Unity Helper script to speed up setting up the required gameobject hierarchy for the Gley Traffic System (v3 as of this post)

NewVehicleCreator.cs

/*
 * Licensed under the MIT license
 *
 * MIT License
 * Copyright (c) 2025 Mike Wuetherick
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
using Gley.TrafficSystem;
using Gley.UrbanSystem.Internal;
using UnityEngine;

namespace PixelWizards.Gameplay.TrafficSystem
{
    /// <summary>
    /// Sdd into a scripts folder
    /// Helper to speed setup of vehicles for the Gley Traffic System (v3)
    /// </summary>
    public class NewVehicleCreator : MonoBehaviour
    {
        [SerializeField]
        private GameObject mainVehiclePrefab;
       
        public GameObject VehiclePrefab => mainVehiclePrefab;
        
        public void SetupNewVehicle()
        {
            if (gameObject.GetComponent<VehicleComponent>() != null)
            {
                // vehicle is already setup, verify 
                Debug.Log("Vehicle Already setup? Validating...");
            }
        
            // car holder
            var ch = ValidateElement("CarHolder", transform);
            
            // wheels
            ValidateElement("CarHolder/Wheels", ch);
            
            // body
            var body = ValidateElement("CarHolder/Body", ch);
            if (mainVehiclePrefab)
            {
                // parent the vehicle under the body for now
                mainVehiclePrefab.transform.parent = body.transform;
                mainVehiclePrefab.transform.localPosition = Vector3.zero;
            }
            else
            {
                Debug.Log("Missing vehicle prefab, parent under 'Body' object!");
            }
            
            // lights
            var lights = ValidateElement("CarHolder/Lights", ch);

            ValidateElement("CarHolder/Lights/BlinkersLeft", lights);
            ValidateElement("CarHolder/Lights/BlinkersRight", lights);
            ValidateElement("CarHolder/Lights/FrontLights", lights);
            ValidateElement("CarHolder/Lights/RearLights", lights);
            ValidateElement("CarHolder/Lights/ReverseLights", lights);
            ValidateElement("CarHolder/Lights/StopLights", lights);
            
            // colliders
            ValidateElement("CarHolder/Colliders", ch);

            // front trigger
            ValidateElement("CarHolder/FrontTriggerHolder", ch);

            // setup the vehicle components
            if (!gameObject.TryGetComponent(out Rigidbody rb))
            {
                Debug.Log("Missing rigidbody, adding...");
                gameObject.AddComponent<Rigidbody>();
            }
            if (!gameObject.TryGetComponent(out VehicleComponent vh))
            {
                Debug.Log("Missing VehicleComponent, adding...");
                gameObject.AddComponent<VehicleComponent>();
            }
            if (!gameObject.TryGetComponent(out EngineSoundComponent esc))
            {
                Debug.Log("Missing EngineSoundComponent, adding...");
                gameObject.AddComponent<EngineSoundComponent>();
            }
            if (!gameObject.TryGetComponent(out VehicleLightsComponent vlc))
            {
                Debug.Log("Missing VehicleLightComponent, adding...");
                gameObject.AddComponent<VehicleLightsComponent>();
            }
            Debug.Log("Vehicle configured properly!");
        }

        public Transform ValidateElement(string name, Transform parent)
        {
            var existing = transform.Find(name);
            // does an object with this name exist?
            if (existing)
            {
                Debug.Log($"Element: {name} exists, checking parent...");
                // check if it has the correct parent
                if (existing.parent == parent)
                {
                    return existing;
                }
                
                Debug.Log($"Element: {name}, invalid parent, updating to {parent.name}");
                existing.SetParent(parent);
                existing.transform.localPosition = Vector3.zero;
            }
            else
            {
                // extract the last name
                var elements = name.Split('/');
                var properName = elements[^1];
                Debug.Log($"Missing: {properName}, creating with parent {parent.name}");
                var go = new GameObject(properName);
                go.transform.SetParent(parent);
                go.transform.localPosition = Vector3.zero;
                existing = go.transform;
            }

            return existing;
        }
    }
}

NewVehicleCreatorEditor.cs

/*
 * Licensed under the MIT license
 *
 * MIT License
 * Copyright (c) 2025 Mike Wuetherick
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
using UnityEditor;
using UnityEngine;

namespace PixelWizards.Gameplay.TrafficSystem
{
    /// <summary>
    /// Custom inspector for the NewVehicleCreator
    /// Add into an 'Editor' folder (or asmdef) in your project
    /// </summary>
    [CustomEditor(typeof(NewVehicleCreator)), CanEditMultipleObjects]
    public class NewVehicleCreatorEditor : Editor
    {
        private static NewVehicleCreator entry;

        private void OnEnable()
        {
            entry = (NewVehicleCreator)target;
        }

        public override void OnInspectorGUI()
        {
            serializedObject.Update();
            DrawDefaultInspector();
            GUILayout.Label("Optional: specify a prefab for the vehicle, will parent under the 'Body'", EditorStyles.helpBox);
            GUILayout.Space(15);
            GUILayout.BeginHorizontal();
            {
                if (GUILayout.Button("Setup Vehicle"))
                {
                    entry.SetupNewVehicle();
                }
            }
            GUILayout.EndHorizontal();

            // we might have deleted ourselves, so check before applying any changes
            if (serializedObject != null)
            {
                serializedObject.ApplyModifiedProperties();    
            }
        }
    }
}

Added MIT license header