AssetBundle

Unity

AssetBundle

设置资源AB

基本上unity所包含的资源文件，除了脚本文件都可以设置成ab资源。

生成AB资产

生成AB有两种方式

• 自定义打包
• AssetBundles-Browser-master插件

1. 预览AB

这里使用插件打包，对于目前所有ab资源一目了然，如有ab设置错误也会有错误提示，我们已经设置好ab资源用它打开如图

正是因为unity支持‘/’来分层，所以我们用文件层次来设置ab名称

才使得对应ab包层级目录结构清晰明确

2. 打包设置

enter description here

根据当前ab资源选择不同压缩模式比较

压缩模式	UnCompression	LZ4	LZMA
Andriod平台大小	325kb	160kb	119kb

• LZ4 解压读取速度快（推荐）
• LZMA 压缩率高，文件占用空间小，解压比较慢

获取AB加载

大致流程图示

下面示例从服务器中获取 tom ab资源一系列流程

要测试在服务中的ab资源

enter description here

测试代码

1.连接服务器，获取主依赖

调用入口

StartCoroutine(GetDepends(host, "AB_Andriod_LZ4"));

具体实现

/// 
    /// 服务器地址    /// 
    string host = @"https://ab-test-1258795305.cos.ap-shanghai.myqcloud.com/";    /// 
    /// ab-依赖    /// 
    public Dictionary
       
         dic_AB = new Dictionary
        
         ();    /// 
         
    /// 获取主依赖，本地存储依赖关系，下载全部ab    /// 
    /// 
         服务器根地址    /// 
         服务器下ab根文件名，以及主ab文件名称    /// 
             IEnumerator GetDepends(string host_path, string dir_name)    {        dic_AB.Clear();        //目录跟路径        string root_path = host_path + "/" + dir_name;        //获取主ab，拿到manifest获取依赖关系        AssetBundleManifest assetBundleManifestServer = null;  //服务器 总的依赖关系            UnityWebRequest ServerManifestWWW = UnityWebRequestAssetBundle.GetAssetBundle(root_path + "/" + dir_name);        Debug.Log("HTTP : " + ServerManifestWWW.url.ToString());        yield return ServerManifestWWW.SendWebRequest();        assetBundleManifestServer = (AssetBundleManifest)DownloadHandlerAssetBundle.GetContent(ServerManifestWWW).LoadAsset("AssetBundleManifest");        //存储各依赖关系        string[] depends_name = assetBundleManifestServer.GetAllAssetBundles();        for (int i = 0; i < depends_name.Length; i++)        {            AB_DATA ab_data = new AB_DATA();            ab_data.name = depends_name[i];                        UnityWebRequest target_uwq = UnityWebRequestAssetBundle.GetAssetBundle(Path.Combine(root_path, ab_data.name));            yield return target_uwq.SendWebRequest();            if (target_uwq.isDone)            {                //下载ab到本地                StartCoroutine(DownLoadAssetBundelAbdSave(Path.Combine(root_path, ab_data.name)));                //depends                var depends = assetBundleManifestServer.GetAllDependencies(ab_data.name);                ab_data.depends_name = new string[depends.Length];                for (int j = 0; j < depends.Length; j++)                {                    ab_data.depends_name[j] = depends[j];                }                dic_AB.Add(depends_name[i], ab_data);            }        }    }
        
       

2.缓存已下载的ab资源

/// 
    /// 下载AB文件并保存到本地    /// 
    /// 
           IEnumerator DownLoadAssetBundelAbdSave(string url)    {        WWW www = new WWW(url);        yield return www;        if (www.isDone)        {            //表示资源下载完毕使用IO技术把www对象存储到本地            SaveAssetBundle(Path.GetFileName(url), www.bytes, www.bytes.Length);        }    }    /// 
    /// 存储AB文件到本地    /// 
    private void SaveAssetBundle(string fileName, byte[] bytes, int count)    {        string dir_path = Application.persistentDataPath + "/" + fileName;        Debug.Log("存储路径 ： " + dir_path);        Stream sw = null;        FileInfo fileInfo = new FileInfo(dir_path);        sw = fileInfo.Create();        sw.Write(bytes, 0, count);        sw.Flush();        sw.Close();        sw.Dispose();        Debug.Log(fileName + "下载并存储完成");    }

3.从本地磁盘读取ab并实例化

调用入口

private void LoadStream_OnClick()    {        //设置要加载的目标物体名        string ab_name = "tom.prefab";                string dir_path = Application.persistentDataPath + "/" + ab_name;        //从已缓存的字节文件中加载tom        StartCoroutine(LoadABFormStream(dir_path));        //加载tom所需的依赖        string[] ad_names = dic_AB[ab_name].depends_name;        for (int i = 0; i < ad_names.Length; i++)        {            string dir_path_depends = Path.Combine(Application.persistentDataPath, ad_names[i]);           //加载依赖时，直接加载出其ab包即可，不需要分解其依赖类型再去实例，unity自会处理            AssetBundle.LoadFromFile(dir_path_depends);           //所以下面部分就不需要了           // StartCoroutine(LoadABFormStream(dir_path_depends));        }    }

相关方式实现

/// 
    /// 从字节文件读取ab，并且实例化    /// 
    ///     /// 
           IEnumerator LoadABFormStream(string dir_path)    {        FileStream fileStream = new FileStream(dir_path, FileMode.Open, FileAccess.Read);        AssetBundleCreateRequest request = AssetBundle.LoadFromStreamAsync(fileStream);        yield return request;        AssetBundle myLoadedAssetBundle = request.assetBundle;        if (myLoadedAssetBundle == null)        {            Debug.Log("Failed to load AssetBundle!");            yield break;        }        //实例化ab        InstanceAB_FormAssetBundle(myLoadedAssetBundle, myLoadedAssetBundle.name);        fileStream.Close();    }     private void InstanceAB_FormAssetBundle(AssetBundle assetBundle, string obj_name)    {        Object gameObject = null;        if (obj_name.Contains(".mat"))        {            gameObject = assetBundle.LoadAsset
       
        (obj_name);            Instantiate
        
         ((Material)gameObject);        }        else if (obj_name.Contains(".prefab"))        {            gameObject = assetBundle.LoadAsset
         
          (obj_name);            Instantiate
          
           ((GameObject)gameObject);        }    }