SetDuration of playable asset

Unity Engine
,
1

I have a:

  • PlayableAsset, called DialogClip. It has a public string and an AudioClip.
  • TrackAsset, called DialogTrack.
  • PlayableBehaviour, called DialogBehaviour
  • PlayableBehaviour, called DialogMixer

Because there is a public audioclip in DialogClip, I’m able to drag an audio clip right onto the timeline - which is awesome.

However, the duration always defaults to 5 seconds. I would like the default duration to be the duration of the audio clip. I would have thought using PlayableExtensions.SetDuration(audioClip.length) would do the trick - but it doesn’t.

How do I set the duration of a clip?

using UnityEngine;
using UnityEngine.Playables;

public class DialogClip : PlayableAsset
{
    [TextArea(2, 10)]
    public string captionText;
    public AudioClip audioClip;

    public override Playable CreatePlayable(PlayableGraph graph, GameObject owner)
    {
        var playable = ScriptPlayable<DialogBehaviour>.Create(graph);
       
        DialogBehaviour dialogBehaviour = playable.GetBehaviour();

        dialogBehaviour.captionText = captionText;
        dialogBehaviour.audioClip = audioClip;
        playable.SetDuration(audioClip.length);  ///////// this seems to do nothing

        return playable;
    }
}

using UnityEngine;
using UnityEngine.Playables;

public class DialogBehaviour : PlayableBehaviour
{
    public string captionText;
    public AudioClip audioClip;
}

using UnityEngine.Playables;

public class DialogMixer : PlayableBehaviour
{
    public override void ProcessFrame(Playable playable, FrameData info, object playerData)
    {
        ActorManager actor = playerData as ActorManager;

        string currentText = "";
        float currentAlpha = 0f;

        if (!actor) { return; }



        int inputCount = playable.GetInputCount();
        for (int i = 0; i < inputCount; i++)
        {
            float inputWeight = playable.GetInputWeight(i);

            if (inputWeight > 0f)
            {
                ScriptPlayable<DialogBehaviour> inputPlayable = (ScriptPlayable<DialogBehaviour>)playable.GetInput(i);

                DialogBehaviour dialog = inputPlayable.GetBehaviour();
                currentText = dialog.captionText;
                currentAlpha = inputWeight;
            }
        }

        actor.speechBubble.captionText.text = currentText;
        actor.speechBubble.canvasGroup.alpha = currentAlpha;
    }
}

using UnityEngine;
using UnityEngine.Playables;
using UnityEngine.Timeline;

[TrackBindingType(typeof(ActorManager))]
[TrackClipType(typeof(DialogClip))]
public class DialogTrack : TrackAsset
{
    public override Playable CreateTrackMixer(PlayableGraph graph, GameObject go, int inputCount)
    {
        ScriptPlayable<DialogMixer> scriptPlayable = ScriptPlayable<DialogMixer>.Create(graph, inputCount);       

        return scriptPlayable;
    }
}
2

You need to set the duration of the PlayableAsset, not the duration of the Playable.

Here would probably be the best place.

3

Thank you for responding so quickly.

I’m having troubles figuring out how to call OnCreateClip(Timeline.TimelineClip clip) on my DialogClip PlayableAsset.

Where should that go?

4

You need to implement it on the TrackAsset, not on the clip itself. It should be called automatically when a TimelineClip is created on your track.

From there, you can access both the container (TimelineClip) and the contents (PlayableAsset)

5

If what you want is for your PlayableAsset to always have the same duration as your AudioClip, you should override
PlayableAsset.duration, and return the duration of your AudioClip.

6

Thank you again. I’m a little closer now. Still struggling, but closer…

In my TrackAsset, I figured out how to do a protected override. With it, I’ve been able to change the default duration:

public class DialogTrack : TrackAsset
{
    ScriptPlayable<DialogMixer> scriptPlayable;
    float clipDuration = 1f; // 1 is a temp value

    public override Playable CreateTrackMixer(PlayableGraph graph, GameObject go, int inputCount)
    {
        scriptPlayable = ScriptPlayable<DialogMixer>.Create(graph, inputCount);      
        return scriptPlayable;
    }

    protected override void OnCreateClip(TimelineClip clip)
    {
        clip.duration = clipDuration;
        base.OnCreateClip(clip);
    }
}

The good news is, my clips are now defaulting to 1 second.
The bad news is, I can’t figure out how to reference a value on the playable to assign the clip.duration.

7

Looks like we were typing at the same time…

Yes, that’s exactly what I’m trying to do.