private void SpawnAsteroid()
    {
        AsteroidOld newAst = (AsteroidOld)asteroid_.Instance();

        InitializeAsteroid(newAst);
        AddChild(newAst);
    }
    private void InitializeAsteroid(AsteroidOld asteroid)
    {
        var rect = GetViewport().Size;

        asteroid.Position = new Vector2((float)GD.RandRange(0, rect.x), -100);

        asteroid.AngularVelocity = (float)GD.RandRange(-4, 4);
        asteroid.AngularDamp     = 0;
        asteroid.LinearVelocity  = new Vector2((float)GD.RandRange(-300, 300), 300);
        asteroid.LinearDamp      = 0;
    }