Interface for setting the position of an emitter.
```cs
// Base interface
public interface IPosition
{
Vector3F GetPosition();
}
// Implementations
public struct Vector3F : IPosition
{
public Vector3F GetPosition() => this;
}
public class FuncPosition : IPosition
{
public FuncPosition(Func<Vector3F> position)
{
this.position = position;
}
Func<Vector3F> position;
public Vector3F GetPosition() => position();
}
```