Expand description

EU4 Save is a library to ergonomically work with EU4 saves (ironman + mp).

use eu4save::{Eu4File, Encoding, CountryTag, EnvTokens};

let data = std::fs::read("assets/saves/eng.txt.compressed.eu4")?;
let file = Eu4File::from_slice(&data)?;
let save = file.deserializer().build_save(&EnvTokens)?;
assert_eq!(file.encoding(), Encoding::TextZip);
assert_eq!(save.meta.player, "ENG".parse()?);

Querying

Even once decoded, the data might be too low level. For example a country can have an income ledger that looks like:

income = { 1.000 0 2.000 0.000 1.500 }

While the structure will decoded successfully into a vector, the context of what each index means is missing. What value represents the income from trade?

To help solve questions like these, the Query API was created

use eu4save::{Eu4File, Encoding, CountryTag, EnvTokens, query::Query};
use std::io::Cursor;

let data = std::fs::read("assets/saves/eng.txt.compressed.eu4")?;
let file = Eu4File::from_slice(&data)?;
let save = file.deserializer().build_save(&EnvTokens)?;
let save_query = Query::from_save(save);
let trade = save_query.country(&"ENG".parse()?)
    .map(|country| save_query.country_income_breakdown(country))
    .map(|income| income.trade);
assert_eq!(Some(17.982), trade);

Ironman

By default, ironman saves will not be decoded properly.

To enable support, one must supply an environment variable (EU4_IRONMAN_TOKENS) that points to a newline delimited text file of token descriptions. For instance:

0xffff my_test_token
0xeeee my_test_token2

PDS has declared that in order to comply with EU4’s terms of use, the list of tokens must not be shared. I am also restricted from divulging how the list of tokens can be derived.

You may look to other projects EU4 ironman projects like ironmelt or paperman for inspiration.

Modules

Parsing and deserializing EU4 save files
Repository of raw structs extracted from a save file
Ergonomic module for querying info from a save file

Structs

Wrapper around a Country’s unique three byte tag
Builtin token resolver based on EU4_IRONMAN_TOKENS
Struct specialized to parsing, formatting, and manipulating dates in EU4 A date without a time component
An EU4 Error
Entrypoint for parsing EU4 saves
Convert a binary save to plaintext
Output from melting a binary save to plaintext
An province numerical identifier
A tag value and where it is stored in the save
Tracks tag progression throughput history
Resolves tag up until a certain point in time

Enums

Describes the format of the save before decoding
Specific type of error
Customize how the deserializer reacts when a token can’t be resolved

Traits

Common set of methods between all the date components

Functions

Map dlc name to its id
EU4’s start date