GameSettings

This is the full list of what the API gives you, one section for each part. Text in brackets at the end of a note is extra detail you can skip on a first read.

GameSettings reads the options the player chose in the game’s Options screen. Each read gives a snapshot of what is saved when you ask.

GameSettings reads the player's options

This is the class to start from. Display() and Quality() give you the saved options, SetFov and ClearFov change the field of view, and Changed tells you when the game applies new display or quality options.

public static class GameSettings
{
    public static event Action Changed;
    public static bool IsAvailable { get; }
    public static GameDisplay Display();
    public static GameQuality Quality();
    public static int MouseSensitivity();
    public static bool InvertX();
    public static bool InvertY();
    public static bool HintsEnabled();
    public static bool ToggleSprint();
    public static bool ToggleCrouch();
    public static bool SetFov(int fov);
    public static bool SetFov(string owner, int fov);
    public static bool ClearFov(string owner);
}

Method	Returns	What it does
`Display()`	`GameDisplay`	The display options. `null` when they are not available yet.
`Quality()`	`GameQuality`	The graphics quality options. `null` when they are not available yet.
`MouseSensitivity()`	`int`	The saved mouse sensitivity value.
`InvertX()`	`bool`	`true` when the mouse is inverted left to right.
`InvertY()`	`bool`	`true` when the mouse is inverted up and down.
`HintsEnabled()`	`bool`	`true` when the card game’s hints are switched on.
`ToggleSprint()`	`bool`	`true` for toggle mode, `false` for hold mode.
`ToggleCrouch()`	`bool`	`true` for toggle mode, `false` for hold mode.
`SetFov(fov)`	`bool`	Overwrites the player’s saved field of view.
`SetFov(owner, fov)`	`bool`	Sets the field of view in memory only.
`ClearFov(owner)`	`bool`	Gives the field of view back.

Property	Type	What it means
`IsAvailable`	`bool`	`true` when the `Changed` event works. See Details.

Event	Gives you	When it fires
`Changed`	Nothing	The game has applied new display or quality options.

GameScreenMode window, borderless or full screen

GameDisplay.ScreenMode gives you one of these.

public enum GameScreenMode
{
    Windowed = 0,
    Borderless = 1,
    FullScreen = 2
}

Value	Meaning
`Windowed`	A normal window.
`Borderless`	A window with no border that fills the screen.
`FullScreen`	Full screen.

GameDisplay the saved display options

GameSettings.Display() gives you one of these, or null when the game has not created its options yet. It is a snapshot of what is saved when you ask. (It is built from the game’s saved display settings.)

public sealed class GameDisplay
{
    public int Width { get; }
    public int Height { get; }
    public int RefreshRate { get; }
    public GameScreenMode ScreenMode { get; }
    public bool VSync { get; }
    public int Fov { get; }
    public int Brightness { get; }
    public bool RunInBackground { get; }
}

Property	Type	What it means
`Width`	`int`	The screen width in pixels. `0` until the game has saved it once.
`Height`	`int`	The screen height in pixels. `0` until the game has saved it once.
`RefreshRate`	`int`	The refresh rate in hertz. `0` until the game has saved it once.
`ScreenMode`	`GameScreenMode`	Window, borderless or full screen.
`VSync`	`bool`	`true` when vertical sync is on.
`Fov`	`int`	The field of view the player saved, in degrees.
`Brightness`	`int`	The brightness slider value. The game’s default is 100.
`RunInBackground`	`bool`	`true` when the game keeps running while its window is not in front.

GameQuality the saved graphics options

GameSettings.Quality() gives you one of these, or null when the game has not created its options yet. Its numbers are the game’s own index numbers, not named levels. (It is built from the game’s saved quality settings.)

public sealed class GameQuality
{
    public int Level { get; }
    public bool Custom { get; }
    public int ShadowQuality { get; }
    public int ShadowResolution { get; }
    public int TextureResolution { get; }
    public int Ssao { get; }
    public int Antialiasing { get; }
    public int PostFx { get; }
}

Property	Type	What it means
`Level`	`int`	The number of the quality preset the player picked.
`Custom`	`bool`	`true` when the player picked the Custom preset.
`ShadowQuality`	`int`	The game’s index for shadow quality.
`ShadowResolution`	`int`	The game’s index for shadow resolution.
`TextureResolution`	`int`	The game’s index for texture resolution.
`Ssao`	`int`	The game’s index for ambient shading (SSAO).
`Antialiasing`	`int`	The game’s index for edge smoothing.
`PostFx`	`int`	The game’s index for screen effects.

Display and quality

Display() gives the display options the game last saved, or null when the game has not created them yet. (it reads DisplaySave.instance.displaySave; Width, Height and RefreshRate are 0 until the game has saved them once)
ScreenMode turns the game’s saved text into one of three values. The text Full Screen becomes FullScreen, Borderless becomes Borderless, and anything else becomes Windowed.
Brightness is the slider value, and the game applies it as that number divided by 100. The framework does not check that it is in a range.
RunInBackground is the saved Run In Background option. It is false by default.
Brightness and RunInBackground come from Display(), so they exist only when Display() does.
Quality() gives the graphics options. The numbers are the game’s own index numbers, not named levels. It gives null when the game has not created them yet.
Level is the preset the player picked, and Custom is true for the Custom preset.
MouseSensitivity() is the raw saved value. It is 900 by default, and it is not a multiplier. The game’s camera uses this number divided by 100 with whole-number division, so 900 gives 9, and anything below 100 gives 0. (the division is in SetControls.SetSensitivity)
InvertX() and InvertY() are true when the saved mouse inversion includes that direction. (the saved modes are X, Y, X + Y, and an empty text for none)
ToggleSprint() and ToggleCrouch() give true for toggle mode and false for hold mode. In toggle mode you press once to start and press again to stop. In hold mode the action lasts while you hold the key. (the game checks !toggleSprint and !toggleCrouch for hold mode in OpenSewerCharacterController)
Read false as hold, which is the opposite of what the name may make you think.
If the game has no controls save yet, or the read fails, both give true, which is the game’s default. This is the one read that does not give false when nothing is there.
HintsEnabled() tells you whether the card game’s hints are switched on. The hints are the rules box that the card game shows. The player turns them on and off with the Hints key, which is K by default. It is true by default. (it reads HintOverlay.HintsEnabled, a PlayerPrefs value (HintOverlayEnabled, default 1))
The game has no hints option in its Options screen, so there is nothing to find there. (the game’s own HintOverlay.HintsToggled event exists, but the framework does not offer it, so subscribe to it directly if you need it)
Changed fires after the player applies display or quality options. The game also applies the quality options once when the Options screen opens, so Changed can fire when that screen opens. Compare the values before you act on it.
Changed does not fire for every option. It does not fire when the player changes only the field of view, the mouse sensitivity, the mouse inversion, the brightness, the run in background option, sprint or crouch mode, or the hints. Read those when you need them. (it fires after OptionsMenu.applyDisplaySettings() and OptionsMenu.applyQualitySettings(); SetBrightness, SetRunInBackground, SetToggleSprint and SetToggleCrouch on OptionsMenu do not call either one)

Field of view

SetFov(fov) overwrites the player’s own field of view setting, and it writes the setting to Display.json on disk at once. Do not use it for a zoom or a short change.
The player’s chosen value is lost, and it stays lost after a restart. A second mod that calls it simply replaces the first.
Use SetFov(owner, fov) or ScreenFx.SetFovOverride(owner, fov) instead, which never touch the file.
SetFov(fov) gives true when it saved the value. It gives false for a value outside 30 to 120, when the game has no display save yet, and while a save is loading or being written.
The options screen reads the saved value when it opens, so a screen that is already open keeps its old slider position.
The camera follows on the next frame, unless a field of view override is set. Then the camera stays where the override put it. The call does not raise Changed. (it calls the game’s own DisplaySave.SaveDisplay("Fov", ...), the same call the options slider makes, and the camera follows through SetCameraFOV.Update; the range 30 to 120 is the ScreenFx limit, which is not necessarily the range of the game’s slider)
SetFov(owner, fov) sets the field of view in memory only, and ClearFov(owner) takes it back.
The newest owner wins, clearing falls back to the owner set before it, and a scene load that replaces the whole scene clears all of them.
The player’s saved setting is never written. It is the same as ScreenFx.SetFovOverride(owner, fov) and ScreenFx.ClearFovOverride(owner). See Screen effects. An owner is your mod’s id (see the glossary).
SetFov(owner, fov) gives false for a value outside 30 to 120, or when the screen effects are not available. An owner that is not a valid mod id throws an ArgumentException. (it returns false when ScreenFx.IsAvailable is false)

Limits

You can’t read or change a subtitles option. The game’s Options screen has no subtitle setting.
You can’t read the display number. The game saves which display it uses, but this API does not give it to you yet.
You can’t change any other option. The size, refresh rate, screen mode, vertical sync, quality, mouse, inversion and hints are changed by the Options screen and its apply methods. A change from here would skip those, so it is not offered.
The field of view has its own save call, so it is the only option you can change. (the apply methods are applyDisplaySettings and applyQualitySettings on OptionsMenu)