We all know SimCity has bugs. Some of them are more serious than others. But I've found and reproduced one that I think might be the most game breaking and potentially the cause of a lot of other apparent weirdness and inexplicable problems cities seem to suffer.
Obviously, it's possible other people have found and already know about this bug. I'm not one for spending hours trawling every forum looking to check (or rather... I'd prefer not to. I lose hours if I get distracted reading threads). But I did the best I could to properly reproduce it and I took pictures to show it, so now there's no reason not to make a fancy thread.
The short version
Sims commuting to school in other cities via high school buses, or to work/shopping in other cities via regional buses, get 'lost' and never return. Unconfirmed if the same applies to commuting by single cars.
The long... really long version
Here comes a lot of images! Lets start by setting up the obvious test scenario for the school buses.
The first city is the one students will be commuting out of. There's five blocks of residential, one block of commercial (the block with no students in this image, obviously) and some industrial and service buildings. First, to check its all working right before adding the second city, I added a grade school with more than enough capacity.
Here's the population tab, showing 268 students and the 350 school desks.
... here's mid school commute, with students walking to bus stops and being picked up...
... and now all 268 students are in school.
After the school day, all the students make it home (eventually... it takes until 9pm because of the 'first house' simulation. Dumb, but not what we're here for). This all seems to be working fine. So now lets set up the other city with the high school.
BONUS BUG: I built a clinic in both cities to make sure no-one died while I was testing. While I was setting up the high school city, the ambulance from the other city came 'to the rescue', but I had never shared it on the regional service sharing panels. Probably also explains why in a different game I was playing, a random extra fire truck, of a kind that didn't exist in the region, turned up once.
Here's the high school city in its school day. All its students successfully made it to school and there's a wealth of extra desks. Now lets go back to the first city.
In order to encourage the students to commute, I demolished the extra classroom space from the grade school. For some reason that also caused four students to suddenly become uneducated again. Let's not worry about that...
School commuting time again. At the highway entrance, you can see the high school buses from the other city arriving to pick up students.
Here's a high school bus returning to the other city with students on board.
... and eventually all the students commute. The grade school gets filled to its now lesser capacity of 150 and all the rest of the students are picked up by high school buses and shipped to the other city.
BONUS BUG: Somehow, a single student hijacks a high school bus and returns home at 2pm, an hour before school finishes.
Students are commuting home. By the time the high school buses appear from the other city, the 150 students from the grade school are already home...
And here finally, the big bug presents itself. It's now midnight, long after the high school buses have unloaded and returned to the other city. Now can you see the problem? Some of the residential houses have no students in them. Less students exist than there should be and they never reappear. The regional commuting has somehow 'lost' them.
Here's the population view of the same thing. You can see that the same houses are missing the purple students bar here too. So lets run this for another school day...
School commuting is going on again...
BONUS BUG: At the top of this image, you can see a grade school bus out on the region highway. Grade school buses don't operate between cities unlike the high school ones, so it has no reason to go out there. It drives to the edge of the map, reappears on the opposite lane and drives back into town.
BONUS BUG?: While the school commuting is happening today, the grade school never reaches its capacity. But the game seems to want it to, because as high school buses reach the other city, students magically warp home and start reappearing in their houses. They do this over and over, until the buses stop driving for the day, with some students ending up never making it to either school. Also that one hijacker student turns up at 2pm again.
And here's how it looks at midnight after the return commute. Firstly, if you're wondering why the purple bars are in a different place now, it's because most of them visited the park at the top of the map before returning to the nearer houses. But regardless of that, there's the much more important second fact for the big bug: there's now even less students in total, with more empty houses. More students get lost in the regional commute every day.
A bug to end all bugs
Way back up this post in the short version, I mentioned that this not only happens to students but with worker/shoppers too. This is much harder to prove. Workers have night shifts, so they are never all at home at any one time. Shoppers only are distinguished as such while they are shopping and when they return home they become generic population again. But here's what I observed while running a similar test setup where the second city had much more commercial buildings than the first, with regional buses to transport the commuters:
- The city seemed normal before adding the second city. All of the commercial buildings sold out of product every day and the shoppers returned home making most of the city have the 'there's good shopping around here' thought.
- After adding the second city, there seemed to be many fewer shoppers in the streets of the first. It appears most were commuting and don't get highlighted as shoppers while going to a bus stop.
- The commercial buildings now never sold out. Most of them seemed to never have a single shopper visit.
- The buses returning from the second city almost always unloaded to one bus stop, meaning only the houses nearest it got happiness from the returning shoppers.
- Houses in other areas started to have the 'can't find anywhere nearby to shop' thought, despite being right next to commercial buildings that still had product.
- Some houses in the city had no adults (that is, non-students) in them for long periods, possibly longer than a whole day of game time.
My suspicion is that much the same thing happens to commuting shoppers on buses as students; they get 'lost' over time. In another city I was playing before, I had large apartment building that were complaining of needing shopping, which when I watched the shopping overlay, were actually never sending out shoppers at all.
Summing it up: What?
So yeah... it looks like a big one. I've yet to determine if the same bug happens even with individual commuters in cars, but I think its safe to say that any region with a bus terminal or high school risks being hit by this, and that it might explain the majority of those times where you see random buildings saying 'no shopping' or possibly even 'no money'. It is possible that if both cities are being played at the same time, the problem might be mitigated somewhat, but that too is difficult to prove.
Spread the word... um, please?
I mentioned earlier, I'm not one for reading lots of forums. And maybe from my post count, you can tell that I'm not one for posting much either, nor do I have twitter or whatever. I'm going to make a shortened post on the EA bugs forum, and link to this thread, but if anyone out there would care to spread the word further, such as to Maxis dev twitters and the like, it would be appreciated.
At very least, tell your friends in whatever regions you play. Beware the high school and bus terminal, for that way lies ruin.