How does happiness actually work?

[Horoai]

I very well know the obvious stuff about happiness that the wiki and almost any other website about Banished has to offer:
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Happiness affects productivity. An unhappy population will idle frequently, decreasing overall production. Some structures increase happiness, such as:
- markets
- wells
- trading posts
- cemeteries
- chapels
- taverns - (producing Ale)

Industrial structures such as mines and quarries will decrease the happiness of those who live nearby.

Births and marriages increase happiness, while deaths, sickness, starvation, and freezing will decrease it. A cemetery will reduce the amount of happiness lost when a citizen dies, so long as there is room for a new gravestone.

The more unhappy a citizen is, the longer they will idle for - having very unhappy citizens will lower their effectiveness at their jobs.
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The question is how exactly does it work?

• How does the game handle happiness internally? Is there like a happiness integer and methods to increase or decrease it?
  
• Are there differences in gain or loss between the different structures aside from cemeteries?
  
• If so, do villagers prefer to idle at the best possible nearby structure?
  
• How much + do you need to counter the - of a mine? (example)
  
• How much happiness is each building worth and whats the basic requirement for 5 stars?

I don't think you need all of these structures to keep your people as happy as possible. In my experience a cemetery, a well and a market suffice plus you have to build those anyway. I build chapels for decoration but they never seem nessecary and I haven't built a tavern in several houndred years.

I never build more than two mines and a quarry and in case they infact spread unhappiness to nearby homes their impact might as well be limited by placing them isolated from your main town like foresters/gatherer/hunters.

The size of your population doesn't seem to affect happiness in my experience. I had to fight creeping unhappiness before but that was likely due to minor flaws that stacked up to inefficiency with every new district. Is that why we have more buildings than necessary?

[Banisha]

Apart from the obvious happy places, food variety is a big issue. So are steel tools and warm coats. Distance to access services/foods is another. Long walks chasing things seems to piss them off.

And..... lack of expansion seems to be a factor as well. When I do not build anything for quite sometime it appears they have a "stagnation" factor decreasing happiness.

Taverns are not needed.

Note: Without access to the devs algorithms this is pure supposition - from all of us. Far too much variability to even consider getting a measure on it. We have no controls to work from and the numbers are not fine enough.