Achievement

Achievement reads the game’s achievements and lets your mod unlock them or move their progress. An unlock counts for the real Steam achievement too, so it cannot be taken back from a mod.

Achievement the game's achievements

This is the class you start from. All() and Get read the achievements, Trigger unlocks one, AddProgress and SetProgress move its progress, and ItemLinks() lists the items that trigger them.

public static class Achievement
{
    public static List<AchievementInfo> All();
    public static AchievementInfo Get(string id);
    public static bool IsUnlocked(string id);
    public static bool Trigger(string id);
    public static bool AddProgress(string id, float amount);
    public static bool SetProgress(string id, float value);
    public static List<AchievementItemLink> ItemLinks();
}

Method	Returns	What it does
`All()`	`List<AchievementInfo>`	Every achievement. It is empty until the game has loaded them.
`Get(id)`	`AchievementInfo`	One achievement. `null` when the id is not known.
`IsUnlocked(id)`	`bool`	`true` when it is unlocked. `false` for an id the game does not know.
`Trigger(id)`	`bool`	Asks the game to unlock it. `true` when it is unlocked afterwards.
`AddProgress(id, amount)`	`bool`	Adds to its progress. `true` when the game was told.
`SetProgress(id, value)`	`bool`	Sets its progress. `true` when the game was told.
`ItemLinks()`	`List<AchievementItemLink>`	Which items trigger which achievements.

AchievementInfo one achievement

All() and Get(id) give you this, one per achievement, read from the game’s own achievements.

public sealed class AchievementInfo
{
    public string Id { get; }
    public float Progress { get; }
    public float MaxProgress { get; }
    public bool Unlocked { get; }
    public bool Enabled { get; }
}

Property	Type	What it means
`Id`	`string`	The achievement’s id.
`Progress`	`float`	How far along it is.
`MaxProgress`	`float`	The progress it needs to unlock.
`Unlocked`	`bool`	`true` when it has been unlocked.
`Enabled`	`bool`	`true` when the achievement is switched on in the game.

AchievementItemLink an item that triggers an achievement

ItemLinks() gives you one of these for each item that triggers an achievement. OnConsumed says whether the achievement fires when the item is used up or when it is picked up.

public sealed class AchievementItemLink
{
    public int ItemId { get; }
    public string AchievementId { get; }
    public bool OnConsumed { get; }
}

Property	Type	What it means
`ItemId`	`int`	The item’s id.
`AchievementId`	`string`	The achievement it triggers.
`OnConsumed`	`bool`	`true` when it fires when the item is consumed, `false` when the item is collected.

Things to know

All and Get read the game’s achievements, and you can’t change them directly. Unlocked is the game’s own flag.
Trigger only unlocks an achievement when its progress is full. An achievement with no progress counts as full, so it unlocks at once. When it unlocks, the game also gives its rewards. (It calls the game’s TriggerAchievement(id).)
AddProgress and SetProgress move the progress, and the game updates the Steam stat. The achievement unlocks once the progress is full. (Both call TriggerAchievement(id, progress, set).)
AddProgress and SetProgress give back true when the call was passed to the game. A number that is NaN, infinite or below zero is refused with false before the game is called, so a bad number cannot get into your save or the Steam stat.
ItemLinks() lists the links for the scene the player is in. (It reads the item achievement list of the current scene.)
The class is called Achievement, not Achievements, so it does not clash with the game’s own Achievements class. Inside the framework’s own code Achievements must keep meaning the game class.

Limits

Trigger, AddProgress and SetProgress do nothing and give back false for an id the game does not know, an achievement that is turned off, a game that has not loaded its achievements yet, or while the developer console is open. (The console case is the game’s globalDisable.)