openttd
I downloaded OpenTTD on Android and started a subtropical climate game. It's 1980 already and I still don't have access to the electrified railroad construction.
I read on the wiki that there are no electrified vehicles in the desert climate. How to add them?
This occurs because it takes time to load: proportional to the amount you are loading. When the first ship loads up, it leaves less for the second one to load, causing the second ship to spend less time in the dock, and therefore catch up to the first. As the second catches up, there continues to be less and less for it to load, causing an accelerating cycle that ends up in the state you have pictured.
The best way I have found to combat this is to make all (or all but one) of your vehicles wait until fully loaded. This causes less available cargo at the dock to mean more time at the dock. This reverses the cycle and causes your vehicles to remain relatively well spaced.
The a single vehicle on the route not fully loading will not cause this problem, as it will eventually catch and pass the fully loading vehicles ahead of it. Such a vehicle can be a good indicator of when you need to add or remove vehicles.
Update: After examining in detail a function on line 2166 of town_cmd.cpp, it is my opinion that the town chooses the building completely randomly based on two factors: the tile's "status" (which just controls whether a tile is 'available' for building on) and the town's "radius group". This is also corroborated by my experience in-game, which is that towns will build different types of houses based on how big the town is and which 'ring' the tile is in. Hopefully this is what you wanted, but I'll preserve the rest of my answer in case anybody else finds it useful.
Update 2: After reading your comment, I feel compelled to point out that the below paragraph should answer that question (on road access). Having said that, I'm a bit confused since I've never experienced the problem you're referring to - admittedly I greatly prefer "original" layout over 3x3 grid; perhaps it's simply my lack of experience in 3x3 grids that has caused the greatest amount of confusion in regards to this answer - for that, and the lack of organisation/coordination in later editions of the answer, I apologise.
It is my belief that for a square to build it must have road-access (otherwise the town will build a road for it), 'road-access' is defined by a road within 2 squares (ie an adjacent square must be a road). There is no particular way to build roads that will encourage or discourage building on a particular square - the town requires it, but will build the roads itself if necessary. There's no way to "force" a town to build in a particular square.
If you disallow town road-building, you will need to fill in road access according to the above rules in order for a square to build (road within 2 squares).
The old (fairly off-topic) answer:
I've played the game for a number of years now, and probably can't offer anything more definitive than said sources but I'll give it my best shot anyway.
The bit in bold is there because it is the factor that keeps cropping up in code, and I think is the most important factor in growth. If the town has not reached its goal, it will not grow (unless you are funding its growth).
Also worthy of note: funding a town twice in a row doesn't appear to be economically-sensible. It seems the town will be funded for growth for the next 3 months at the point you fund it - funding it again will not increase this to 6 months, it stays fixed at 3 months. The second funding is, therefore, wasted. (this is according to my interpretation of the source code)
The following factors affect whether a square will be built on [source confirmed]:
According to the code as I've read it, these are the only factors affecting whether a specific square will be built on or not. As for when a square will be built on, see the rest of my answer about town growth rate (a much more complicated topic).
The following factors affect how quickly a town grows:
The following things appear (to me) to be a placebo affect at best:
The following factors definitely have nothing to do with town growth (but are worthy of note since many people think they may help/hinder):
This answer is meant to be comprehensive but may not be exhaustive. I will come back and improve on it later on, when my girlfriend lets me play again (something about "becoming obsessive"... I dunno what she means, I mean 10 hours a day is healthy... isn't it?)
Best Answer
In the default game, the subtropical climate only gets access to steam, diesel, monorail, and maglev locomotives (only the temperate climate gets access to electric). In order to get electric locomotives, you need to install a mod (known as a "NewGRF").
In the desktop version, the easy way to install NewGRFs is to click "Check online content" from the startup screen, pick a suitable NewGRF ("2cc TrainsInNML" is probably the most popular, providing over a hundred real-world locomotives), double-click the name or click the tiny little checkbox to the left of the name to select it for downloading, and click "download". Once downloading is finished, click "Close" to exit the online-content dialog, and select "NewGRF Settings" from the startup screen. Find the NewGRF you just downloaded in the "Inactive NewGRF Files" list, click "Add", and then click "Apply Changes". Close out of this dialog and start a new game.
If you're using the 2cc trains, you'll probably want to restrict which trains are available -- the full set is rather overwhelming. To do this, click the "NewGRF Settings" button, highlight the "2cc Trains In NML" entry in the "Active NewGRF files" list, and click "Set parameters". Scroll down and select the regions that you want to use trains from.
I don't know if this applies to the Android version, but I assume it does -- modding is a major part of OpenTTD.