start with, go with ElectroServer.