Intro To Entities

PlaceholderMod allows the creation of Entities through C# Scripting. To define an Entity, you need to inherit from BaseEntity and override OnStart() and OnUpdate() methods for all logic.

public class MyEntity : BaseEntity
{
    // This will run once on Start
    public override void Start()
    {
        Console.WriteLine("Starting MyEntity...");
    }

    // This will run once per frame
    public override void Update()
    {
        Console.WriteLine("Updating MyEntity!");
    }
}

Exposing Entity Variables to the Editor

To expose an Entity Variable to the Editor, you can utilize the [EntityProperty] Attribute. Any Variables marked with this Attribute will be accessible and editable directly from the Editor.

[EntityProperty("light_color")]
public Vector4 Color = new Vector4(255.0f, 255.0f, 255.0f, 200.0f);

Entity Deletion

Entities can be deleted through the Entity.DestroyDeferred() method. This method will clean up the Entities with their OnDestroy() method before deleting it from the world.

// Run any Entity clean-up and then remove it from the World
EntityReference.DestroyDeferred();

Entity Types

Entities come in 2 primary types, Point Entities and Brush Entities.

Point Entity

A Point Entity is an Entity that occupies a single point in the world.

public class PropEntity : MeshEntity
{
    /// <summary>
    /// Create Mesh from this path.
    /// </summary>
    [EntityProperty("model")]
    public string MeshPath;

    /// <summary>
    /// Get Material from this path.
    /// </summary>
    [EntityProperty("skin")]
    public string MaterialPath;

    public override void Start()
    {
        Material material = FileSystem.GetMaterial(MaterialPath);
        Mesh = new Mesh(FileSystem.GetModelPath(MeshPath), material);

        GameWindow.CurrentWindow.Renderer.InitMesh(Mesh); // Render the (empty) mesh
    }
}

Brush Entity

A Brush Entity is an Entity that occupies Map Geometry (Brushes).