Minecraft Study Group

2021-09-08 Slides by Kenpou Nakajima in "Technologies supporting online games

Nishio agrees with this interpretation, adding that

Minecraft in the first place.

In a 3D virtual space

We can collaborate.

platform

Cannot be ignored when considering the virtualization of physical offices

Good features: low cost for users to improve the place

Just as kintone has enabled "any employee can create and improve business applications

Virtual offices on Minecraft can be created and improved by any employee.

Minecraft's ecosystem as of 2021

I'll explain this first.

vanilla

An official original release (common noun).

MOD (MOD server/MOD client)

Modified server and client

Mojang hired mod authors and developed an API to facilitate mod creation

Need to match mod versions on client and server

Two important elements arose after this

2012

A community of mod authors & users advocating free/open source

More than 300,000 members

Knowledge sharing is now taking place.

Now available in vanilla client

https://gyazo.com/5841196691409c19e1603c045517e672

Why is it now available to vanilla clients?

Resource Pack" feature added to vanilla

Additional model and texture changes can be made to create a new look and feel without modifying the client-side program

Accumulation of know-how to create additional function GUI with vanilla clients (see below)

Available in vanilla clients, i.e.

Without using different software (MOD clients) for each server,

Serviced by a single software (vanilla client)

This is the Web's

Without using different software for each server,

Services are available through a single software (Internet browser)

So the same situation was created as

Comparing to Web technology

Common Gateway Interface (CGI) is invented,

Run the program on the server side.

Dynamic behavior changes are now possible instead of static content delivery

This is what happened in Minecraft with the development of the plugin API

(To put a finer point on it, it runs in the same process as the server, rather than launching a separate process, so the situation is about the same as after mod_perl was born.)

Server-side implementation can be replaced as long as the API is followed.

Like turning Apache into Nginx.

This also occurs in Minecraft

Nowadays, PaperMC/Paper, which is touted as having improved performance over Spigot, is the mainstream.

So "Minecraft becomes a web of voxels."

Technically, it's already in that state.

Whether or not Minecraft becomes the de facto standard is the same as the browser market share battle.

Different layers of technology

What company owns Minecraft now?

It also seems that Microsoft wanted the ecosystem that Minecraft would create.

Minecraft is not just a game, but can also be considered a cloud-based digital entertainment platform. The future potential of Minecraft may have been highly evaluated because of its aspects that go beyond the realm of a simple game, such as being not only a game itself, but also killer content for live-action videos and modification content through mods (modification data, an abbreviation for modification).

Minecraft Extensibility

Create additional functionality GUI with vanilla client

https://gyazo.com/44401bcbf823b2d103ef59b4d54824e9

This is an in-game guide to a big-name industrialization plugin called Slimefun

It is actually a hack using the UI of a chest (a tool to store items)

The real chest is like this

https://gyazo.com/26d50a46a1f704e3ef3e96034b306ee7

Guide detail screen

https://gyazo.com/d4661d7820e35c8566e0219ca1911008

The UI of the chest and the hover text of the items explain what materials a nuclear power plant can be made from and what fuel it requires

Another example

https://gyazo.com/f899286d33e604335e721a48d0dde903

This is EconomyShopGUI, a plugin that introduces buying and selling of currency and items, which is also a chest

Plugin hooks into what is displayed in each slot and which slot is clicked

This is reminiscent of the "table layout" that used to be done on the web.

Hack to use the table tag for tabular layouts by removing all the rules and making it not look like a table, since HTML did not have the functionality to allow flexible layouts at that time.

Plug-in development

Spigot carefully explains how to make one from scratch.

Nishio never built from scratch, but modifying existing plug-ins was easy.

Clone source code from Github

Install Maven

Fix source code

build

Put it in the server plugin folder and restart the server

Slimefun's Programmable Android has been

https://gyazo.com/13bbb1e3f3ead884f0b242b49ace8b6c

It was just a matter of repeating and executing a specified sequence of instructions.

https://gyazo.com/421282cca9dbe33e2b6735d6bdb2c1b7

Enabled Python to run w

https://gyazo.com/3c2874d8a7d6c3b3609124bdf9744f58

protocol

Already analyzed.

The chest hack I mentioned earlier would

What kind of ID each slot in the chest has.

https://gyazo.com/b196dbe84fb8b2c7b6b9c9f2cdc17261

What packets fly when you click on a slot?

https://gyazo.com/522cdd83cae6491bf1264624f76543cc

is known

RCON

Protocol for executing administrative commands

Can throw packets from another process to execute in-game commands

Some commands are provided by vanilla, others are added by plug-ins

Examples of vanilla commands:.

Places a specific block on a rectangle at specified coordinates

/fill <x> <y> <z> <x> <y> <z> <block>

In the Java version, the destroy option performs itemization equivalent to mining with a pickaxe.

There is already a small program that throws RCON packets, so it is easy to control the server by throwing packets with cron.

Bot Development

PrismarineJS/mineflayer

Can write client side in Node.js

Example of Nishio's work

Bots to harvest grown crops and plant new ones

https://scrapbox.io/files/61517e27f11b61001db4a93b.mp4

code:js

function find_grown_nether_wart() {

return bot.findBlock({

point: bot.entity.position,

maxDistance: SEARCH_RADIUS,

matching: (block) => {

return (

block &&

block.type === mcData.blocksByName.nether_wart.id &&

block.metadata === 3

);

},

});

}

code:js

const toHarvest = find_grown_nether_wart();

if (toHarvest) {

const { x, y, z } = toHarvest.position;

const goal = new GoalNearXZ(x, z, 1);

if (!goal.isEnd(bot.entity.position)) {

await bot.pathfinder.goto(goal);

}

log("harvest");

await bot.dig(toHarvest);

log("done");

}

Building Export

Server file format is also known so it can be read or generated programmatically

Even vanilla actually implements reading and writing to files.

Using "Structural Blocks"

https://gyazo.com/59dbb384903d640ec60abdf31a1992eb

What Nishio hasn't tried yet

It should be possible to copy a part of a world and paste it into another world

It seems that the Java version and the Bedrock version (the version that runs on Switch, etc.) can be connected to the same server.

However, the Switch version does not have the ability to connect by specifying an IP address.

BedrockConnect Solution

Server administrator sets up a DNS server

People who play on Switch will have to tweak their network settings to use that DNS server.

I was able to connect, but it was slow.

Virtualization of physical offices

A lot of people have moved to remote areas assuming they don't come to work in the after-corona.

Physical offices became less usable as a place for employee collaboration.

Many people think about creating a virtual place.

Related services are myriad, but a few examples will be discussed

Oculus Room

Well-built model

Voice presentation utilizing device features

But customization is only a small option provided by the app

https://gyazo.com/c6c59b2bb9b4b76005d010212ea96163

VRChat

Both worlds and avatars are overwhelmingly customizable.

But if you try to create a world?

First, install Unity."

Many people drop out here.

Creating your own avatar is even more difficult than modeling, such as making sure the joints do not break down during animation.

Most people choose from what is available.

No sense of "being myself."

Minecraft

The world is composed of a combination of larger boxes.

Human-sized buildings are relatively easy to build by stacking blocks.

Anyone can make small tweaks, such as decorating with flowers.

Avatar is also a combination of square boxes

Paint is also coarse pixelated.

Easy to make by coloring in the browser.

https://gyazo.com/d8c85588b8c8f8c76242ecc596cfb9e9

It looks like a complex shape that doesn't look like just a square box painted with color.

In fact, there's one more layer to each body part, and it's used well for clothing and hair.

I made one too.

I don't have a particular idea of what I want to do, so I tried on clothes that I would normally wear. w

https://gyazo.com/d64736b2460b59fd7b4ee6359d497d09

This is basically without layers, only the pupils of the eyes are layered and placed in a non-pixel-like position.

Not being able to customize it doesn't give it a "feel of our own".

Outsourcing customization is expensive, and even if the financial cost is solved, it is a burden to translate requests into language.

This is the same approach as the popular "employees create their own business systems using kintone" approach.

Business systems that cannot be customized cannot be fixed even if dissatisfied.

If you don't like it and outsource the system, it's expensive, and modifications are also expensive, so in the end you can't fix it even if you are dissatisfied with it.

Shortfalls in the current Minecraft

No voice chat

We need voice chat with only those who have entered a certain distance or only those in the same room.

Technically, it should be possible to control the Discord audio channel from a plugin...

Let's have a party where all employees can get together on the micra!

This is a technical challenge, although it is easy to anticipate that the idea of

Limited to 20 simultaneous connections by default

It is easy to loosen the limit with options, but not easy to test how many people the server can withstand

Support for IT club activities

If you already have a clear idea of what you want to do, then support it.

People who do not have a clear idea of what they want to do.

While games are an incentive, we don't want them to just end up playing games.

That's where Micra comes in.

It is better to build an automated device than to have a human being repeat a simple task.

In fact, in an unexplored junior server full of players who can think programmatically...

https://gyazo.com/02a3a4236531d4ba9debf26461609371

https://gyazo.com/48ba56f96cfd31f0349c13027800f1d1

It's better for a human to learn commands than to repeat simple tasks.

Add plug-ins to add useful tools, commands, and new game features

To do that, you basically need to read the English documentation on Spigot and Github.

Plug-ins are open source

If you don't understand something from the documentation, you need to read the source code.

Or put an issue on Github

Or consult with us in English on our Discord channel.

If you're not happy with the plugin's functionality, you need to tweak the implementation.

and creates an incentive for a seamless modern programming experience from the game.

In China, they fight with tank robots that eject gel bullets.

Writing a program that compensates for manual control and creating an incentive to "learn programming to get stronger and win".

Learn to win" is the catchphrase.

https://gyazo.com/5170fa1ab74a3453ea083169c5c64836

To win, there will be an incentive to learn image recognition, etc.

But this approach would be difficult to adopt in Japan because of the strong allergic reaction to anything that reminds them of weapons.

Peaceful incentives are needed.

cost

Server costs are a bottleneck for Minecraft multiplayer.

Roughly this kind of cost with Conoha VPS

https://gyazo.com/4f1d68559de5d04a260a1bca4027316f

I'm not sure this time, so I'm trying the middle one for now for 3 months.

40,000 a year would be a heavy burden for elementary, middle, and high school students.

(I thought it would be convenient to have it installed as a template, but it was a vanilla server and I had to stop and re-install it on the first day of the program.)

If Cybozu were to provide this?

Looks good with lower SLAs than business system infrastructure.

How to avoid simply playing?

The same scheme as Cybozu's club support for employees could be used.

In other words, instead of providing funding, they ask for a report in a shared forum.

I want you to experience being on the side of disseminating technical information.

On the other hand, many teacher-parents have negative feelings about posting on the public Internet.

For example, how about using kintone as a closed social networking service?

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