Motion

Description

Stores a reference to an animation asset associated with a State Machine state.

The Motion class acts as an abstraction for APIs that accept either the AnimationClip or BlendTree animation classes.

Additional resources: AnimatorState.motion, AnimatorController.AddMotion, BlendTree.AddChild.

This example demonstrates how to create a BlendTree from a selection of AnimationClips. This example also demonstrates how a BlendTree is composed of two or more child Motions, and how to use a BlendTree to instantiate an AnimatorState.

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

static class MotionClassExample
{
    [MenuItem("Example/Create Animator Controller From Selected Clips")]
    static void CreateAnimatorControllerFromClips()
    {
        // Get the Motion-derived assets in the selection. You can only do this with AnimationClip assets.
        var motions = new List<Motion>();
        foreach (var obj in Selection.objects)
        {
            if (obj is Motion clip)
            {
                motions.Add(clip);
            }
        }

        if (motions.Count == 0)
        {
            Debug.LogWarning("No clips selected");
            return;
        }

        // Create an AnimationController in the project.
        var animatorController =
            AnimatorController.CreateAnimatorControllerAtPath(
                AssetDatabase.GenerateUniqueAssetPath("Assets/MotionExample.controller"));

        // Create a BlendTree that blends between the selected Motion objects.
        var blendTree = new BlendTree { name = "Default" };
        for (var i = 0; i < motions.Count; i++)
        {
            var clip = motions[i];
            blendTree.AddChild(clip, (float)i / motions.Count);
        }

        // Create a new state from the BlendTree (which is itself a Motion).
        animatorController.AddMotion(blendTree);

        // Make sure the BlendTree is persisted.
        AssetDatabase.AddObjectToAsset(blendTree, animatorController);

        // Show the new  AnimatorController in the project window.
        Selection.activeObject = animatorController;
        EditorGUIUtility.PingObject(animatorController);
    }
}

Inherited Members