本身也具有一些unity知识，包括Eidtor界面使用、Shader效果实现、性能分析，但对C#、游戏逻辑不太清楚，这次想从开发者角度理解游戏，提高C#编程，从简单的unity游戏理解游戏逻辑，更好的为工作服务。

unity2019.4.40f1c1，使用Unity官网FPS Microgame（如下图）。原本想从游戏源码启动流程开始学习，但Unity核心代码没有开源，就还是先理解游戏逻辑。

游戏分成 5个Scene，我们关注MainScene，其中有个GameManager，从Inspector看挂有许多Scripts，我们先一个个分析。

 GameFlowManager，引用using UnityEngine.SceneManagement，定义类GameFlowManager前半部分是在自定义Eidtor界面，这里float timeRatio = 1 - (m_TimeLoadEndGameScene - Time.time) / endSceneLoadDelay;不是很理解，待续

using UnityEngine;
using UnityEngine.SceneManagement;public class GameFlowManager : MonoBehaviour
{[Header("Parameters")][Tooltip("Duration of the fade-to-black at the end of the game")]public float endSceneLoadDelay = 3f;[Tooltip("The canvas group of the fade-to-black screen")]public CanvasGroup endGameFadeCanvasGroup;[Header("Win")][Tooltip("This string has to be the name of the scene you want to load when winning")]public string winSceneName = "WinScene";[Tooltip("Duration of delay before the fade-to-black, if winning")]public float delayBeforeFadeToBlack = 4f;[Tooltip("Duration of delay before the win message")]public float delayBeforeWinMessage = 2f;[Tooltip("Sound played on win")]public AudioClip victorySound;[Tooltip("Prefab for the win game message")]public GameObject WinGameMessagePrefab;[Header("Lose")][Tooltip("This string has to be the name of the scene you want to load when losing")]public string loseSceneName = "LoseScene";public bool gameIsEnding { get; private set; }PlayerCharacterController m_Player;NotificationHUDManager m_NotificationHUDManager;ObjectiveManager m_ObjectiveManager;float m_TimeLoadEndGameScene;string m_SceneToLoad;void Start(){   Debug.Log("Start Game: " + m_Player);//返回场景中的所填类型的随机个体m_Player = FindObjectOfType<PlayerCharacterController>();//DebugUtility.cs不是Unity中的内置脚本,存在Assets/FPS/Scripts/DebugUtility.csDebugUtility.HandleErrorIfNullFindObject<PlayerCharacterController, GameFlowManager>(m_Player, this);m_ObjectiveManager = FindObjectOfType<ObjectiveManager>();DebugUtility.HandleErrorIfNullFindObject<ObjectiveManager, GameFlowManager>(m_ObjectiveManager, this);AudioUtility.SetMasterVolume(1);}void Update(){if (gameIsEnding){   Debug.Log("m_TimeLoadEndGameScene: " + m_TimeLoadEndGameScene);Debug.Log("Time.time: " + Time.time);Debug.Log("endSceneLoadDelay: " + endSceneLoadDelay);float timeRatio = 1 - (m_TimeLoadEndGameScene - Time.time) / endSceneLoadDelay;Debug.Log("timeRatio: " + timeRatio);endGameFadeCanvasGroup.alpha = timeRatio;AudioUtility.SetMasterVolume(1 - timeRatio);// See if it's time to load the  (after the delay)if (Time.time >= m_TimeLoadEndGameScene){Debug.Log("Scene loading: " + m_SceneToLoad);SceneManager.LoadScene(m_SceneToLoad);gameIsEnding = false;}}else{if (m_ObjectiveManager.AreAllObjectivesCompleted())EndGame(true);// Test if player diedif (m_Player.isDead)EndGame(false);}}void EndGame(bool win){// unlocks the cursor before leaving the scene, to be able to click buttonsCursor.lockState = CursorLockMode.None;Cursor.visible = true;// Remember that we need to load the appropriate end scene after a delaygameIsEnding = true;endGameFadeCanvasGroup.gameObject.SetActive(true);if (win){m_SceneToLoad = winSceneName;m_TimeLoadEndGameScene = Time.time + endSceneLoadDelay + delayBeforeFadeToBlack;// play a sound on winvar audioSource = gameObject.AddComponent<AudioSource>();audioSource.clip = victorySound;audioSource.playOnAwake = false;audioSource.outputAudioMixerGroup = AudioUtility.GetAudioGroup(AudioUtility.AudioGroups.HUDVictory);audioSource.PlayScheduled(AudioSettings.dspTime + delayBeforeWinMessage);// create a game messagevar message = Instantiate(WinGameMessagePrefab).GetComponent<DisplayMessage>();if (message){message.delayBeforeShowing = delayBeforeWinMessage;message.GetComponent<Transform>().SetAsLastSibling();}}else{m_SceneToLoad = loseSceneName;m_TimeLoadEndGameScene = Time.time + endSceneLoadDelay;}}
}