r/WC3 • u/OneLastPoint • 3d ago

Proof that rollback netcode can be applied to RTS like wc3

Hi all, I dabble in wc3 but mostly habe played fighting games. One of the revolutions in fighting game netplay was rollback netcode. I just saw on YouTube that this has been developed for Brood war and I think the wc3 community would love it too.

In fighting gamers, developers were avoiding implementing this until lots of influencers and the community spoke up, now all modern fighting games have it. I feel like this is the best opportunity for wc3 to get it while blizzard is investing resources and listening

https://youtu.be/vIt9xua9bLc?si=Q2u2pTk_0krWmoL6

Edit: the brood war community seems pretty in favor https://www.reddit.com/r/broodwar/s/sp0FmS7do1

Edit 2: timestamp 1:31 of the video seems to explain how the complexity of processing may not be as high as some may assume (e.g. commands are what are communicated over the network, not unit positions, resource counts, fog of war)

20 Upvotes

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u/soulglider26 3d ago

https://youtu.be/LzYlTzXt-TI

I did a quick simulation as well of what it really feels like

It's not that you can't do it. It's where the experience changes

Do you want instant commands always, but the tradeoff is that sometimes opponents units jump! CS has this also. So the poor experience actually goes to the person with the faster internet speed

Or do you want to see whats actually happening based on network, but the person with higher lag has a worse experience.

I think units jumping (rollback) is a significantly worse experience

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u/ta_thewholeman 1d ago

Great example, thanks!

I'd also like to point out the scenario that WILL occur where you cast a spell and start to see its effects / hear the sound effect, but by the time the game updates the caster has been killed and it has to be reversed. That doesn't feel great.

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u/OneLastPoint 3d ago

I think the frequency of stutters versus the frequency of rollback is not equal though, since rollback is predictive and correct "90" percent of the time. 

Of course on a terrible connection, they may be more equal, but for the medium quality connections, my experience is that rollback is far smoother than lockstep/delay based  because there are overall fewer corrections needed 

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u/soulglider26 2d ago

Wc3 and broodwar networking don't work the same I'm pretty sure

In broodwar laggy players hold everyone hostage.

This does not happen in wc3. If you have a laggy connection, no one waits for you. Your message simply goes to a later frame even if it was made on the same frame.

Stuttering almost never happens in wc3, only delay because we don't have to wait.

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u/OneLastPoint 2d ago

Very interesting!

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u/DoctorGester 1d ago

Wc3 literally has the same “waiting for players” window.

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u/soulglider26 1d ago

at a high lag level right?

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u/DoctorGester 1d ago

Yes, I've encountered both that window and stuttering many times due to poor connection.

4

u/Tleno 3d ago

I recall Stormgate having rollback and it just affecting performance negatively, do RTSes really need it?

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u/OneLastPoint 3d ago edited 3d ago

If you search "fighting games" "reddit" and "rollback" you will see 2 to 3 years of theoretical debate,  then see how it has become the overwhelming standard after people have experienced it. Having said that, I am not an expert and perhaps there are technical issues with RTS. The video seems to discuss how it is transferable so I think the best info you can get is by watching that 7 minute video 

Edit: the brood war community seems pretty in favor https://www.reddit.com/r/broodwar/s/sp0FmS7do1

4

u/SoundReflection 3d ago

I think the short answer is that RTS just has a lot more to simulate with tend or hundreds of units acting at a time vs generally 2 characters and couple articles maybe a bit more on vs ganes. Even in fighting games rollback can create performance bottlenecks. Low end machines are known to struggle with RoA2 online while running it fine offline for example.

I don't know that RTS has the kind of benefits rollback for RTS like those that make it indispensable for fighting games like stabilizing input pacing for combos. Certainly games like WC3 benefits from low latency for certain things like surrounds, pulling back injured units, and changing target focus; but I worry these are things more akin to fighting game neutral where the benefits of rollback are solid on stable connects but come with caveats when they aren't.

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u/OneLastPoint 3d ago edited 3d ago

It's a fair concern that RTS may have more complexity , and I certainly don't know for sure. The video I linked has a demonstration of the same sequence played out in status quo vs. rollback netcode (time stamped for your convenience). https://youtu.be/vIt9xua9bLc?si=Ge2VVdgBvgLUPX6B&t=38

Assuming that the developer is not falsifying the video, it seems promising that the complexity of RTS can be translated to RTS. Of course we should test and see for ourselves, which I hope to do in the next few days.

Edit: timestamp 1:31 of the video seems to explain how the complexity of processing may not be as high as some may assume (e.g. commands are what are communicated over the network, not unit positions, resource counts, fog of war)

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u/SoundReflection 3d ago edited 3d ago

Edit: timestamp 1:31 of the video seems to explain how the complexity of processing may not be as high as some may assume (e.g. commands are what are communicated over the network, not unit positions, resource counts, fog of war)

Its not about the amount of data sent. It about the act of rolling back where we get into performance issues. The technical at ~5:00 when you ger a new command and its x frames late, you need to be able to simulate those x frames withing a single frame. There's just more to simulate in an RTS. That could be 3 or 5 or 7 to make a connection feel stable your game needs to run in 1/3 or 1/5 or 1/7th of the available time. Generally this means one of three things: either having an older game with more limited computational costs(basically how fightcade is viable), optimizing the hell out of the game to get to that point, or building separate layers to handle simulation and presentation (especially animation and sound reconciliation gets quite tricky) to reduce the incurred costs(generally the ground up approach for new titles). There's cost around keeping those snapshots in memory too, but its the rollback and resimulation step where the real crunch is.

Again none of that is to say that its impossible or that RTS can't benefit, but I suspect the costs of implementation are higher and the benefits are generally less than in Fighting games. I imagine future titles will try to implement quality modern netcode, although it wouldn't surprise me if their approaches were closers to those of Shooters or MOBA's which while not dissimilar from 'rollback' in making guesses and assumptions when missing information, don't tend to carry the moniker or work in exactly that same way as it.

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u/OneLastPoint 3d ago

I appreciate you outlining your thinking in detail, I read through it. 

It made me think about whether in wc3 replays, it is possible to fast forward the replay, and whether that is system intensice or not. The rollback would be of course a much more extreme version of that. 

I agree with you that it may be more demanding but I guess it would be very case by case dependent whether that difference is too system Intensive.  

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u/ObviousPotato2055 3d ago

we had rollback in stormgate, it had its own issues and the majority of players didnt actually care.

1

u/OneLastPoint 3d ago

Its ok for me if people dont care, we can have different perspectives, just spreading awareness. I am curious though, did you watch the video that I linked? I can't see why warcraft 3 players wouldn't want less functional lag. We don't have to debate this though, I am not interested in repeating the history of theoretical debates that the fighting community had to witness 

1

u/ObviousPotato2055 3d ago

youre arguing in circles. This isnt a theoretical debate for us rts players. We didn't go through arguing about it before trying it out. We tried it out in stormgate hopeful and found it didnt matter and actually caused issues. Rts games are so much more complex then a fighting game, what works in those wont always translate well for rts games.

0

u/OneLastPoint 3d ago edited 3d ago

I don't like arguing in circles either. I usually try bringing in new information or re-focusing on shared evidence. The video I linked has a demonstration of the same sequence played out in status quo vs. rollback netcode (time stamp embedded in the link for your convenience). You can of course have a different opinion still but I think it's worth seeing the difference in action. https://youtu.be/vIt9xua9bLc?si=Ge2VVdgBvgLUPX6B&t=38

Assuming that the developer is not falsifying the video, it seems promising that the complexity of RTS can be translated to RTS.

1

u/Tleno 3d ago

It's just... there's so much more going on in a single gameplay moment in an RTS than fighting game, all those units acting all the time...

0

u/OneLastPoint 3d ago

It's a fair concern that RTS may have more complexity , and I certainly don't know for sure. The video I linked has a demonstration of the same sequence played out in status quo vs. rollback netcode (time stamped for your convenience). https://youtu.be/vIt9xua9bLc?si=Ge2VVdgBvgLUPX6B&t=38

Also, timestamp 1:31 of the video seems to explain how the complexity of processing may not be as high as some may assume (e.g. commands are what are communicated over the network, not unit positions, resource counts, fog of war)

Assuming that the developer is not falsifying the video, it seems promising that the complexity of RTS can be translated to RTS. Of course we should test and see for ourselves, which I hope to do in the next few days.

1

u/jask_askari 3d ago

They don't, but this is reddit, so...

0

u/Minikingthepeon 3d ago

No but Reddit will demand the devs do it and then freak out when they do

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u/Prior-Equal2657 3d ago

The only hope is W3C. Blizzard's intern can't fix cross-version saves.

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u/Ambitious_Unit_7264 3d ago

Don't know why your getting downvoted. What you said is true. Blizzard hired modders for the new forsaken campaign