# C#: Loops and delays

Source: https://tweens.gd/csharp/loops/

Ping-pong sends a motion back to where it started; repeats play it again. Together they make idle motion that runs on its own.

Examples use `using Godot;` and `using tweens.gd;` in a Node method, with targets inside the scene tree.

## Loop forever

Godot's Tween

```csharp
var tween = sprite.CreateTween().SetLoops()
    .SetTrans(Tween.TransitionType.Sine).SetEase(Tween.EaseType.InOut);
tween.TweenProperty(sprite, "scale", new Vector2(1.1f, 1.1f), 0.8);
tween.TweenProperty(sprite, "scale", Vector2.One, 0.8);
```

tweens.gd

```csharp
var pulse = new Tweens.Scale2D(1.1, 0.8, InOut.Sine)
{
    PingPong = true,
    Repeats = TweenOptions.Infinite,
};

sprite.Tween(pulse);
```

The sprite grows for 0.8 seconds, shrinks for 0.8 seconds, and repeats until cancelled or removed from the tree. Ping-pong returns to the scale the sprite had at the start, so the return leg needs no value of its own.

## Count cycles

| Set | Effect |
| --- | --- |
| `Repeats = 2` | Three cycles: the first plus two repeats |
| `PingPong = true` | Each cycle goes there and back; `Duration` applies to each leg |
| `PingPongInterval` | Pause at the far end before the return leg |
| `RepeatInterval` | Pause between cycles |

**Try it:** raise `Repeats`, then drag the timeline to see where each interval falls.

Interactive preview: https://tweens.gd/csharp/loops/

## Hold during a delay

`Fill` chooses what a delayed tween shows before it starts and after it ends. For an entrance, `FillMode.Both` applies `From` during the delay and keeps the final value:

```csharp
var fadeIn = new Tweens.ModulateAlpha
{
    From = 0,
    Duration = 0.3,
    Delay = 0.5,
    Fill = FillMode.Both,
};

label.Tween(fadeIn);
```

The label stays hidden for half a second, then fades in to its own alpha. The default fill, `RetainFinalValue`, would leave it visible during the delay, so it would blink out before fading in.

Each row below plays one delayed tween with a different fill mode:

Initial delayPlayingNatural completion

`RetainFinalValue`

`ApplyFromDuringDelay`

`Both`

`None`

**From** at left**captured initial value** (dashed)**To** at right

Cancelling keeps the current value

Fill modes restore the initial value only on natural completion. A cancelled tween keeps its latest value.

[Timing reference](https://tweens.gd/csharp/api/timing/)Every timing option, fill mode, and validation rule.