Hello! This question is khm.. maybe really stupid.

My friend asked, why can't I make a multiplayer for a game, which doesn't have? I said I don't know if it is possible, maybe I will remake a similiar game in another engine or something.

I said I will try. But how people make it? I mean, look at Euro Truck Simulator 2. It hadn't multiplayer, but someone made one.

GTA:SA hadn't either, but someone made. If I would like to make a multiplayer to an exsiting game, like GTA (i know it has, it's just an example), what do I need for it/how it is possible(if it is)?

Thanks in advance,

Dominik.

You need several years of experience programming in C, C++, and assembly language.

You also need lots of experience with:

- Reverse engineering
- Game programming
- Network programming
- A tremendous amount of patience and motivation


It's not easy, or fun, but it's possible.

It's not easy, or fun, but it's possible

It's not easy, true. Some people think it's fun, though! In fact, that's almost the only reason someone would spend every night for months (or years) to do it, because there's no money in doing so...

In my experience, you don't just need "a few" years of reverse engineering and systems programming experience; I'd say that you need ten years of programming experience (most of it with C, C++, and/or assembly) as well as knowledge how to use more low-level debuggers like WinDBG and such.

Which game?

Some games are very open to modding and you could probably do something like this as a mod using official apis, which would be much more stable and easier to support than hacking the memory of the running game and injecting your own code into it...

Thanks for replys! ;)

Programming is fun to me, and I always like to try something new, and learn something new! I know some about reverse engineering too!

Which game?

Now I can't say a concrete, but we have some games, that would be fun to play together, especially shooting games.

I'm still thinking about the working of the server part. :)

And sorry for bad english.

If the client is not packed (themida etc) the job is not that hard, but it takes more like a lot of time to figure out where to hook and how to draw more than 1 player (if this is not intended in the release version).

Basically you have to hook update functions for the current user and send new coordinates/actions to the server. This is the easy part, the harder part will be how to handle these actions on another client. You have to hook somewhere in the update functions and draw more than 1 user/actions blablabla. There is of course more than one way to do it.

If you really like a game, this is actually really fun to do