Unreal Engine 4 Tutorial: Saving a Game State

[@Aimbok]

A longshot, but in case you see this... do you have Discord by chance? I've done this sort of thing for save files before. But would it work in the context of using it for rollback netcode and rewinding frames? That's what I'm currently trying to do, but little things (like velocity being preserved between rollbacks) and other things makes me wonder if this is a feasible path to go down.

[@NebulaGamesInc]

My channel is small haha not a long shot....I see ALL the comments 🤣 unfortunately I don't have a discord. However, anything you want to "save" you simply have to logic through the process.... tell the save game object to save the info whatever it is, velocity, location, power ups etc and then when you re-initialize the game you use that data to re-create all your actors in the exact same state you left them. All the data you would need for that you have to tell the computer to store in the save game object. It's not a complicated principle but executing it efficiently is where the art of coding comes in. Sadly, can't help with that part. If you've noticed all my tutorials are years old. I mainly just provide support for the channel's current content and any random people that stumble across my content and have questions. Hope that helped somewhat 🙂

[@Aimbok]

@@NebulaGamesInc Gotcha gotcha. Ok just a simpler question then: Currently I have my game state remembering what the velocity and the position were of players. But when I tell it to teleport them back to where they were... they preserve their momentum from BEFORE the teleport. Or at least they seem to do so. I even zero out their velocity before applying their old velocity and it still feels wrong. A basic basic example of this, is if you do a set actor location into the sky, you KEEP building acceleration from gravity the entire time. So you have to keep teleporting faster and faster to avoid landing on the floor. I assume I just HAVE to do some hacky trickery, like zeroing out velocity before teleporting? Or telling them they've landed for a frame? Maybe it's just an illusion and they ARE having their velocity set properly currently, but it just feels like something is wrong. Also do you know how to make collision deterministic? Obviously in a multiplayer game that wants to rewind in time, things MUST be deterministic. And it feels like I bounce off the other characters hitbox randomly (maybe framerate dependent)?

[@thebigjoe1123]

hey i just saw this i have an actor with three different childs but it dosent work for me, i will appreciate if you help me out

[@NebulaGamesInc]

What's the issue?

[@marcusbarlow7160]

Thank you, was doing my head in working out to permantly remove items from a game. They kept respawning. Wish I had of seen this video a week ago.

[@NebulaGamesInc]

Haha you're welcome.

[@megtwin]

Does this system work even if you go to another level and come back?

[@NebulaGamesInc]

Yes. When you open a new level the game state persists but the level will be newly instantiated

[@megtwin]

@@NebulaGamesInc Thanks

[@megtwin]

@@NebulaGamesInc Is there any way to see what you have in the beginning of your GameInstance?

[@NebulaGamesInc]

What part are you trying to figure out exactly?

[@megtwin]

Nebula Games Inc Nevermind I went a different route.

[@OldNickIronSide]

(I used a translator.) Hi. I succeeded in save and load items in the level while watching your video! But there was a problem. .. I made other items and put them in, but it doesn't work properly. I made a structure file called ItemData and made it with HP Potion, Oil, Food, and so on. It worked well when I did one thing, but I added another and I worked on Grim_Reaper and Level blue Print and it was messed up. I don't know what's wrong. Help!

[@NebulaGamesInc]

Would have to see your blueprints to really help. Send a link using blueprintue.com or something

[@OldNickIronSide]

@@NebulaGamesInc I posted it on "blueprintue.com." Three (Wayne) in front of the title. Tell me if you need anything else. *But this is a wrong blue print, so how do I delete it later?

[@OldNickIronSide]

Could you tell me why it's not working? Still I don't know.

[@NebulaGamesInc]

Still waiting to see your BPs you didn't copy the actual link just the website so I can't see your stuff

[@OldNickIronSide]

These three links... I've only been studying Unreal for a month, so I'm not sure if I can link them like this. blueprintue.com/blueprint/m1aorrsb/ blueprintue.com/blueprint/it3407jt/ blueprintue.com/blueprint/za7zgzgj/ There are some parts that are not connected in some parts, and if you connect them all, the result is the same.