It's been a long time, but we had a few goals:
Go to full 3-D. At the time this was a hugely ambitious goal—we even wrote our own 3-D engine!
Add longer-term goals. These became "aspirations" that drive the Sims' long-term behavior.
Add situational awareness. Sims would be more responsive to what was happening to other Sims. As I recall, we did a lot less with this than I would have liked. That actually drove some of my own AI research later.
Add longer-term relationship values. A Sim could be angry with her spouse without "falling out of love."
Add more meaningful jobs and locations. This eventually came out, sort of, in later releases, but a ton of work we did for this was dropped. For example, we had game play for creating your own doctor's office with waiting room and treatment room. The more chairs, magazines, fish tanks, etc., the longer patients would wait. The worse the diagnoses or procedures, the faster they would leave. (If you made the patient scream because you chose the wrong procedure, the Sims in the waiting room would get upset and run out the door.) Unfortunately, we were also beset with frustrating technical issues involving the underlying scripting language (Edith), so making all this was incredibly difficult.
Make the environment adaptive based on the player's decisions. This is probably my favorite thing that didn't make it in: We wanted to vary the lighting, camera angles, and music based on the kinds of objects the players purchased. So if you bought a bunch of creepy things versus hearts and flowers, we'd use lighting, sound, and view angles corresponding to a horror movie versus a romance. Among other things we were able to show was that the same animation of two Sims kissing looked and felt very different when set to romantic violin music versus smoky sexy jazz music. (One exec who watched the two sequences said the jazz one had a lot better resolution—but it was literally the same video of an animation in both cases.)
The biggest problem we hit early on was that the first version of The Sims just kept on selling. It stayed in the top 10 far longer than anyone expected. And then the expansions came out, and it sold even more. That gave us a lot of time to work on different things but also made it difficult to sustain a big team on the project. We lost a few of our people, and I eventually went on to work on Ultima Online myself.
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