Multiplayer tutorial 4: real-time game

Favourite 74 favourites
Tutorial written by AshleyOriginally published on 19th, March 2014 - 4 revisions

The rest of the Signalling group is more similar to the chat example; however there are still some more differences to come. First of all as before, once connected we log in with our username.

Then once logged in, we join the game room. As with the chat example, everyone who joins will end up in the same game. There's no limit here, and no need for auto-join as in the Pong example.

Once joined, we establish if we are the host. We do the same as the chat example: either the Host or Peer group is activated. However we also need to handle the Peer object already in the layout depending on whether we became host. If we're a peer, it's easy: we just destroy the object already in the layout. Sync object will automatically create, move and destroy any objects that are present on the host, including the object that represents our own player. However when we are the host, we adopt the existing Peer object in the layout as our own object that we control.

As with the pong example, the Peer object has a peerid instance variable to store the signalling-assigned peer ID. The Associate object with peer action is again also necessary to indicate to the multiplayer engine that this instance represents a player in the room. In this case we're adopting the object already in the layout, so we associate it with our own ID.

The remaining events in the Signalling group cover error handling in the same way as before.

Share and Copy this Tutorial

You are free to copy, distribute, transmit and adapt this work with correct attribution. Click for more info.


Tedg 9,849 rep

Awesome tutorial and awesome tool :)

Wednesday, March 19, 2014 at 5:21:07 PM
Jayjay 19.0k rep

Thanks for this tutorial! :D

Wednesday, March 19, 2014 at 5:51:25 PM
superwifibattler 3,322 rep

How do you make this with a drag&drop game or a board game or something?

Wednesday, March 19, 2014 at 7:02:12 PM
exertia 2,625 rep

@ashley - is there a way to restrict # of players to say 2 or a predetermined number, and force additional players into a new room / game.

Wednesday, March 19, 2014 at 8:33:47 PM
SergioRM 6,879 rep

really interesting! thank you!

Wednesday, March 19, 2014 at 9:59:39 PM
rexrainbow 137.5k rep

Like @superwifibattler said, the prediction might not be useful in some cases like turned based game (board game, poker game) , could Ashley provide some hint about that?

Wednesday, March 19, 2014 at 11:15:51 PM
Joskin 6,089 rep

Thanks for this tutorial ! It's not easy !

@rexrainbow, what about using the messages system for cards game ?
I can try to make a simple example.

Thursday, March 20, 2014 at 9:06:27 AM
rexrainbow 137.5k rep


Yes, I know it's possible.
My idea is -
1. [peer] request a command
2. [peer] validate this command (could I run this command?)
3. [peer] if validated pass, execute this command and send this request to host

4. [host] receive command , then validate it
5. [host] if validated pass, execute this command and send this request to other peers
- if validated failed , something with that peer

6. [other peer] get validated command, execute it.

The validation function and execution function will be the same at host and peer. (peer and host will use the same function to validate command)

Thursday, March 20, 2014 at 9:34:26 AM
potpie1010 2,836 rep

Awesome tutorial; great feature.

There's no other game engine that's fun to use, yet is still able to produce actual games.

Multiplayer should be interesting!

Thursday, March 20, 2014 at 1:18:01 PM
bilgekaan 23.4k rep

Great feature and tutorial thank you!

Friday, March 21, 2014 at 11:48:30 PM
dynamiczny 438 rep

Is there any chance of obtaining the code for the signaling server? After all I would not like to infinitely rely on the server which I don't even have access to..

Could you provide the code so that we could set up our own signalling servers?

Tuesday, March 25, 2014 at 2:30:26 PM
qu0y 3,126 rep

Thank you Ashley!

Saturday, March 29, 2014 at 2:09:01 PM
drappdev 2,164 rep

I think i missed the section around the room size.
If i change the "Max Peers" value to 2, and then open 4 separate browser windows to the localhost:50000 address. the first 2 i login are entered into the room, whilst the 3rd & 4th are given the error "signalling error: room full".
If anyone knows how to push the extra players above the max peers into 'new' rooms. I would really appreciate the knowledge share.

Tuesday, April 01, 2014 at 10:08:55 PM
AbelaNET 14.7k rep

Ashley, thanks. Great info.

Wednesday, April 02, 2014 at 8:20:19 AM
Wsoukkachang 1,433 rep

@drappdev The new auto-join feature should help you with your problem.

Thursday, April 10, 2014 at 3:26:15 AM

Leave a comment

Everyone is welcome to leave their thoughts! Register a new account or login.