Generate an AnimClip asset from a selection of Sprites at the ContextMenu

misc_AnimTools.cs

using UnityEditor;
using UnityEngine;

namespace Evolis3D.Utils
{
    [CanEditMultipleObjects]
    public class misc_AnimTools : MonoBehaviour
    {
        [MenuItem("Assets/!Evolis3D/Compound AnimClip with these...")]
        static void CompoundAnimClip()
        {
            var frames = Selection.GetFiltered<Sprite>(SelectionMode.ExcludePrefab);
            if (frames.Equals(null) || frames.Length < 1) return;
        
            Debug.Log($"<color=yellow>[CompoundClip]</color> Selected: {frames.Length.ToString()} sprites. <color=cyan>✓</color>");
            var clip = new AnimationClip();
            clip.frameRate = 1;
            clip.wrapMode = WrapMode.Loop; //by default loops
            
            var animClipSett = new AnimationClipSettings();
            animClipSett.loopTime = true;
     
            AnimationUtility.SetAnimationClipSettings(clip, animClipSett);
            
            var keys = new Keyframe[frames.Length];
        
            var spriteBinding = new EditorCurveBinding();
            spriteBinding.type = typeof(SpriteRenderer);
            spriteBinding.path = "";
            spriteBinding.propertyName = "m_Sprite";
            //spriteBinding.propertyName = "Sprite";
        
            var spriteKeyFrames = new ObjectReferenceKeyframe[frames.Length];
            for(int i = 0; i < (frames.Length); i++) {
                spriteKeyFrames[i] = new ObjectReferenceKeyframe();
                spriteKeyFrames[i].time = i/clip.frameRate;
                spriteKeyFrames[i].value = frames[i];
            }
            
            AnimationUtility.SetObjectReferenceCurve(clip, spriteBinding, spriteKeyFrames);
        
            var filepath = EditorUtility.SaveFilePanelInProject("Save AnimClip as...", "clip_xxx", "anim", "anim");
            if (filepath.Equals(null)) return;
            
            AssetDatabase.CreateAsset(clip,filepath);
            AssetDatabase.SaveAssets();
            AssetDatabase.Refresh();
            Debug.Log($"<color=yellow>[CompoundClip]</color> AnimClip asset generated. <color=cyan>✓</color>");
        }
    }
}