PenPosts

Breeding caps per pen instead of per radius: write "Pen" on a sign, and the animals inside its fence only count each other.

In the base game, a tamed animal stops breeding ("too crowded") when too many of its kind are within a radius around it, wherever they are: in the next pen, behind the barn wall, even wild ones. With PenPosts, a sign marks a pen, and animals inside it only count the animals in that same pen.

Features

Pens follow the fence. The pen is the area inside the fence, walls or rock around the sign. Gates count as shut, even when open.
Caps per pen or per kind. One cap for the whole pen, or one for each kind of animal, written on the sign.
Young count, eggs don't. Chicks and asksvin hatchlings count towards the cap like piglets, cubs and calves; eggs lying in the pen do not.
See the pen. A pen sign shows the pen's area, cap and animals, and marks its edge on the ground.
Animals stay in. A tame animal that gets out of a fenced pen (an open gate, a slip through a wall or rock) is put back where it last stood inside; one that sinks into the floor is lifted back up, and young are born on their mother's side of the fence or cave wall (one born outside anyway is put in). Animals that follow someone or carry a rider are free to go. One put back more than 4 times in 2 minutes is left alone for 10 minutes, and the log says where it is.
Flying animals on a leash. A tame drake can fly up to 10 m past the edge of any pen, then turns back. Only one that ends up 40 m beyond that, and is not fighting, is brought back.
Falling animals are caught. A tame animal that falls through the ground or a floor, in a pen or not, is put back where it last stood.
No food wasted. Tamed animals only eat when it does them some good: when they can still breed, when a herd bell can still collect from them, or when they wear a saddle or riding handle (food refills a mount's stamina). Animals in a full pen, crowded animals outside pens, growing young and tame kinds that never breed leave food alone until that changes. Wild animals being tamed eat as usual.
One-hit Butcher knife. The game's knife does 1000 damage, too little for big or starred animals (a 2-star lox has 3000 health). PenPosts raises it to 100000; it still only hurts tamed animals.

Finding a mate works as before, and animals outside every pen breed as before.

How to use

Fence in the animals.
Put a sign inside the pen, or on its fence, and write Pen 10 Boar 8.
Look at the sign. Green marks on the ground mean the fence closes the pen; the hover text lists the cap and the animals inside.

In Pen 10 Boar 8, Pen makes the sign a pen. 10 is the radius in metres, used only when no closed fence is found; it can be left out. Boar 8: boars in this pen stop breeding at 8.

Sign text	What it does
`Pen`	Every animal uses its own breeding cap
`Pen 10 Boar 8 Lox 4`	A cap for each kind named
`Pen 10 cap 8`	A cap of 8 for every kind (`max 8` or `Pen 10 8` work too)
`Pen 10 Boars`	A word without a number is the pen's name
`Pen 10 round`	Always a circle with a 10 m radius (`circle` works too)
`Pen 10 square`	Always a 20 m square, turned the way the sign faces (`box` works too)

Animal names work in the singular or plural (boar, boars, wolves). A kind the sign does not name uses the sign's cap for every kind if it has one, else the Pen cap setting, else its own cap. PenPosts adds no keys; E still edits the sign.

How the pen is found

The pen is traced out from the sign the way an animal walks, stopping at fences, walls, rocks and steps too high to climb. Gaps narrower than about 0.75 m are ignored. A sign on a fence between two pens belongs to the side with more tamed animals.
A wider gap, or a fence around more than 3000 m², makes the pen a circle around the sign (or a square, with Fallback shape). The hover text says why ("1.2 m gap 6 m north-east of the sign").
The pen is measured again soon after nearby building changes, and every few minutes. An animal inside several pens belongs to the nearest sign.
In a cave dug with Hearth Below, the pen is measured on the cave's floor and its rock walls count as a fence. A round or square pen in a cave only counts the animals in that cave.
Round and square pens have no fence, so they do not hold animals in.

Pen marks

Look at a pen sign for a moment and the pen appears: marks along its fence or square, or a ring and a see-through dome for a round pen. The marks are twice a ward's size, sit on top of rocks and logs at the edge, stay 20 seconds after you look away, and change as soon as the pen does.

Green: the pen is fine (a closed fence, or the shape the sign asks for).
Grey-blue: the fence could not be used, so the pen is the fallback circle or square for now.
Orange ring: the opening that keeps the fence from closing. Yellow ring: a gap small enough to ignore.

Configuration

Settings are in BepInEx/config/anwo.PenPosts.cfg and can be changed in game with a configuration manager.

1 - Pens

Setting	Default	Scope	Description
Smart area	`true`	All players	The pen is the area inside its fence or cave walls. Off: always the Fallback shape. Same on every PC
Max area	`3000`	All players	Largest fenced pen in m² (25-10000); bigger uses the Fallback shape. Same on every PC
Fallback shape	`Round`	All players	Shape of a pen without a closed fence: `Round` or `Square`. Same on every PC
Default radius	`10`	All players	Radius in metres when the sign gives none; half the side of a square (2-60). Same on every PC
Max radius	`40`	All players	Largest radius a sign may set, and how far a fence is looked for, in metres (5-100). Same on every PC
Pen cap	`0`	All players	Cap for pens whose sign sets none (0-200). 0: each animal's own (LetMeTameYou's or the game's). Same on every PC
Count young, not eggs	`true`	All players	In a pen, young from eggs count and eggs don't. Off: as in the game. Same on every PC
No food when full	`true`	All players	Tamed animals in a full pen leave food alone, unless a herd bell can collect from them or they are saddled. Same on every PC
Also outside pens	`true`	All players	With No food when full: crowded animals outside pens, young and non-breeding kinds leave food alone too. Same on every PC
Keep animals in	`true`	All players	Tame animals that get out of a fenced pen or sink into its floor are put back. Same on every PC
Catch falling animals	`true`	All players	Tame animals that fall through the ground or a floor are put back. Same on every PC
Born on the mother's side	`true`	All players	Young and eggs come out on the mother's side of walls, fences and cave rock, inside her pen. Same on every PC
Flying leash	`10`	All players	Metres past a pen's edge a tame flying animal may fly (0-100). 0: no leash. Needs Keep animals in. Same on every PC

2 - Display

Setting	Default	Scope	Description
Show pen info on sign	`true`	Client	Adds the pen's area, cap and animals to the sign's hover text
Show pen area	`true`	Client	Shows the pen's edge while you look at a pen sign
Show pen area for	`20`	Client	Seconds the edge stays after you look away (3-300)
Pen mark size	`2`	Client	Size of the marks, as times a ward's (0.5-5)

3 - Butcher knife

Setting	Default	Scope	Description
Butcher knife damage	`100000`	Client	Damage of your own Butcher knife hits (0-1000000). 0: the game's own (1000)

Multiplayer

Every player needs PenPosts. Breeding, feeding and keeping animals in are handled by whichever player's game runs the animals at the time, so mixed installs give mixed results.
Use the same 1 - Pens settings on every PC. The host's settings are not sent to other players. Display and Butcher knife are each player's own.
There is no version check: a player without the mod can join, and the animals their game runs follow the game's own rules.

Compatibility

Works with the game's breeding and any mod that uses it.
LetMeTameYou (optional): its "Too Crowded / Ready to Procreate" hover text counts the pen too, and its caps apply when neither the sign nor Pen cap sets one.
Herd Bell: animals a bell can still collect from keep eating in a full pen.
Hearth Below: pens work in dug caves, and animals there are never lifted out.
Feeding troughs from other mods (such as Valharvest's) work as usual; animals in a full pen leave them alone.
Other mods' sign keys, such as Q from Zen mods, keep working.
If another mod makes the Butcher knife hurt more than tamed animals, its damage is left alone.
Patches: the breeding count (Procreation.Procreate, SpawnSystem.GetNrOfInstances), tame animals' hunger, the sign's hover text.

Uninstalling

Nothing is saved to the world. Without the mod, a pen sign is just a sign and the Butcher knife does its usual damage.

About

Made with Claude (Anthropic's AI model) and tagged AI Generated, as Thunderstore's rules ask. Built for Valheim 1.0.17 (Deep North; also 1.0.16) with BepInEx 5.4.2351.