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Comment by angrais | Hacker News Reader

Could you explain how world of Warcraft works then? You can certainly have more than 200 in one place at once... Are they doing some tricks to make this appear as if it's working but in reality it is not?

Would love to hear your opinion.

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In WoW players don't collide with each other. Every player is really just a point and a facing. There's no collision detection with spell shots. Of you're within range and LOS, you can cast the spell. And once the spell is cast it doesn't collide with objects.

Basically, WoW gets around it by vastly simplifying player interaction.

> 200 in one place

200 players in one map instance.

But not 200 visible player with interactions refreshing on real time. Most likely you see diminishing level of details, if anything besides complete fabrication or no data at all after a certain visibility range threshold.

The spiffing Brit managed to get 500 people into a single Factorio game, not all visible at the same time but all interacting with the environment. It was an interesting video, the performance was fairly good.

I saw that video, the game definitely struggled.

It's certainly doable though.

Buildings are more CPU intensive than players unless those players are all busy fighting. If they just mine or place buildings they simply don't matter.

This doesn't really matter though, after a certain point there isn't much difference to players between 50 people and 200 people within visible distance. You can just stop showing others past some cap, or throttle position updates to like 1 every 20 seconds or so and fill in the gaps with AI.

Actually it makes a huge difference. You haven't played WoW have you?

To the people downvoting me, I only said that because his response was directly about somebody mentioning World of Warcraft. In WoW, if they only limited you to seeing 50 people the game would feel completely different when you go into cities and do open world PVP and such. It would literally break the game.

In fact when they released WoW Classic they had a new technology they called layering where even if you were in the same realm as somebody you could be on a different layer and therefore not see them. People absolutely hated it and went crazy.

So that is why I asked him if he had played it since he said "at a certain point there isn't much difference to players between 50 people and 200 people within visible distance" which is just wrong.

On HN to uphold civil discussion it’s best to avoid dismissive references and assumptions directed at “you”. Best to address the idea alone with your example/argument, rather than the imagined speaker. Otherwise it can be interpreted as needlessly antagonistic and will be downvoted.

That's fair

It's an open world game, but let's assume you mean local map.

In that case, let's assume that each player waves (/wave). I've done this before with >50 players and took a screenshot and we were all in sync. It's also possible to have 50 players in the same area fighting in real time, e.g., in a battleground. This was back in 2010 when I played ... So I am not sure if it's any fabrication at all, otherwise everyone would die, etc? Given players have health, take damage, get healed, etc.

This is one of the reasons it's been so believable. Lots of people think they've already seen it, apparently. The gap between what MMO players already think they're seeing and what these founders are promising seems trivial, but actually implies a lot about network latency and bandwidth, software complexity, etc.

Ultima Online could do 100+ visible people back in 1997.

But I don't believe WoW could do it now, the last time I played WoW, early last year, in a large raid, there would be spells cast from invisible people because the characters wouldn't even load.

The lag around the Britain bank when busy (even sometimes Moonglow bank) made it nearly unplayable though, and the game was only 2D.

I remember on a player run server (Novus Opiate) we had a random battle one day of red vs blue and we had about 80-100 people in Britain run through a portal into Buccaneer's Den, slaughtering all the reds, and all the reds banded together to kill the blues. It was well over 100 people with minimal lag, with most people on 56k modems.

But Britain bank with lots of people was always laggy. Especially if there wasn’t a server reboot in over a week.

Maybe all players where in sync because of tick granularity.

In Eve online the largest battle had ~6500 players concurrently. Eve has a system called time dilation to help handle large fights. During a normal battle, every player's actions are processed by the server, and the state is sent to all players at least once every second. When there are too many players and actions for this to happen, the servers overall tick rate slows down. So for this fight time dilation was down to 10s per tick, everything takes 10s as long, a normal weapon that fires every 15 seconds only fires once every 150s. Even with this 10x slowdown of actions, and a game like eve where relatively few actions are taken by each player there is a huge amount of lag, the server and clients don't always agree on the game state, weapons not activating, commands not being recognized.

The underling issue here is the information needed scales exponentially with the number of players interacting. Supporting 200 players means 400x as much information as 10 players instead of 20x as much. So specifically for WOW, there are problems with more than 80 or so players at once in PVP. If you do things like large scale open world PVP getting desyncs, disconnects, heavy lag is common. Also for major cities and other high density areas most servers have 4 or more "phases" where you can be in the same place in the game and not see other people not part of your phase. So you could have 50 people in a guild all together, 200 people in local, but most of the other 150 in another phase.

Nit: that is quadratic scaling, not exponential

WoW's servers fall down pretty hard if you have 200 players in one spot doing more than just running around. The Ashran battleground was lowered below 40v40 for a while because even just that many players fighting each other was enough to get multi-second lag on abilities.

Back when I was playing capital city raids would lag out pretty badly - you don’t get it when everyone is massively single-playering but when action is occurring you notice it.

Not an MMO dev but my random guess is that there's not a lot that needs to be directly p2p. I've only played FF14 but most of the interactions you have don't require you to have precise locations of your party. Server has a tick rate and for mechanics you need to be aware of server latency. Most everything can be calculated server side and/or predicted. Many abilities often have a cast time which can be used to hide latency between clients.

Unless you are playing on console, almost nothing is p2p in gaming (Due to cheaters). The server has to simulate the entire "world", and as I understand it, the problem becomes when you have one server instance simulating a world for 100s of players.

The said, FTA I think people are focusing on the wrong side of aisle. From what I understand, I don't think anything they said is impossible; it just seems like the team is very inexperienced and MMOs are incredibly complex and given how few MMO developers there are (MMOs are popular, but they aren't diverse) they might have bit off more than can chew. I'm really not seeing how what they are trying to do is anymore complicated than Fortnite or Minecraft from a backend standpoint (I'm very green to game programming)

player to player, not peer to peer

The WoW world is not very mutable unless something big has changed since I last played it. The amount of state to be managed is small. It’s basically location, inventory, some ephemeral projectiles, etc. Only a small number of players can see each other at the same time too, so it’s not like thousands of people in a virtual colloseum.

If you've ever played sitting next to someone else, you'll notice that not every animation is shared, just position and future position. If you hold the mouse button and spin in a circle, it won't show on the other person's screen. And the spells aren't governed by the animations position, but rather calculated and animated as a "hit" or "miss" completely independently on the other person's computer.

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