Juggernaut gem for game server

Question

It's about latest Juggernaut gem (https://github.com/maccman/juggernaut)

I'm thinking of architecture, for, let's say, 'Dots games'. This meta-game is very simple: each logged in user (subscribed to channel, in terms of Juggernaut) is a dot of random color on JS canvas. User can move his dot any direction. That's it.

Juggernaut should transport and push all data for clients connected.

Currently i immagine architecture as:

1) Client(s) pushes coordinates of dot and player's id ([1, [10,299]]) as ajax to, for example, Rails.

2) Rails pushes this data to Juggernaut

3) Juggernaut push coordinates back to all clients who listen to this channel.

Juggernaut.publish("coordinates_channel", [1, [10,299]])

Problems:

1) When i need to pixel-by-pixel movement for 'dot' object on js canvas, i'll need to send too many AJAX requests. For example, if my dot moves 20 pixels per second, i'll need to send 20 requests per second. Unacceptable.

2) Should i wrap Juggernaut.publish into asynchronous loop (using EventMachine for example)? Because, just immagine 1000 of clients (1000 of dots, and constant flow of data with updated coordinates)...

Or maybe i get wrong client-server using Juggernaut gem? What do you think of this implementation?

Thank you.

Answer 1

WebSockets/Long polling/other comet techniques have low latency, your game will lag. I have seen implementations of real time games via websockets, they either lag, either game mechanics are made specific, like making the players move really slow to account for low latency. Classic AJAX is definitively out of the question.

Here's some resources on improving lag
Valve Source Multiplayer Networking
Unreal Source Multiplayer Networking