Story Progression

The Story Progression prototype explored one possible mechanism for simulating a town full of Sims (100–200 was the target) in such a way that each Sim maintained a semblance of “temporal coherence” at the macro level as well as reflecting their progression and evolving state in their moment-to-moment behavior and interactions.

This was based on a “lightbulb moment” where I realized that as you zoomed out of a Sim from small actions like using the toilet, making a sandwich, etc. to higher level actions like getting a job, getting married, you might be able to choose which of those higher order actions happened in the same way that we currently selected using the toilet, albeit at a much lower frequency (hours or days vs. seconds and minutes).

For example, an autonomous Sim in the law enforcement career wouldn’t have to actually study to get promoted. We could just choose for him to gain a skill point from time to time as part of the higher-level simulation. Similarly, the chance of the promotion “action” could be modulated based on the Sims’ current skills and traits.

In many ways, you can think of the whole thing as level-of-detail (LOD) for simulation.

In this prototype, the entire screen represents a neighborhood. The orange boxes are individual houses, and the yellow boxes and little purple and pink boxes are Sims (the latter being children). As the simulation advances, the various Sims are subjected to life events as detailed above, and they progress through life… including buying furniture, upgrading their furniture, making money, getting married, moving to a bigger house.

This image shows the life story or life event inspector. In this window you can select any Sim and see everything that has happened to them so far in the simulation at a macro level—every time they met somebody, fell in love, had a fight, got married, had a baby, got a job, got promoted.

While we eventually dumbed this down a bit in the shipped product, this fundamental model was what ended up in the final design for The Sims 3 and has been carried forward in spirit into future Sims incarnations.