Launch Options¶

Example¶

var launchOption = new MLaunchOption 
{
    Session = MSession.CreateOfflineSession("gamer123"),
    Features = new string[] { "feature_name" },

    JavaPath = "javaw.exe",
    MaximumRamMb = 4096,
    MinimumRamMb = 1024,
    DockName = "Minecraft",
    DockIcon = "/path/icon.icns",

    IsDemo = false,
    ScreenWidth = 1600,
    ScreenHeight = 900,
    FullScreen = false,
    QuickPlayPath = "/path/quickplay",
    QuickPlaySingleplayer = "world name",
    QuickPlayRealms = "realm id",
    ServerIp = "mc.hypixel.net",
    ServerPort = 25565,

    ClientId = "clientid",
    VersionType = "CmlLib",
    GameLauncherName = "CmlLib",
    GameLauncherVersion = "2",
    UserProperties = "{}",

    ArgumentDictionary = new Dictionary<string, string>
    {
        { "key", "value" },
        { "auth_xuid", "12345678" }
    },
    JvmArgumentOverrides = new MArgument[]
    {
        new MArgument("--key=value")
    },
    ExtraJvmArguments = new MArgument[]
    {
        new MArgument("--key=value"),
        MArgument.FromCommandLine("-Dminecraft.api.env=custom -Dminecraft.api.auth.host=https://invalid.invalid -Dminecraft.api.account.host=https://invalid.invalid -Dminecraft.api.session.host=https://invalid.invalid -Dminecraft.api.services.host=https://invalid.invalid"),
    },
    ExtraGameArguments = new MArgument[]
    {
        new MArgument("--key=value"),
        new MArgument(["--key1", "--key2", "value2"]),
    }
};

Session¶

Type: MSession

See Login and Session for how to log in Minecraft and get game session.

Game session (Username, UUID, AccessToken, etc...). If the value is null, the default session with username tester123 is used.

Features¶

Type: IEnumerable<string>

Enable features.

JavaPath¶

Type: string

Java binary path. If the value is null, ArgumentNullException is thrown.

MaximumRamMb¶

Type: int

-Xmx JVM parameter. It is used to set the maximum heap size of Minecraft. If the value is a negative value, ArgumentOutOfRangeException is thrown. The default value is 2048 (2GB) for X64, 1024 (1GB) for other platforms. Note: You can't set this property to any number higher than 1024 when using 32bit Java.

MinimumRamMb¶

Type: int

-Xms JVM parameter. It is used to set the minimum heap size of Minecraft. If the value is a negative value or greater than MaximumRamMb, ArgumentOutOfRangeException is thrown.

DockName¶

Type: string

macOS dock name of Minecraft. In some macOS versions, you must set this option. Known Issues

DockIcon¶

Type: string

macOS dock icon of minecraft. It should be an absolute file path to an image that has the dimensions 256x256 and is of the icns format.

IsDemo¶

Type: bool

Enable is_demo_user feature and launch a game in demo version.

ScreenWidth / ScreenHeight¶

Type: int

Initial window size of Minecraft. It works if the value of the two options is greater than 0. If the value of both options is 0, let the game decide the window size. If one of these options is negative, ArgumentOutOfRangeException will be thrown. Not all versions of Minecraft support this option.

FullScreen¶

Type: bool

Launch Minecraft as full screen. Not all versions of Minecraft support this option.

QuickPlayPath¶

Type: string

Set QuickPlayPath argument. QuickPlay

QuickPlaySingleplayer¶

Type: string

Set QuickPlaySingleplayer argument. QuickPlay

QuickPlayRealms¶

Type: string

Set QuickPlayRealms argument. QuickPlay

ServerIp / ServerPort¶

Type: string / int

Connecting to a server directly when Minecraft is loading is done. The default value of ServerPort is 25565. If ServerPort is not a valid port number (0-65535), ArgumentOutOfRangeException is thrown. If the starting version supports QuickPlay, the launcher will enable QuickPlayMultiplayer feature, otherwise the launcher will append --serverIp and --serverPort arguments.

note1: Not all versions of Minecraft support this option.

note2: If you set a domain with an SRV record, the connection may fail. Set the actual address and port that the SRV record points to directly.

ClientId¶

Type: string

${clientid}

VersionType¶

Type: string

${version_type}. If the value is null, the Type property of the starting version is used. VersionType is displayed in the lower left corner of the main screen. Not all versions of Minecraft support this.

GameLauncherName¶

Type: string

${launcher_name}. The default value is minecraft-launcher , which is the same as the Mojang launcher.

GameLauncherVersion¶

Type: string

${launcher_version}. The default value is 2, which is the same as the Mojang launcher.

UserProperties¶

Type: string

${user_properties}. for Twitch livestreaming

ArgumentDictionary¶

Type: IReadOnlyDictionary<string, string>

When building an argument in the launcher, ${variable_name} will be replaced with the appropriate value. This option specifies variable_name as the key and the string to be replaced as the value.

JVMArgumentOverrides¶

Type: IEnumerable<MArgument>

Override all JVM arguments. When this option is not null, ExtraJVMArguments and JVMArguments are ignored.

See MArgument

ExtraJVMArguments¶

Type: IEnumerable<MArgument>

Set extra JVM arguments. See MArgument

Default arguments are:

-XX:+UnlockExperimentalVMOptions
-XX:+UseG1GC
-XX:G1NewSizePercent=20
-XX:G1ReservePercent=20
-XX:MaxGCPauseMillis=50
-XX:G1HeapRegionSize=16M

ExtraGameArguments¶

Type: IEnumerable<MArgument>

Set extra game arguments. See MArgument