U3D官方视频笔记.md

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• U3D官方视频笔记
  • Project Management
    • Mid-size project must have
    • LevelManager
      • Why level manager ?
      • LevelManager Design
    • PoolManager
      • Design Rules for PoolManager
    • MVCS: STRANGEIOC
      • The structure of a binding -1
      • Types Of Binding
      • Dispatcher
      • Binding Interface & Implementation
    • MVVM: UFRAME
    • Other Tips
      • .gitignore file
      • Coding Standards
      • Art Resource Standards
      • Unity Test Tools
  • AssetBundle
    • 资源管理方式
    • AssetBundle
    • AssetBundel 打包
    • 依赖关系打包
    • 打包策略
    • 如何处理复杂依赖关系
    • 获取依赖关系
    • 正确的打包方式
    • 图的深度优先遍历
    • 保存依赖关系数据
    • AssetBundle 加载
    • 依赖关系加载
    • 依赖关系卸载
    • 5.0 AB 打包
      • 最小粒度打包
      • 更优的依赖关系打包
      • 5.0的简化过程
      • AssetBundlemanifest
      • 依赖关系加载
      • AssetBundle 的拆分
      • AssetBundle 的合并

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U3D官方视频笔记

Project Management

Manager of managers

• MainManager costomizes and manages all the submanagers
• Submanagers operate as singletons and can easily address each other or colaborate.

Submanagers:

EventManager	Streamline messaging between classes
AudioManager	COntrol audio playback from one place
GUIManager	centralize the controls to handle clicks , etc.
PoolManager	Persist perfab instances in RAM and display them as needed
LevelManager	Queue up levels and perfrom transitions between them.
GameManager	Manage the core game mechanics , usually project specific.
SaveManager	Save and load user preference and achievements
MenuManager	Controls all menus' animations,contents, and behaviors.

Mid-size project must have

• LevelManager
• PoolManager
• SaveManager

LevelManager

Why level manager ?

Issus 1: You need to know the scene name or the index of the scene which you want to load, but most probably the name or order will be changed later.

Application.LoadLevel("FirstLevel");
Application.LoadLevel(1);

Issus 2: There's no simple method of passing arguments to a scene, eg, assuming you're resuing one scene for many different levels.

Application.LoadLevel("FirstLevel" , LevelArgs );

LevelManager Design

• Compose a configuration table
• Create a new API: LevelManager.LoadNext();
• manager the transitions between two levels easily

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PoolManager

A simple pool design:

• Maintain a list of dormant(暂时不用的) objects

private List<GameObject> dormantObjects = new List<GameObject>();

• The list contains all different types of game objects/perfabs
• Spawn(), Despawn(), Trim()

pubic GameObject Spawn( GameObject go ) {
    GameObject temp = nil;
    if (dormantObjects.Count > 0) {
        foreach ( GameObject dob in dormantObjects ) {
            if (dob.name == go.name) {
                // find an available GameObject
                temp = dob ;
                dormantObjects.Remove(temp);
                return temp ;
            } // end if dob.name
        } //end for
    } // end if
    
    //Now instantiate a new GameObject
    temp = GameObject.Instantiate(go) as GameObject ;
    temp.name = go.name ;
    return temp ;
} // end func

public void Despawn( GameObject go ) {
    go.transform.parent = PoolManager.transform ; // why shoud have this ?
    go.SetActive( false );
    dormantObjects.Add(go) ;
    Trim();
}

public void Trim() {
    while ( dormantObjects.Count > Capacity ) {
        GameObject dob = dormantObjects[0];
        dormantObjects.RemoveAt(0);
        Destroy( dob ) ;
    } // end while
} // end func

**A better design:

• PoolManger // top pool manager
  • SpawnPool // for a type of prefabs
    • PrefaPool // for a prefab
      • Active instances
      • Inactive instances

Design Rules for PoolManager

• As a singleston.
• Manage multiple SpawnPools.

For prefab pool:

• Create a PrefabPool for each prefab.
• Maintain a list of activated objects and another list of deactive objects.
• Centrally manager the Load/Unload process here.
• Avoid setting an instance limitation number
• if really necessary, follow the following rules:
  • Waits for 'cullDelay' in seconds and culls the 'despawned' list if above amount
  • cull less 5 instances each time
  • start a separate coroutine to do the culling work.

MVCS: STRANGEIOC

The structure of a binding -1

• Basic Structure
  • IBinder.Bind<Key>().To<Value>();
• The key triggers the value

Types Of Binding

Key	Value	Notes
event	callback	an event triggers a callback
interface	implementation	binds an interface to its implementation
class	dependent class	the instantiation of one class trigger the instantiation of its dependent class

Dispatcher

• Simple format
  • dispatcher.Dispatch( AttackEvent.FIRE_MISSILE );
• Event + Data
  • dispatcher.Dispatch( AttackEvent.FIRE_MISSILE, orientation )

Binding Interface & Implementation

interface IMonster {
    IWeapon weapon{get;set;}
}
class Monster:IMonster {
    [Inject]  // the magic word
    public IWeapon weapon{get;set;}
}

context.injectionBinder.Bind<IWeapon>().To<Gun>();
context.injectionBinder.Bind<IWeapon>().To<Cannon>();

• If you inject something, you have to map it, otherwise , it will result in null pointer errors
• Injection employs reflection, which is slow.

MVVM: UFRAME

---

Other Tips

.gitignore file

where to get ?

Coding Standards

• Use C#
• Naming conventions
  • Use descriptive name
• Logical folder structure
  • Use named empty game objects as scene folders
• Use cache
  • Cache component references , GetComponent<ComponentName>() is slow
  • Cache objects references , GameObject.Find() is very slow
  • Memory allocation with object pools
  • Use sharing materials

Art Resource Standards

• Reasonable & strict
• Automatic tools

Unity Test Tools

• Published by Unity
• Asset Store
• Free

---

AssetBundle

Asset: Mesh,Material,Texture, Audio,etc...

资源管理方式

• Assets
  • 只有被引用的资源会被打包
  • 适合存放静态资源
  • 不能动态加载
• Resources
  • 支持动态加载
  • Resources.assets文件 (2G限制)
  • 随安装包完全下载，无法动态更新
• StreamingAssets
  • 保持文件原始格式
    • 比如可以存放原始的jpg文件，而不导入成内部格式
  • 随安装包完全下载，无法动态更新
  • Application.streamingAssetsPath
• AssetBundle

·	动态加载	动态更新	本地缓存
Assets	No	No	N/A
Resources	Yes	No	N/A
AssetBundle	Yes	Yes	Yes
StreamingAssets	Yes	No	N/A

AssetBundle

• Asset 的集合
• 压缩(缺省)
• 动态加载
• 动态更新

AssetBundel 打包

依赖关系导致资源重复

• Cube-> Mat <- Cylinder
• Asset Bundle 1
  • Cube + Mat
• Asset Bundle 2
  • Cylinder + Mat

依赖关系打包

• Asset Bundle 1 : Cube
• Asset Bundle 2 : Cylinder
• Asset Bundle 3 : Mat

打包策略

• 尽可能的减少冗余资源
  • 减少 AppSize , 减少网络下载流量
• 分类打包
  • 按类型, 或者用途打包
• AssetBundle 大小尽量不超过1M
  • 较少 IO 压力

如何处理复杂依赖关系

获取依赖关系

public static string[] AssetDatabase.GetDependencies(string)

首先以每个资源为一个节点，以最低粒度构造有向图。

只考虑入度，直接打包 入度为0的资源，可以包含入度为1的资源。

但是入度 >= 2的资源有可能被重复打包:

正确的打包方式

入度为1的资源可以被自动打包到上一级的AB包中, 为避免入度为2的资源重复打包，需要将它单独放到一个AB包.

大多数情况，有向图会变得很复杂:

我们可以对有向图进行简化，入度为1的可以简化，入度为2或以上的为共享资源：

当前节点和父节点，共同拥有的依赖关系，可将2父节点的依赖关系删除, 比如 2 和 其父节点3 都依赖于 节点1，可以将 3-1的依赖关系删除:

图的深度优先遍历

入度为0的节点开始，遍历打包

保存依赖关系数据

依赖关系，加载的时候需要用到

AssetBundle 加载

• new WWW
• WWW.LoadFromCacheOrDownload
• AssetBundle.CreateFromMemory
• AssetBundle.CreateFromFile

依赖关系加载

需要先加载所依赖的AB包, 然后再加载自身。

依赖关系卸载

通过 Reference Count 来判断是否需要卸载一个AB包

5.0 AB 打包

BuildAssetBundle() 方法内部有处理依赖关系，但是不能完全避免资源重复.

最小粒度打包

可以直接使用该API，内置依赖关系处理

AssetBundleManifest.BuildAssetBundles

更优的依赖关系打包

• 仍需通过依赖关系图去分析
• 生成Asset 到AssetBundle的关系映射
• 分析结果生成AssetBundleBuild

5.0的简化过程

• 不再需要push / pop 依赖关系
• 不需要通过图的遍历逐个生成AB包
• 只需要找到入度为0和 入度>=2 的资源节点，一次性发送到BuildAssetBundles 处理

AssetBundlemanifest

依赖关系加载

AssetBundlemanifest.GetAllDependencies()
AssetBundlemanifest.GetDirectDependencies()

AssetBundle 的拆分

避免 AssetBundle 过大

AssetBundle 的合并

如果两个资源拥有相同的 入度和出度(资源)依赖，则可以合并: