Weather in Virtual Worlds

If you get a game designer who majored in literature, they’ll bring a toolbox marked ‘Lit Tools’ and dump it out at the design phase, “Is there anything here we can use?” And then just how helpful that person is depends on the size of their toolbox and how many things in there can be used.

And to paraphrase my co-worker, Reece: Any tool can at least be used as a hammer.

The World knows how weather works, more or less. A monstrously large set of variables collide to produce a result that is just a little bit, but not entirely, predictable. Sometimes it rains, and when it does we know that’s why. It’s nothing personal. The rain falls on the just and the unjust alike. It’s complicated enough that it might as well be random, and weather systems are mostly implemented as random things.

Seasons happen with absolute predictability, and where they are implemented at all, they are implemented just so. More commonly they are tied to terrain – it snows in the mountains and it’s summer on the plains and it’s spring in the forest, forever. And that’s good enough.

The sun rises and the sun sets, and everyone’s figured out that “realistic” nights are too long, so those get fast-forwarded a bit, generally. Still, it’s day when it’s supposed to be daytime and night when it’s supposed to be nighttime, and those don’t have anything to do with what’s going on.

Not like they should. Sometimes there are things that only spawn at night, because we know on an intellectual level that’s how things work. The nighttime beasts come out at night.

That is, we all know on an intellectual level that’s how it works, but we also know on an emotional level that isn’t how it works at all. There’s sad rain and happy rain and romantic rain and ruin. If you’re sad and it’s raining then it’s raining because you are sad. The weather is punctuation for life’s little events. The undead don’t come at dusk, they bring the night with them.

The weather in stories is never random. Which you might take to mean that it’s never realistic. But it actually means just the opposite: It’s more realistic because it maps to our perception of how weather works, rather than mapping to our intellectual understanding of how it really does work. The weather, like the music, must fit with what’s going on.

Likewise for the seasons, and day and night.

You know how a weather system ought to work in an online game?

Total Party Wipe-out makes it rain like hell.

When you emerge from a dangerous dungeon, that’s when the sun rises on a new day.

Clouds gather over fallen comrades, but the sun breaks through when they’re rez’d.

You hear thunder in the distance? You’re in a dangerous zone … something bad is about to happen.

If it snows “because it’s winter” then you still have to answer the question “Why is it winter, now?” Winter is when you are reaching the end of a phase of your life. If you’re a warrior closing-in on level 10 – the level at which you have to make a choice as to what kind of warrior you’ll become – that’s when it’s winter.

Decide to become a Paladin, and hey, it’s spring!

And no, I’m not saying that you should display different weather to two different players in the same place. But you can map the content progression to geography and map the weather to that. So you begin as a level 1 warrior in a town where it is spring, and as you level-up you also move through the world toward winter, and when you graduate from that track and choose, essentially, to begin your new life as a Paladin, then at the place you need to be, it is spring again (could even be the original place you started at).

And a great big thunderstorm doesn’t have to mean that your entire party just died. It works so long as there’s a pile of someone’s corpses around.

Mapping day and night to appropriate events? You could do it with instancing…

But “realistic weather” isn’t realistic. It defies our emotional understanding of how weather works. It’s like choosing random music for a movie. Bad! The sad part needs sad music, the tense part needs tense music, the happy part needs happy music.

Games, too. Weather, too. Even in ‘Virtual Worlds’.