Architecture and foreseeable problems

12 Nov 2023

When I start thinking about how to make it, I can’t help be gravitate towards what are inevitably some pretty niche but interesting problems (interesting to me at least). Even if I don’t end up going any further with this project, I’ll be happy to have a place to brain dump some of this information so it can stop washing around in my noggin while I go on a cycle.

How do worlds get initialised

1. World created at lat/long in the uk
   1. first randomly, later at poi
   2. use poisson disk sampling
2. Lat long converted to geohash (6 characters)
3. If geohash is new to the db then create a new geohash in the geohashes table, along with the bounding box

Updating worlds population

• Have an updater process move forward one tick per second

• There is a datetime column in the world table which indicates next population growth time
• Once per second, the updater process scans the db for any worlds where next population growth time <= current time
• The updater process updates these worlds, and schedules the next update for current time + current population
  • If the population has been updated to 10, then the next increment will be T+10
  • this makes population growth slower and slower and encourages to player to use their armies sooner

How to send updates to the client on moving fleets

When a player decides to move a fleet from one planet to another

• create a new entry in the fleet table with estimated time of arrival, and trajectory
• For each geohash object that overlaps with the trajectory send an update on that geohash channel
• A new connecting client will need to query for the existing status, and subscribe to further updates
  • These could be handled on the same webserver connection where the client can ask for all info related to a geohash, or just the updates

So what i need is

• A postgis database with the following tables
  • Geohashes (or ares of interest)
  • worlds
    • Lat/lng, population, world type (player home or other), maybe description when theres POIs, owner_id
  • fleets
    • start time, end time, trajectory, size, owner_id
  • players
    • owner_id, name, password, etc
• An updater process where once per tick (i.e once per second)
  • Update world population accounting to population growth rate
  • For any fleets that have reached their destination, process that
• A server that
  • Listens for fleet creation, sends those updates to client
  • Updates client of population updates
• A client
  • Player login
  • Tracks player position, feeds home world position to server
  • Lets players make fleets

The updater process and the server process need to communicate somehow, this can be done using postgres notify/listen

• https://gist.github.com/kissgyorgy/beccba1291de962702ea9c237a900c79

Mapbox has support for animating markers

• https://docs.mapbox.com/mapbox-gl-js/example/animate-marker/
• http://kuanbutts.com/2019/08/31/mbgl-vs-leaflet/