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Every game has ways to monitor and add gameplay at the right times. Interested in how sandbox game events differ from traditional linear ones? PART 1 looks at the Event Gameloop.

Nathan Cheever, Blogger

April 15, 2019

4 Min Read


Every game has ways to monitor and add gameplay at the right times. Interested in how sandbox game events differ from traditional linear ones? What follows is how I’ve approached it. 

I’m using Quest instead of Mission to separate it from military terms and expectations. It’s also more scalable. A special callout to Alex Cox who helped sort this bigger picture a few years ago.

Part 1 – Managing

The idea of how a game cycles through different features can apply to several topics. For this discussion, it'll center around non-linear sandbox experiences. If the conditions are right, the game will introduce new events to the player or remove existing ones to shape the gameplay.

World State
The current conditions of the game influence what appears in the game. Some examples of these conditions are quest status, player health, and time-of-day. The World State is a storage cabinet for all sorts of values. Monitoring these allows the game to present the best choices for what appears next.

The World State keeps track of what’s in the game pantry

State Manager
Any number of events or Quests can be available at one time. The State Manager is the gatekeeper to all these possible events – a binary flag for “Can this happen right now?” Every sandbox game needs a gatekeeper that manages wholesale chunks of the game.

The State Manager is what’s on the menu

For example, when Batman is introduced to the Riddler, it unlocks a batch of Riddler Puzzles in Arkham City.

Game Director
When an event becomes unlocked, it might not be present in the game world.  Sometimes you need more than blunt ON or OFF. Consider this the keymaster allowing only fresh events to appear depending on what’s recently happened in the game.

The Game Director wants to give you specials

For example, if the player just encountered a robbery, the Game Director knows not to immediately create a new theft opportunity. Another example could be limiting when Lois Lane appears at the Daily Planet... only between her work hours 9am-5pm.

Each event has conditions it must meet before the player is allowed to interact with it. The game checks to see what’s going on around the player (World State), allows a type of event to appear (State Manager), then picks the best one for the moment (Game Director).

Gameplay Events
An event can be as grand as a story arc or as basic as finding if Molotov Cocktails are in a rundown cabin. Working together, the State Manager and Game Director decide what you get to play. Hopefully they pick exactly what you want right before you know you wanted it.

If done right you can end up with a satisfying experience!

The World Event Loop

With all the major parts known, you can trace the game loop for handling open world content. Imagine all the game encounters you've experienced and see how they could appear based on these checkpoints.


In Part 2...

We’ll look at the full spread of Quests & Activities.

  • Quests – a hand-crafted series of events, the corner stone to any game.

  • Activities – a semi-dynamic event, usually repeatable, and spotlighting a game verb.

Motivation Loop details can help you shape to player goals.

  • Core – exercising the most common game verbs in a series of encounters, like combat.

  • Meta – long term rewards for repeat success, such as upgrading your home base.

  • Impulse – immediate gain or loss, low impact in the larger picture, such as looting.

Other topics such as when events can appear will also be discussed.

  • Permanent – always available (after unlocked and before being completed if finite).

  • Conditional – based on situations, such as time-of-day.

Continue to Part 2...

Other Orchestrating Gameworlds articles: Prefab Primer
You can find more posts on my website at CuriousConstructs.com.

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