学步园

转载网址：http://blog.csdn.net/libeifs/article/details/7310962

1.  简介物件组成

2.  AssetBundle

3.  打包和读取

1.简介物件组成

这是羽化做的一个粗略图，其中各个组成部分除了工程以外都能通过AssetBundle打成一个后缀名为.unity3d的外部资源包，通过Unity自身的高压技术，最多能节约60%~70%的资源容量。

2.AssetBundle

        官方有自带的AssetBundle的例子，羽化通过这个例子改成了自己的一个小工程，通过AssetBundle的打包处理的好处在于把自身的依赖关系包括数据结构合理的分配完整，这样不需要开发者自己去给下载或者加载的资源控制路径，大大降低了开发大型在线游戏的门槛，同时越来越细的封包可以减少游戏的总体大小，资源最大化利用，对于小游戏也带来了很大帮助，可惜按照官方的说法是目前不能完全支持移动端。

AssetBundle具体使用方法在手册上写得很详细，圣典里也有详细的中文说明，羽化就不多说废话，需要注意的是AssetBundle的读取，虽然资源基本上都是用简单读取，但在特殊情况下会去读取特定unity3d包中的特定贴图，或者说是模型，这里就必须注意打包的结构，因为读取出来的是一个Object数组，可以使用Load读取特定资源。

3. 打包和读取

        打包方式是在Project视图下选择AutomatedExportResources，过程是自动完成，Unity的Editor类中提供了很多有趣的方法可以实现不同的打包操作，官方只给了手选打包和自动打包两种，但都不够智能。

AutomatedExportResources.js

<SPAN style="FONT-SIZE: 16px">@MenuItem("Assets/Auto Build Resource Files")  
static function ExportResource ()   
{  
    System.IO.Directory.CreateDirectory("AssetBundles");  
  
    var options = BuildAssetBundleOptions.CollectDependencies | BuildAssetBundleOptions.CompleteAssets;  
      
    BuildPipeline.PushAssetDependencies();  
    /*Effects*/  
    BuildPipeline.BuildAssetBundle(AssetDatabase.LoadMainAssetAtPath("Assets/Standard Assets/Data/Texture/Effects/Hit/Hit1.tga"), null, "AssetBundles/Data/Texture/Effects/Hit/Hit1.unity3d", options);  
    BuildPipeline.BuildAssetBundle(AssetDatabase.LoadMainAssetAtPath("Assets/Standard Assets/Data/Texture/Effects/Hit/Hit2.tga"), null, "AssetBundles/Data/Texture/Effects/Hit/Hit2.unity3d", options);       
    BuildPipeline.BuildAssetBundle(AssetDatabase.LoadMainAssetAtPath("Assets/Standard Assets/Data/Model/Effects/Hit/Hit1.fbx"), null, "AssetBundles/Data/Model/Effects/Hit/Hit1.unity3d", options);   
    BuildPipeline.BuildAssetBundle(AssetDatabase.LoadMainAssetAtPath("Assets/Standard Assets/Data/Model/Effects/Hit/Hit2.fbx"), null, "AssetBundles/Data/Model/Effects/Hit/Hit2.unity3d", options);   
    BuildPipeline.BuildAssetBundle(AssetDatabase.LoadMainAssetAtPath("Assets/Standard Assets/Data/Material/Effects/Hit/Hit1.mat"), null, "AssetBundles/Data/Material/Effects/Hit/Hit1.unity3d", options);     
    BuildPipeline.BuildAssetBundle(AssetDatabase.LoadMainAssetAtPath("Assets/Standard Assets/Data/Material/Effects/Hit/Hit2.mat"), null, "AssetBundles/Data/Material/Effects/Hit/Hit2.unity3d", options);     
  
        BuildPipeline.PushAssetDependencies();  
            BuildPipeline.BuildAssetBundle(AssetDatabase.LoadMainAssetAtPath("Assets/Standard Assets/Data/Prefab/Effects/Hit/Hit1.prefab"), null, "AssetBundles/Data/Prefab/Effects/Hit/Hit1.unity3d", options);      
        BuildPipeline.PopAssetDependencies();  
        BuildPipeline.PushAssetDependencies();  
            BuildPipeline.BuildAssetBundle(AssetDatabase.LoadMainAssetAtPath("Assets/Standard Assets/Data/Prefab/Effects/Hit/Hit2.prefab"), null, "AssetBundles/Data/Prefab/Effects/Hit/Hit2.unity3d", options);  
        BuildPipeline.PopAssetDependencies();  
        BuildPipeline.PushAssetDependencies();  
            BuildPipeline.BuildAssetBundle(AssetDatabase.LoadMainAssetAtPath("Assets/Standard Assets/Data/Prefab/Effects/Hit/Hit3.prefab"), null, "AssetBundles/Data/Prefab/Effects/Hit/Hit3.unity3d", options);  
        BuildPipeline.PopAssetDependencies();  
        BuildPipeline.PushAssetDependencies();  
            BuildPipeline.BuildAssetBundle(AssetDatabase.LoadMainAssetAtPath("Assets/Standard Assets/Data/Prefab/Effects/Hit/Hit3.prefab"), null, "AssetBundles/Data/Prefab/Effects/Hit/Hit3.unity3d", options);  
        BuildPipeline.PopAssetDependencies();  
      
    BuildPipeline.PopAssetDependencies();  

Prefab.js

<SPAN style="FONT-SIZE: 16px">var download : WWW;  
var url = "packed_resource.unity3d";  
var resourcePath = "Lerpz";  
var guiOffset = 20;  
var assetBundle : AssetBundle;  
var instanced : Object;  
  
function StartDownload () {  
    if (url.IndexOf ("file://") == 0 || url.IndexOf ("http://") == 0)  
        download = new WWW (url);  
    else if (Application.platform == RuntimePlatform.OSXWebPlayer || Application.platform == RuntimePlatform.WindowsWebPlayer)  
        download = new WWW ("../AssetBundles/" + url);  
    else if (Application.platform == RuntimePlatform.OSXEditor || Application.platform == RuntimePlatform.WindowsEditor)  
        download = new WWW ("file://" + Application.dataPath + "/../AssetBundles/" + url);  
      
    yield download;  
      
    assetBundle = download.assetBundle;  
  
    if (assetBundle != null)  
    {  
        // Alternatively you can also load an asset by name (assetBundle.Load("my asset name"))   
        var go : Object = assetBundle.mainAsset;  
              
        if (go != null)  
        {  
            instanced = Instantiate(go);  
        }  
        else  
            Debug.Log("Couldnt load resource");   
    }  
    else  
    {  
        Debug.Log("Couldnt load resource");   
    }  
}  
  
  
function OnGUI()  
{  
    GUILayout.Space(guiOffset);  
    GUILayout.BeginHorizontal();  
    if (download == null)  
    {  
          
        if (GUILayout.Button("Download " + url))  
            StartDownload();      
    }  
    else  
    {  
        if (download.error == null)  
        {  
            var progress = parseInt(download.progress * 100);  
            GUILayout.Label(progress + "%");      
              
            if (download.isDone && GUILayout.Button("Unload Resource")  )  
            {  
                // Destroy the instantiated object   
                Destroy(instanced);  
                // Dispose the WWW class   
                // (This happens automatically from the GC, but you can do it explicitly to make sure it happens early on)   
                download.Dispose();  
                download = null;  
  
                // Unload the whole asset bundles and any loaded assets   
                assetBundle.Unload (true);  
                assetBundle = null;  
            }  
        }  
        else  
        {  
            GUILayout.Label(download.error);          
        }     
    }  
    GUILayout.EndHorizontal();  
}</SPAN>