Synchronization in multiplayer

[pspeed]

@nnpa

But i use my server. I spent a lot of time writing my server. It’s easier to transfer your own than. Put a new one.

Except when yours is already missing 90% of what it needs.

@nnpa

. Don’t use json - but what use for send arrays and variables - It should work faster. -

I already answered this. Binary.
Binary.
Binary.
Binary.
Binary.
Binary.
Binary.
Binary.

4 bytes of integer is always better than 9 characters of string… multiply times number of components * number of objects… it makes a huge difference.

Sim-ethereal already does this for standard things like position and provides the tools to do it efficiently for other things. That’s why I can fit a whole object position update in something like 22 bytes.

@nnpa

. It is better to synchronize with one large packet (Which contains all users). +

Which sim-ethereal already does. Plus you have tools for client-side interpolation.

@nnpa

To reduce the number of packets from the client to the server - send the data only if the model has changed. +

Sim-ethereal already does this, too.

@nnpa

Synchronization of the physical position must be done when the object does not move and when the packet has been changed+

The “physical position” lives on the server. The client is only a view and it’s indexing into the interpolation of known good data.

@nnpa

There was not an resolved question how to transfer data faster than json?

Only because you didn’t read it.

@nnpa

Is it worth it to spend time on compression and encryption?

Probably not… unless you want to slow things down further.

@nnpa

PS: I think this topic will be useful to those who solve the same issues.

Most people who want to solve the same issues will use (at least as a starting place) the tools already provided.

[nnpa]

@pspeed

Plus you have tools for client-side interpolation.

nnpa:

Give me the link. thank’s

4 bytes of integer is always better than 9 characters of string… multiply times number of components * number of objects… it makes a huge difference.
9 characters of string = 18 bytes of UTF-8.

Algorithm? my code:

buffer = message.json.toJSONString().getBytes("utf-8");

@pspeed

Most people who want to solve the same issues will use (at least as a starting place) the tools already provided.

When I decided to make a game, I first wrote the server and then I selected 3d engine.

By the way, many people think that both the client server and 3d work better on C ++

[nnpa]

@pspeed

Binary.
Binary.
Binary.
Binary.
Binary.
Binary.
Binary.

1. translate all variables into bytes along with the type
2. Add a separator
3. Forwarding to the server
4. Restore from bytes to java variables
   ?

[pspeed]

@nnpa

By the way, many people think that both the client server and 3d work better on C ++

Many people think the earth is flat. What’s your point?

[pspeed]

@nnpa

Algorithm? my code:

buffer = message.json.toJSONString().getBytes(“utf-8”);

Ok, I’ll play along… but this is getting ridiculous so this will be my last reply.

{
myPosition = {
x = “123.56”
y = “456.78”
z = “901.23”
}
}

Is always always always going to take WAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAY more space than three floats stored as binary: 3 * 4 bytes.

Moreover, you can often pack those even smaller like Sim-etheral does and fit it all 5 or 6 bytes.

JSON/XML/etc. are nice when you must embed the structure in your data because you will be interoperating with 100 different types of clients and servers. But it’s SLOOOOOW. Dog slow. Butt slow. Snails are running circles around it.

If you control both ends of the channel then there is no reason to waste space and time with the structure. Both ends already know the structure.

Your entire server architecture is based on enterprise-style development practices that just don’t work for real time gaming.

You should read about GAME network synchronization and specifically “entity component systems” as a game architecture. If you want to scale up more than 1000 players at a time you are very much going to need something like an entity system.

That’s it. I’m out. It’s up to you to fail or succeed now. You’ve already got failure in the bag… so hopefully you can come to your senses soon.

[nnpa]

My meaning in this topic is how to optimize the: client, server, data transfer, memory, variables, etc. fast light

Interestingly about interpolation

The meaning of making the game good at least technically.

about java and c++
https://www3.ntu.edu.sg/home/ehchua/programming/java/JavaNativeInterface.html
ps: (Many games assemblies work better (it depends only on the hands and head of the developer I think)

[nnpa]

@pspeed

If you control both ends of the channel then there is no reason to waste space and time with the structure. Both ends already know the structure.

but now not 1994 year. You propose a procedural approach?

My friends write a connection to the database in assembler.
(facebook and vk Broadcast to low-level C)

We came to the conclusion that it is not necessary to optimize until the problem has appeared.

Better:

1. provide scaling
2. Buy the best internet
3. buy a better server

than:

1. Debug the low-level code.
2. Spending human time.

http://www.kriconf.ru/

Конференция разработчиков высоконагруженных систем HighLoad++

Профессиональная конференция веб-разработчиков Devconf 2019

PS: General findings of the developer community.

[nnpa]

You want to say:

1. You make structure (or class).
2. Translate to bytes.
3. Send and receive
4. make class (or structure) from bytes
5. execute

?

This:

package com.example;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

public class Serializer {

    public static byte[] serialize(Object obj) throws IOException {
        try(ByteArrayOutputStream b = new ByteArrayOutputStream()){
            try(ObjectOutputStream o = new ObjectOutputStream(b)){
                o.writeObject(obj);
            }
            return b.toByteArray();
        }
    }

    public static Object deserialize(byte[] bytes) throws IOException, ClassNotFoundException {
        try(ByteArrayInputStream b = new ByteArrayInputStream(bytes)){
            try(ObjectInputStream o = new ObjectInputStream(b)){
                return o.readObject();
            }
        }
    }

}

[Domenic]

@pspeed, why pointing to your libraries when he doesn’t give a shit on them anyway? In my opinion, he rather should learn the basics of the JME networking api first before going on with those advanced libs.

However, I have the feeling that he is not really talking us seriously anyway…

[nnpa]

Big idea:

I form the message on 3 packages - an example:
send_to_server : {
update player_id: 22 camDir -0.19635175 -0.02604162 -0.22531715,
update player_id: 22 camLeft -0.15078059 1.14738945E-7 0.13139714,
update player_id: 22 camDir -0.19635175 -0.02604162 -0.22531715,
}

This will reduce the number of tasks and messages 3 times

From server packet:
player_1:
{
update player_id: 22 camDir -0.19635175 -0.02604162 -0.22531715,
update player_id: 22 camLeft -0.15078059 1.14738945E-7 0.13139714,
update player_id: 22 camDir -0.19635175 -0.02604162 -0.22531715
}
player_2:
{
update player_id: 22 camDir -0.19635175 -0.02604162 -0.22531715,
update player_id: 22 camLeft -0.15078059 1.14738945E-7 0.13139714,
update player_id: 22 camDir -0.19635175 -0.02604162 -0.22531715
}
…
player_6:…

One big packet with 3 lats player packets:

On client:

1. Set the coordinates in turn.

_____________________________________________-

1. Reduce the number of messages to order 3 times
2. Reducing the number of messages from the server 18 times.
3. Failures in network operation will not affect the display of 3d

[Mark_Pyrizhok]

Did you read last Paul’s post? he provide you a tool to solve your issue. do you really want to write your own?

and yes, this topic is useful. It provide a good understanding of synchronization in multiplayer, since experienced developers point to that so many times, that it is very hard to miss that.