Ill start off with the usual
"chances are you're not ready, at all, to take on a large MMORPG, or even just an RPG for that matter, or even an online game at all, for that matter" speal.
Now that thats over (and surely ignored), multiplayer games are no simple task (atleast ones more complex than moving cubes around a matrix). Youll first need to decide which method of online you'll be using, Peer-2-Peer or Host/Client. P2P is where every player acts as a host, sending and recieving information from every other player. It has its advantages, but isnt good for MMO's. Host/Client is where one player is the host, (this doesnt have to be a "player", so to speak, it could be a server setup to just recieve and send out the data to all of the other players). The host, as just said, recieves all of the info from every player in the world, including their positions, rotations, messages their sending back and forth, if they're moving, shooting, what they're wearing, their stats, their name, their password, and a whole lot of other junk. The host then takes this info and performs all of the calculations, checking for collisions between each player and the world, processing the messages, pretty much everything. Then, the host sends out all of the data of each player to each player, at which time each player recieves the data and handles appropriately (repositing all of the other players in the world based on the positions sent, back, displaying everyone's messages, etc.).
As far as a login/logout system that remembers information, this isnt that hard. Assuming you're using a host/client method, the server (the host) would have all of the data for each player saved to it's harddrive. Then whenever a player logs in, it checks the player's name and password for an existing player file, if one is found it loads up the player. If a player creates a new character, it creates a new player file, saving all of the needed info.
Lastly, I hope you realize that runescape isnt an executable embedded in a webpage, its programmed in Java, a web-acceptable language. Embedding exe's in webpages might seem logical, and yes there are legit companies out there like igLoader that help to do it, but the ability for hackers to get into the executable and change it so that essentially everyone n the world is running a program made by the hacker, is extremely unsafe, and still a reality at this point.
Im sure this will blow over your head as it does most newcommers, and Im sure you're extremely dedicated to prove everyone wrong and make the world's next WoW/Runescape, or some other MMO program, but either way, I have to say it;
Dont do such a difficult project yet. MMO games are created by teams of hundreds of programmers, designers, graphic artists, and professional game developers. Most MMO's take years to produce, and require a constant dedication to the project, that means programming until the boss says stop, which is usually quite a long time.
Read the tutorials and make a bunch of smaller games, build up your experience, and then take on such a daunting task.
- RUC'
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