ClientServer/Client/Assets/Models/PolygonAncientEmpire/Optimized/SorterByMaterial.cs

using System;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;

namespace Content.PolygonAncientEmpire.Optimized
{
    public class SorterByMaterial : MonoBehaviour
    {
        public List<Material> indexation = new List<Material>();

        [ContextMenu("SortObjectsBy")]
        public void SortAllObjectsByMaterial()
        {
            Dictionary<string, GameObject> objects = new Dictionary<string, GameObject>();
            List<MeshRenderer> renderers = transform.GetComponentsInChildren<MeshRenderer>().ToList();
            foreach (var mesh in renderers)
            {
                var materials = mesh.sharedMaterials;
                List<int> el = new List<int>();
                foreach (var mat in materials)
                    el.Add(indexation.IndexOf(mat));
                el.Sort();
                var nameOfRoot = "Mat:";
                foreach (var index in el)
                    nameOfRoot += $" {index}";
                if (objects.TryGetValue(nameOfRoot, out var rooted))
                    mesh.gameObject.transform.parent = rooted.transform;
                else
                {
                    GameObject materialGroup = new GameObject(nameOfRoot);
                    materialGroup.transform.parent = transform;
                    objects.Add(nameOfRoot, materialGroup);
                    mesh.gameObject.transform.parent = materialGroup.transform;
                }
            }
        }

        [ContextMenu("SortObjectsByMaterials")]
        public void SortObjectsByMaterial()
        {
            Dictionary<string, GameObject> objects = new Dictionary<string, GameObject>();
            List<MeshRenderer> renderers = new List<MeshRenderer>();
            for (int i = 0; i < transform.childCount; i++)
            {
                Transform child = transform.GetChild(i);
                try
                {
                    var mesh = child.GetComponent<MeshRenderer>();
                    if (mesh) renderers.Add(mesh);
                }
                catch (Exception e)
                {
                    Debug.Log(e.Message);
                }
            }

            foreach (var mesh in renderers)
            {
                var materials = mesh.sharedMaterials;
                List<int> el = new List<int>();
                foreach (var mat in materials)
                    el.Add(indexation.IndexOf(mat));
                el.Sort();
                var nameOfRoot = "Mat:";
                foreach (var index in el)
                    nameOfRoot += $" {index}";
                if (objects.TryGetValue(nameOfRoot, out var rooted))
                    mesh.gameObject.transform.parent = rooted.transform;
                else
                {
                    GameObject materialGroup = new GameObject(nameOfRoot);
                    materialGroup.transform.parent = transform;
                    objects.Add(nameOfRoot, materialGroup);
                    mesh.gameObject.transform.parent = materialGroup.transform;
                }
            }
        }
    }
}