Mod Creation_C# Programming_Mod Compatibility: Soft Dependency

Mod Compatibility: Soft Dependency

BepInDependency Attribute

Add the attribute on top of your BaseUnityPlugin class.

Use BepInDependency.DependencyFlags.SoftDependency for the 2nd argument.

For example, we will try to access the API of OtherMod.

[BepInDependency("com.chen.othermod", BepInDependency.DependencyFlags.SoftDependency)]
public class MyPlugin : BaseUnityPlugin
{

}

Make a non nested wrapper class

This is optional but much cleaner just for the sake of project organization.

Adding a soft dependency from a mod does not end there.

The wrapper class will house all the API from the mod that we are soft-dependending on.

public static class OtherModCompatibility
{

}

MethodImpl

The important part is that any methods that require any stuff coming from the soft dependency assembly we are interested in only used behind methods that have these two attributes.

[MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.NoOptimization)]

This is due to internal details on how the c# runtime works.

If these are not here you'll most likely get Exceptions thrown at you telling you the soft dependency is not loaded.

public static class OtherModCompatibility
{
    private static bool? _enabled;

    public static bool enabled {
        get {
            if (_enabled == null) {
                _enabled = BepInEx.Bootstrap.Chainloader.PluginInfos.ContainsKey("com.chen.othermod");
            }
            return (bool)_enabled;
        }
    }

    [MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.NoOptimization)]
    public static void SomeMethodThatRequireTheDependencyToBeHere()
    {
      // stuff that require the dependency to be loaded
    }
}

Finally, some example usage.

[BepInDependency("com.chen.othermod", BepInDependency.DependencyFlags.SoftDependency)]
public class MyPlugin : BaseUnityPlugin
{
    private void Awake()
    {
        if (OtherModCompatibility.enabled)
        {
            OtherModCompatibility.SomeMethodThatRequireTheDependencyToBeHere();
        }
    }
}