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  1. DrNegative15

    GMS 2 Issues with 'Movement and Collision with Multiple Moving Objects'

    Issue 1: Order of instance code execution affects movement behavior. Visual Aid for Issue 1: Scenario: 4 block instances are lined up one directly behind another and all are going to move together in the same direction. First they will all be moving to the right. (left side of...
  2. F

    Legacy GM (Gamemaker 8.1) How to make a multiplayer character select?

    How can I make a multiplayer character select in which one player host a game, others joins then everyone must select a character to start and they cannot select the same character
  3. solarcrispz

    GMS 2 Attempting to write outside buffer, line -1?

    Hey guys I've been putting together a multiplayer game with pretty good success. I've encountered "attempting to read from outside buffer, returning 0" errors before, but they're never as ambiguous as the one I'm consistently running into recently. Here it is: FATAL ERROR in action number 1 of...
  4. P

    Facebook Instant Chess Networking

    Hi to all. I have a big problem regarding networking and hope community can help. We made a chess game and we want to publish it as a Facebook Instant game. We have managed to do a little basic PC to PC, Android to Android, and Android to PC connection. The problem is HTML5 networking. We...
  5. C

    GMS 2.3+ Async atomocity?

    I am making a multiplayer game. Client #1 is constantly scanning for instances of object X. Client #2 asynchronously destroys one of those instances after it was already read on client 1. Then I get an undefined error when trying to reference it because that pointer obviously points to a...
  6. K

    GML Im making multiplayer game, but i dont know how to make that players would have moving sprites.

    I did all other things, but i only dont know how to make other players have sprite when they are moving? I can send project if you want. I did everythink like in this tutorial(there ), with some tweaks, but they dont matter:
  7. huenix

    Multiplayer Player Specific Objects/Layers with Networking Server Client issues....

    Hello..... i am making a multiplayer board game or sorts. What is done/working: -server/client buffers passed back/forth between each player (movement, sprites, etc) What I can't figure out and trying to do: -Player "A" and "B" are standing next to each other, both next to a room, with a...
  8. TheRudolfGaming

    SOLVED Client connecting to the server doesn't see already connected clients.

    Hello. I am currently in the foundation phase of a making a game with multiplayer functionality. But currently I've hit a speed bump and been unable to fix it for the last 3 days. I've made an non-dedicated multiplayer system, where one player hosts the game, and others connect. (Host will...
  9. A

    Second client crash in multiplayer

    I can't figure out why the second client on the server doesn't get the data in the buffer. Error: illegal undefined/null use I'm trying to query the coordinates and status of the player
  10. KyleRansford

    SOLVED Controller Input Using Object Variables Issue

    Can anyone tell me why this isn't working properly? I have made a Player Controller Input object o_input, o_inputP2, o_inputP3 & o_inputP4 with a menu Switch statement so each player can actually choose what slot their controller will be in. I have different modes the menus work in, but this...
  11. kroart

    Released Battle for Hexagon - simple abstract strategy [Android/iOS]

    Battle for Hexagon - it's an abstract logical turn-based strategy game. It has simple rules but still provides you a strategic challenge. You can play with an AI or online with other players. Key features: Simple rules Clear visual style Random map generator Multiplayer battles Different game...
  12. Bulldrome

    Local Multiplayer Help

    Hello I'm nearly finished with this little space ship arena game I've been working on and I just need to implement local multiplayer and I'll be just about done. I currently have 4 ships each with 4 colors set up on a character select screen of sorts but I need help setting up the controls for...
  13. D

    GMS 2 Losing connection after changing levels

    Like the title says, both players lose connection when I change rooms. Before hand, I'm new to networking and I'm spawning both of them on a setup room to verify if both players are working correctly. However, going to the first level makes the buffers not reach the host and the clients. I've...
  14. Alex

    Windows Detritus WIP [BETA, Turn-Based Online MP]

    For the past month or so I have been working on a turn-based platformer with a destructible terrain, much like the original Worms (1995). I wanted to create a small game which had online multiplayer capabilities, a game that does not require an account to play online. I originally had the idea...
  15. KyleRansford

    GMS 2 How to "Reserve" a Controller Slot for Player 1?

    I have my game setup where if there are more than 1 player, they can each use a controller. But, how would I "reserve" a controller slot for player 1? Since the way I currently have it working is, that in 1 player mode, the 1st player can use either the keyboard OR a controller. But, because of...
  16. Pelican Police

    Multiplayer with no portforwarding or server. Only two or more clients directly connecting to each other

    So after seeing that other topic, I decided to test UDPHP. TL;DR, you can circumvent the need for a server if you just connect two sockets together. And holy crap, it works... 99% of the time... But what I'd love help with, is checking how often this works in the real world. Because there's no...
  17. D

    GMS 2 2 player dynamic zoom - Help

    I am working on a 2 player platformer. I want my two characters to be seen in the camera and to zoom in and out according to their x distance //Zoom// Adjusts the camera size perfectly. //Tracking// Centers the camera position perfectly. But both together mess up the centering... Everything...
  18. WimpyLlama

    Questions about multiplayer security and server speed

    I'm making a PVP/Tower Defense multiplayer game in GMS2 and I'm wondering how secure it is. What I mean by that is, if I store something like, for example, how much damage a weapon does on the client-side, is it possible/how easy is it for a hacker to hack the client and change that value to...
  19. Hyteel

    SOLVED Massive lag in multiplayer

    Hi I have been working on a multiplayer system for awhile now and decided to make a server based system where the calculations are being handled by the server. This has caused the lag and response time of the game to drastically increase and I can handle collision server-side this way. But after...
  20. Bukmand

    Asset - Project MMO Engine

    Test the project: https://bukmand.itch.io/mmo-engine-gamemaker-source-code Features: Keyboard press networking send, instead of every frame. Server sided moving enemy. Global chat. Player vs player Coordinations are updated every while if any problem happens. Smart double login protection...