Writing a script to play an additive animation when a character is controlled by timeline.

Unity Engine
, ,
1

Hi,

When a character’s animation and transformation are controlled by timeline, is it possible to write a script that when pressing a key, it plays an additive animation on that character?

Let say timeline is controlling character walking from one position to the other. During that time, if I press spacebar, the character would wave his hand while walking.

Is this possible?

2

That question is better asked on the Timeline forum: Unity Engine - Unity Discussions

3

Yes, it is possible, although it’s not possible to do on the animation track itself. But you can do it by manipulating the underlying playable graph once it is created.

Here’s a sample that should help you get started. It adds an additive layer to a timeline animation track via script that attaches to a playable director.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Animations;
using UnityEngine.Playables;

[ExecuteInEditMode]
[RequireComponent(typeof(PlayableDirector))]
public class PlayAdditive : MonoBehaviour
{
    private AnimationClipPlayable clipPlayable;

    public AnimationClip clip;
    public AvatarMask mask;
    public Animator who;

    private double startTime;


    void Update()
    {
        if (clip == null || who == null)
            return;

        if (!clipPlayable.IsValid())
        {
            var graph = GetComponent<PlayableDirector>().playableGraph;
            if (graph.IsValid())
            {
                startTime = graph.GetRootPlayable(0).GetTime(); // capture the current time
            }

            for (int i = 0; i < graph.GetOutputCount(); i++)
            {
                var output = (AnimationPlayableOutput) graph.GetOutputByType<AnimationPlayableOutput>(i);
                if (output.GetTarget() == who)
                {
                    // get the root of the playable graph
                    var outputPlayable = output.GetSourcePlayable().GetInput(output.GetSourceOutputPort());

                    // search the subgraph for the layer mixer
                    while (outputPlayable.GetInputCount() > 0 && !outputPlayable.IsPlayableOfType<AnimationLayerMixerPlayable>())
                        outputPlayable = outputPlayable.GetInput(0);

                    if (outputPlayable.IsValid())
                    {
                        var layerMixer = (AnimationLayerMixerPlayable) outputPlayable;
                        clipPlayable = AnimationClipPlayable.Create(graph, clip);
                        var inputIndex = layerMixer.AddInput(clipPlayable, 0, 1);

                        layerMixer.SetLayerAdditive((uint) inputIndex, true);
                        layerMixer.SetLayerMaskFromAvatarMask((uint)inputIndex, mask);

                        startTime = GetComponent<PlayableDirector>().time;
                    }
                }
            }
        }

        if (clipPlayable.IsValid())
        {
            clipPlayable.SetTime(GetComponent<PlayableDirector>().time - startTime);
        }

    }
}
4

:slight_smile: