iCloud Multiplayer! Guess The Number Game

• Game
• Multiplayer
• Text-Only
• Keyboard

SP4CEBAR 2025-10-07 14:40 (Edited)

We Have Online Multiplayer!

　　　　　　　　Open In Editor (single player)

How Is This Even Possible!?

An NX program can save and load data to a file named "Disk.nx". On IOS, your NX programs, including your Disk.nx, are stored on iCloud, but other platforms could do this as well. iCloud allows collaborating on a file online with others, so I shared Disk.nx files with all of you (see section Servers). When using a shared Disk.nx instead of your current Disk.nx, your program can "talk" to others that use the same disk.

This program is made to play a simple game as turn-based online multiplayer. I expect the program to be easily modify-able for other turn-based online games.

Gameplay

• Guess an integer number in range 1 to 20.
• The first player to guess correctly wins.

note: Choosing a player count of 1 allows playing single player so you can try it out below.

How To Set Up Multiplayer

• IOS Tutorial (iPad/iPhone)
• MacOs Tutorial (Mac/MacBook)
• Windows Tutorial (PC/Laptop)
• Linux Tutorial (PC/Laptop, less common)

Other Important Topics

• Disk.nx Servers
• Joining Orderly
• Plan Gaming Sessions

Game

• The first player gets to choose how many players will play multiplayer
  • The maximum is 12 as of now to allow each player to have it's own file on the disk as their "communications channel".
• The game should start once the specified number of players are connected, the program will keep you updated when players connect.
  • If more players join than set player count then these will become spectators.
• The program will end and the Disk will be reset when any player wins.
  • To play again, you should join again.

Technical details below

SP4CEBAR 2025-10-08 15:41 (Edited)

Technical details

• The first player, called "client 0" writes the game settings for the other clients to load.
• The program ends when the game ends, so you will have to connect before each game
• Each program will sample the Disk.nx file twice a second when waiting.
• there are 5 files in use, each of which using only a single byte:
  • the game settings (file 2)
  • the clients count (file 0)
  • the round number (file 1)
  • client 0's last response (file 3)
  • client 1's last response (file 4)

Multiplayer Example Code

Turn based

You may treat this code as an example of a turn-based multiplayer game, you could for example modify it into a card game.

Reveal

If you are more adventurous, you could mess with the code to make different multiplayer rules: game where each player can prepare their moves all at once before the result of them is revealed, like rock paper scissors.

All at once

You could even try to let each connected program modify their file (channel) continuously to sync the states of more action-packed games.

Improvement Ideas

1. Clients get the same ID if they join at the same time and become indistinguishable
   • have each client save a timer variable, to file 4 + TIMER MOD 12
     • this allows a two clients that joined near each other to be identified
     • there is still a 1 in 12 chance that both clients still wrote to the same file, in which case one of them may not be able to see the other's message.
     • I think the timer is counted since the app opened, PC clients that run an NX programs on boot may have the same timer value when they join

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Update 1: essential fixes

• added colors
• compacted game history
• disk is cleared after the game ends
• fixed your move not being displayed and evaluated (whether or not you guessed the number)

I tested it on Linux by running two NX instances and it actually works!

SP4CEBAR 2025-10-08 19:47 (Edited)

Update 2: reliability and clarity

• parameter configuration
  • support for more than two players
  • support for changing the lower and upper boundaries of possible numbers to be guessed
• various bug fixes
  • the player count and round number files are reset to 0 and $FF respectively for the next game
  • the file labels (variables that hold file numbers) can now be changed
• improved visuals now show what player is at play

jpospTynker 2025-10-09 00:02

this is SICK! it’s crazy multiplayer works in LOWRES NX now

SP4CEBAR 2025-10-09 11:51

I'm glad you like it!

SP4CEBAR 2025-10-09 13:49 (Edited)

Update 3: party player

• added an option for the host (client 0) to list the max amount of players
  • each client who joins will wait for this number to be revealed by the host before waiting for the remaining clients to join
  • the game does not work in single player: it hangs after first move

SP4CEBAR 2025-10-09 14:37 (Edited)

I shared a Disk with all of you!

Now you can play multiplayer on IOS! See program desciption above for more details.

Please let me know if you managed to open and modify the Disk, with an NX program on platforms other than IOS. I also just updated the description to provide more instructions and details.

SP4CEBAR 2025-10-09 16:24 (Edited)

Update 4: single player

• you can now choose to play single player by typing a player count of 1
  • The game can now be played in environments without a disk such as the web player above
• the input is sanitized so you can't play with -1 or 1.5 players
  • the upper limit of players is 12 as each player needs to have its own file as a "communications channel"

jpospTynker 2025-10-09 21:42

this is awesome, definitely doing something with this! imagine 12-player Co-op with fellow NXers!

SP4CEBAR 2025-10-10 13:06 (Edited)

I love the enthausiasm! I updated the instructions to make it clear for most platforms how to play.

All we need now is to arrange a time when anyone that wants to play will be online to play!
...as well as a joining order (with around 30 seconds between each joining player)

SP4CEBAR 2025-10-10 13:22 (Edited)

Also, if anyone wants to modify this turn-based online multiplayer example into a more complex game such as a card game, feel free to do so:

• the code is reasonably organized.
• you can test multiplayer programs on by opening an NX programs twice on PC so that two instances of the same program are running, you will not need any cloud service for this

SP4CEBAR 2025-10-10 18:45 (Edited)

Update 5

• Refactored the code to made it easier to modify/repurpose
  • the section "G A M E: G U E S S T H E N U M B E R" should contain all the code that defines the game behavior. It should be all you need if you just want to change the gameplay but keep the rounds
  • the section "T U R N - B A S E D M U L T I P L A Y E R" should contain all the code that defines the multiplayer rounds behavior. Modify this, if you want to make multiplayer games without rounds like rock-paper-scissors, or terraria (definitely the same level of complexity :) )

SP4CEBAR 2025-10-11 06:35

Update 6

• New palettes and screenshot

SP4CEBAR 2025-10-11 08:51

Here's an invitation to play multiplayer: Do You Want To Play The First Online Multiplayer Game?

Software Center 2025-10-11 14:38

Ummm I’m kinda confused could you simplify it. Btw I’m on iOS

SP4CEBAR 2025-10-11 20:00 (Edited)

Thanks for the feedback!
TL;DR An NX program can save data to a file named "Disk.nx". On IOS, your NX programs, including your Disk.nx, are stored on iCloud. iCloud allows collaborating on a file online with others, so I shared a Disk.nx with all of you (two actually, see section "Servers" above). When using this shared Disk.nx instead of your current Disk.nx, your program can "talk" to others that use the same disk. This program is made to play a simple game as turn-based online multiplayer. I expect the program to be easily modify-able for other turn-based online games.

jpospTynker 2025-10-11 20:20

woah now i wanna make a 4 player platformer

jpospTynker 2025-10-11 20:21

imagine r/place or something with this

SP4CEBAR 2025-10-12 06:16 (Edited)

Good luck, feel free to use code from here such as the connection phase. You can test multiplayer by opening an NX program twice on PC to launch two instances, you won't need any cloud for this. The possibilities are endless,

• but there will be latency, I don't know how much as I have not yet played over iCloud drive
• two devices writing at the same time may cause conflicts, iCloud may be able to resolve these automatically but that has to be seen.
  • I recommend giving each device their own file on the shared disk as their "communications channel" to make it easy to write without overwriting, hopefully this would also allow iCloud to resolve conflicts automatically
  • if iCloud can't resolve conflicts automatically, then each device might have to wait for its "turn" before it may save to the disk. This could happen automatically in the background.

SP4CEBAR 2025-10-12 14:46 (Edited)

Update 7

• Improved code structure so it makes sense to someone else reading it
  • especially the code that handles the turns, below is an example comparison
  • the turn_id of the first turn used to be -1 and there had to be an "empty turn" before the game started which made the code unnecessarily complicated, now we have a different variable that keeps track of the first turn,
    • while writing this report, I realized that we don't need to keep track of the first turn anymore, oh well.

code comparison

before

Even though it's short, it is hard to read what it does

MULTIPLAYER_TURNS:
  IF TARGET_CLIENT_COUNT > 1 THEN GOSUB RIVAL_TURN
  IF CLIENT_ID = TURN_ID OR TURN_ID = -1 THEN GOSUB YOUR_TURN
RETURN

after

This is much more straightforward

MULTIPLAYER_TURN:
  IS_YOUR_TURN= TURN_ID = CLIENT_ID
  IF IS_YOUR_TURN THEN
    GOSUB YOUR_TURN
  ELSE 
    GOSUB RIVAL_TURN
  END IF
RETURN

We also don't need the IS_YOUR_TURN variable anymore

jpospTynker 2025-10-12 15:07

i will try to make a platformer from this, with the acceleration the only thing online and the positions being stored in the game itself, but i still feel it will be nonstop conflict issues i have to fix :/

SP4CEBAR 2025-10-12 18:30

Good luck, have fun!

cmos 2025-10-14 02:30

too bad i don't have icloud D; (or anything apple for that matter)
i might try to get a google drive disk.nx up,
but no promises!

SP4CEBAR 2025-10-14 11:19 (Edited)

Good luck! note that the "Disk.nx" file has a capital "D", otherwise NX may not be able to find it.

You could also create a new apple account here, it does not require any apple device, but will give you 1GB instead of 5GB of iCloud drive. It also won't give you an "@icloud.com" email account