Comment by whartung | Hacker News Reader

Comment by whartung | Hacker News Reader

Speaking about WoW specifically, since I'm not familiar with the others, I've always been curious about their quest system. Specifically keeping track of what are available for the character efficiently along with the event system to flag quests as completed, etc.

There's so many of them. I have to assume they're spatially limited. You enter a zone, or an area, and the system loads up all of the quests located in that space, then it runs through to determine whether you qualify for them.

As for quests that you're on, that's a bit more straightforward, since you're so limited to how many you can carry around with you at any one time. Then, every event can practically just be brute forced across your pending quests to see which ones get progressed, etc.

But it was always a curiosity to me considering the magnitude of the quests available how most anything can trigger quest progress.

There's also the whole achievement system, which perhaps is similar in design.

> Specifically keeping track of what are available for the character efficiently along with the event system to flag quests as completed, etc.

This is not necessarily that difficult, at least the first part. A lot of games will have quests be given out by a 'quest giver' character of some sort, or they will activate at specific interaction points on the map. You can do some cheap 'has-player-finished-quest' type of checks to determine if for example the quest giver has some sort of UI to indicate they have a quest available that activate when the quest giver first comes into view range. Quests with more initial conditions can hide their checks behind the interaction with the quest giver.

Doing quest progression can be a bit more challenging. You need to determine when to do the checks for progress, and also how comprehensive you want them to be. The more complex the check, the less often you can run it without affecting game performance. I've seen designers use all sorts of tricks depending on the specific quest. Interaction volumes that run checks, periodic ticks, on entity flash messages..etc.

> Then, every event can practically just be brute forced across your pending quests to see which ones get progressed

This only works for games that have a small number of active quests and not a lot of events. And with MMO's, you really need to be considerate of the accidental quadratic performance problem.

Sorry in advance for not answering right to your question, but you may check sources of ManGOS/TrinityCore/family WoW servers for that.

In short, from what I know, yes, quests are stored in "quest log" fields of character data in server DB, and they are tracked by the clients and checked by the server. Some simple auto quests like "find this item" are not even tracked by server and only stored on completion. Since both client and server have all game data, the client knows about all possible quests and only shows to the player what is appropriate at a current state.

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