Ok, i will try your suggestion and push 4 villagers in corners. I thought center was defined according to doors positioning only.
The center of a village is defined by valid doors, or more precisely, valid houses. For a door to be a house it must have more sky access within 5 blocks on one side, and it must be detected by a villager. If you build a house with no villagers around, it's not actually a house, it's just a door with a roof on one side.
When you move a villager within 16 blocks of a door with a roof on one side, and the villager detects it, then it becomes a house (and a village). If you move the villager away (out of the 16 block detection range) it will become a door again. The process is pretty quick. Usually only a few seconds are needed for a door to become a house or vice-versa (I believe the maximum time involved is only 6 seconds).
So when all your villagers congregate in the NW corner, as they tend to do (especially at night), then all the "houses" more than 16 blocks away to the SE are in jeopardy of becoming doors again (which, as I said above, happens pretty quickly). This is why your golems spawn outside the trap sometimes. Your village center is shifting around depending on where your villagers are and which doors they detect at any given moment.
If your goal in placing all those extra doors was simply to make more villagers to trade with then that's fine. If you wanted more iron, then most of those 184 doors are wasted effort. You only need 21 doors and 10 villagers for golem spawning (however, if you want your villagers to breed to make the 10 needed, then you need 29 doors). Any more than that is redundant. More doors does not increase the rate at which golems spawn, it only increases the maximum golems allowed to spawn in a village. In an iron farm where the golems are trapped and killed quickly it makes no difference (21 doors or 210 doors will give you the same amount of iron per hour).
If you want to increase the rate at which golems spawn, then you need more villages, not more doors.
Here's a picture of a combination iron and gold farm I built in one of my worlds.
It has 6 villages separated by 66 blocks horizontally (the minimum needed to prevent merging) and 70 blocks vertically, with a Redstone Jazz pigman spawner in the middle. It's not a monster iron producer like Tango Tek's Iron Titan, but it gives me more iron than I need in SSP, and would probably be enough for a small server (I also get a little gold and rotten flesh as a bonus).
Of course, for trading my design above sucks, because the villager pods are inaccessible. When I made the underground iron farm in my more recent world I remedied that by making the villager pod wrap all the way around the golem trap area (like yours does). I also made it tilled farmland with a carrot crop and made sure one of my starter villagers was a brown-coat farmer class (farmer, fisherman, fletcher, shepherd) so that I only needed 2 villagers to start, and I could let them breed unattended until I had enough for golems.
In theory I could increase the number of doors in this farm to 80 while still only using 4 sky access blocks, and that would give me twice as many villagers to trade with (28 vs 14), but I was really only looking for Mending, which the guy right next to the entrance door has, so I'm happy.
You didn't have to post tutorials about valid houses and 10 villagers per 1 iron golem, i know these things. I didn't know that village's center is related to (average?) position of all villagers.
Let me ask something off-topic here. I have 35 villagers now and there are a lot of leatherworkers, clerics and black aprons and not even one farmer. I have other brown villagers but i need farmers. What can i do beside giving them food to spawn more villagers?
It's not related to the average position of the villagers, it's the geometric center of all the valid houses, it's just that a door needs a villager to be a house. You could put 32 of your 35 villagers in one corner, and 1 each in the other 3 corners, and the average position of your villagers would be heavily skewed toward the 31 villagers, but the village would be properly centered on your golem trap. It only takes 1 villager to validate all the doors within 16 blocks (note that they can also detect doors up to 3 blocks above and 5 blocks below).
With 184 doors you should have 64 villagers (provided they are all validated as houses), so as long as they get fed, or you keep trading with them they should keep breeding up to 64. Farmer class villagers include the Shepherd, Fisherman and Fletcher as well as the Farmer. Any of those will farm crops and feed other villagers for unattended breeding (of course you actually need crops, which I didn't see in your pictures).
If you actually need a "Farmer" villager, then you just need to keep those villagers frisky by feeding or trading with them (or plant some crops and let the other brown coats do the feeding).
One other thing, the vertical center of the "village" is defined by the blocks the doors are placed on. Since we don't have a "door" emoji/icon on this forum, I'll use red blocks for door blocks (top/bottom)
If all of your doors are on the same level, then the gap between the cobblestone and the red block above it would represent the vertical center of the village, and golems can spawn +/- 3 blocks from that. So for two spawn floors you would place them like this.
From what I can see in your pictures it looks like you only have a single spawn floor. Adding a second one should get you a little more iron, since you would have fewer missed spawn attempts.
So, to potentially gain farmers, i have to feed only brown villagers?
Unfortunately it's not that simple. Villager breeding is random. The type of baby villager born has nothing to do with the parents. Any pair of villagers can have any type of baby villager.
Another option beside continuing to breed villagers in your iron farm would be to build an infinite villager breeder. Infinite breeders are the best way to get exactly the villager you want, say a librarian with mending for 10 emeralds, but you will also need a lot of automated farms to generate the goods you'll need for trading with the villagers.
Can i force them to go to a special place at sunset when they usually run into houses?
Not really. They're pretty stubborn and it's hard to make them do what you want them to. If you really want to control their movements, you can put them into minecarts. Otherwise, the best you can do is keep them out of places you don't want them to be; you can't really force them to go to any one particular place. Due to the way their positions are calculated, they do tend to prefer the northwesterly direction and, over time, will tend to congregate towards that side of the village if they are able to wander freely, but this is not very precise or reliable.
So, to potentially gain farmers, i have to feed only brown villagers?
No, you can toss in food to the villagers in general and they will share with each other and breed. But a given number of doors has a hard ceiling on how many villagers can be bred in that village before they simply stop emitting hearts and making babies. So if you've got a bunch of un-wanted villagers or villagers with unsatisfactory trade prices, get rid of them. Move them out to a distant holding area (more than 64 blocks away from the village edge) if you want to save them for use in a non-trading village for iron production only, for example. Or simply toss them into your iron golem kill mechanism, through a portal into the nether, or some other place outside the village where they can be killed without hurting your village reputation. Keep a few well-fed villagers inside your village and they'll breed up replacements for the missing villagers.
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"I think I'm starting to like this `programming' thing. It's about four times as fun as shaving." -- Notch, June 12, 2011
The center of a village is defined by valid doors, or more precisely, valid houses. For a door to be a house it must have more sky access within 5 blocks on one side, and it must be detected by a villager. If you build a house with no villagers around, it's not actually a house, it's just a door with a roof on one side.
When you move a villager within 16 blocks of a door with a roof on one side, and the villager detects it, then it becomes a house (and a village). If you move the villager away (out of the 16 block detection range) it will become a door again. The process is pretty quick. Usually only a few seconds are needed for a door to become a house or vice-versa (I believe the maximum time involved is only 6 seconds).
So when all your villagers congregate in the NW corner, as they tend to do (especially at night), then all the "houses" more than 16 blocks away to the SE are in jeopardy of becoming doors again (which, as I said above, happens pretty quickly). This is why your golems spawn outside the trap sometimes. Your village center is shifting around depending on where your villagers are and which doors they detect at any given moment.
If your goal in placing all those extra doors was simply to make more villagers to trade with then that's fine. If you wanted more iron, then most of those 184 doors are wasted effort. You only need 21 doors and 10 villagers for golem spawning (however, if you want your villagers to breed to make the 10 needed, then you need 29 doors). Any more than that is redundant. More doors does not increase the rate at which golems spawn, it only increases the maximum golems allowed to spawn in a village. In an iron farm where the golems are trapped and killed quickly it makes no difference (21 doors or 210 doors will give you the same amount of iron per hour).
If you want to increase the rate at which golems spawn, then you need more villages, not more doors.
Here's a picture of a combination iron and gold farm I built in one of my worlds.
It has 6 villages separated by 66 blocks horizontally (the minimum needed to prevent merging) and 70 blocks vertically, with a Redstone Jazz pigman spawner in the middle. It's not a monster iron producer like Tango Tek's Iron Titan, but it gives me more iron than I need in SSP, and would probably be enough for a small server (I also get a little gold and rotten flesh as a bonus).
Of course, for trading my design above sucks, because the villager pods are inaccessible. When I made the underground iron farm in my more recent world I remedied that by making the villager pod wrap all the way around the golem trap area (like yours does). I also made it tilled farmland with a carrot crop and made sure one of my starter villagers was a brown-coat farmer class (farmer, fisherman, fletcher, shepherd) so that I only needed 2 villagers to start, and I could let them breed unattended until I had enough for golems.
In theory I could increase the number of doors in this farm to 80 while still only using 4 sky access blocks, and that would give me twice as many villagers to trade with (28 vs 14), but I was really only looking for Mending, which the guy right next to the entrance door has, so I'm happy.
It's not related to the average position of the villagers, it's the geometric center of all the valid houses, it's just that a door needs a villager to be a house. You could put 32 of your 35 villagers in one corner, and 1 each in the other 3 corners, and the average position of your villagers would be heavily skewed toward the 31 villagers, but the village would be properly centered on your golem trap. It only takes 1 villager to validate all the doors within 16 blocks (note that they can also detect doors up to 3 blocks above and 5 blocks below).
With 184 doors you should have 64 villagers (provided they are all validated as houses), so as long as they get fed, or you keep trading with them they should keep breeding up to 64. Farmer class villagers include the Shepherd, Fisherman and Fletcher as well as the Farmer. Any of those will farm crops and feed other villagers for unattended breeding (of course you actually need crops, which I didn't see in your pictures).
If you actually need a "Farmer" villager, then you just need to keep those villagers frisky by feeding or trading with them (or plant some crops and let the other brown coats do the feeding).
One other thing, the vertical center of the "village" is defined by the blocks the doors are placed on. Since we don't have a "door" emoji/icon on this forum, I'll use red blocks for door blocks (top/bottom)
If all of your doors are on the same level, then the gap between the cobblestone and the red block above it would represent the vertical center of the village, and golems can spawn +/- 3 blocks from that. So for two spawn floors you would place them like this.
From what I can see in your pictures it looks like you only have a single spawn floor. Adding a second one should get you a little more iron, since you would have fewer missed spawn attempts.
Unfortunately it's not that simple. Villager breeding is random. The type of baby villager born has nothing to do with the parents. Any pair of villagers can have any type of baby villager.
Another option beside continuing to breed villagers in your iron farm would be to build an infinite villager breeder. Infinite breeders are the best way to get exactly the villager you want, say a librarian with mending for 10 emeralds, but you will also need a lot of automated farms to generate the goods you'll need for trading with the villagers.
Not really. They're pretty stubborn and it's hard to make them do what you want them to. If you really want to control their movements, you can put them into minecarts. Otherwise, the best you can do is keep them out of places you don't want them to be; you can't really force them to go to any one particular place. Due to the way their positions are calculated, they do tend to prefer the northwesterly direction and, over time, will tend to congregate towards that side of the village if they are able to wander freely, but this is not very precise or reliable.
Village Mechanics: A not-so-brief guide - Update 2017! Now with 1.8 breeding mechanics! Long-overdue trading info, coming soon!
You think magic isn't real? Consider this: for every person, there is a sentence -- a series of words -- which has the power to destroy them.
No, you can toss in food to the villagers in general and they will share with each other and breed. But a given number of doors has a hard ceiling on how many villagers can be bred in that village before they simply stop emitting hearts and making babies. So if you've got a bunch of un-wanted villagers or villagers with unsatisfactory trade prices, get rid of them. Move them out to a distant holding area (more than 64 blocks away from the village edge) if you want to save them for use in a non-trading village for iron production only, for example. Or simply toss them into your iron golem kill mechanism, through a portal into the nether, or some other place outside the village where they can be killed without hurting your village reputation. Keep a few well-fed villagers inside your village and they'll breed up replacements for the missing villagers.
This might help here. Make sure to read every page. Msg me if it helped you.;)
https://en.oxforddictionaries.com/