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Ideas for Upcoming Livestreams (Pedestrians & Epidemics)


Hi everyone, I hope you are safe in these interesting times.

Inspired by a post on the subreddit, I remembered how easy it would be to simulate epidemics in Citybound. You might have seen some interactive simulations recently, from the Washington Post article to the very nice and quite a bit more detailed 3Blue1Brown video.

Even in that video, only a simple simulation of people as jiggling blobs is used. It does have crude (but meaningful) approximations of people travelling to shared centres or between communities.

Citybound, however, already has a much more detailed model of what people actually do each day and where they travel in a city - since it simulates every individual going about their daily business, travelling by car to their specific job, home and shops. This makes it well suited for more realistic simulations of the spread of viruses, but also all kinds of other simulations that rely on just having a pretty accurate, detailed model of what people do and where they go.

With my ongoing work on procedural architecture and improving the game UI, I feel like I have been abandoning the simulation aspect for a while and want to try to develop them in parallel. My work in progress code is too much of a mess still, so I would branch out from the last running state of the game and develop new simulation logic there, merging the two later.

Like this, I hope I'll able to develop the new simulation features quite rapidly, while being able to work on more behind-the-scenes stuff more slowly, in the background.

With some preparation, I think working on this should be interesting and fast-paced enough to do some livestreams!

Here's the rough order of things I would suggest to do:

  1. (Warmup) Implement simple dynamics of people randomly getting ill, going through an incubation period and slowly recovering
  2. (Easy) Implement people infecting each other when they are at the same building at the same time (with some probability)
  3. (Serious) Implement pedestrians based on the current car traffic model - this is a huge topic with all kinds of aspects to consider, I'd suggest we explore what we want to do here together
  4. (Easy) Implement pedestrians infecting close-by pedestrians
  5. (Medium) Implement possibility to add social distancing rules
  6. (Medium) Implement possibility for people to choose between going to shops and receiving deliveries

This all sounds pretty focused on epidemics, but I'm sure you can see how this also benefits general game features - like even having pedestrians, or people making more complicated economic/behavioral choices.

As mentioned above, this will take some preparation, especially the implementing pedestrians part. I'm guessing it might take up to a week, but I'll keep you in the loop about the progress and when to expect some livestreams.

Let me know if you would be interested in that, which aspects are the most interesting to you, or if you have any additional ideas for what we could do. Looking forward to hear your thoughts!

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