Lyra学习笔记 Experience流程梳理

目录

• 前言
• 1 创建
• 2 加载
• 3 Deactivate
• 4 总结与图示

  前言

  这篇主要将视角放在Experience的流程，所以不会涉及一些更深的东西

  之后ULyraExperienceManagerComponent简称为EMC

  1 创建

  完事开头难，首先找到了管理Experience的组件，那么它的初始化位置在哪？

  其作为ALyraGameState的成员，在构造函数中用CreateDefaultSubobject创建。

  //LyraGameState.h
  private:
  	// Handles loading and managing the current gameplay experience
  	UPROPERTY()
  	TObjectPtr
  	ExperienceManagerComponent;
  //LyraGameState.cpp
  ALyraGameState::ALyraGameState(const FObjectInitializer& ObjectInitializer)
  	: Super(ObjectInitializer)
  {
  	...
  	ExperienceManagerComponent = CreateDefaultSubobject(TEXT("ExperienceManagerComponent"));
  	...
  }
  

  2 加载

  结合EMC中的这个枚举梳理，初始为Unloaded：

  //LyraExperienceManagerComponent.h
  ELyraExperienceLoadState LoadState = ELyraExperienceLoadState::Unloaded;
  //其定义
  enum class ELyraExperienceLoadState
  {
  	Unloaded,
  	Loading,
  	LoadingGameFeatures,
  	LoadingChaosTestingDelay,
  	ExecutingActions,
  	Loaded,
  	Deactivating
  };
  

  结合之前的地图加载流程分析，加载的流程开始于ULyraExperienceManagerComponent::SetCurrentExperience->

  ULyraExperienceManagerComponent::StartExperienceLoad中LoadState转为Loading->

  ULyraExperienceManagerComponent::OnExperienceLoadComplete中收集完所有的GameFeaturesToEnable后，LoadState 转为LoadingGameFeatures->

  对于每个GF，执行ULyraExperienceManager::NotifyOfPluginActivation和UGameFeaturesSubsystem::Get().LoadAndActivateGameFeaturePlugin->

  先忽略测试用状态LoadingChaosTestingDelay

  ULyraExperienceManagerComponent::OnExperienceFullLoadCompleted中状态转为ExecutingActions并开始执行Actions，执行顺序为Experience本身Acitons中的每一个Action、遍历ActionSets，每一个ActionSets的Actions的每一个Action，对于单个Action，顺序执行OnGameFeatureRegistering()、OnGameFeatureLoading()、OnGameFeatureActivating(Context)->

  Action执行完成后，状态进入Loaded，然后分别是OnExperienceLoaded三个优先级的多播

  3 Deactivate

  EndPlay触发DeActive->

  DeActive涉及的GameFeature->

  状态转为Deactivating->

  同理按顺序触发每个Action的OnGameFeatureDeactivating、OnGameFeatureUnregistering()->

  状态转为Unloaded ，CurrentExperience = nullptr;

  4 总结与图示