AssetBundle------ 资源打包和依赖资源打包

前段时间做了一个项目，刚好使用到了AssetBundle资源打包的东西，于是花了点时间研究了一下AssetBundle.

AssetBundle 打包

   我用NGUI插件加载了一张图片，并且把它拖拽为预制名为Texture3.prefab  和 Texture4.prefab .下面是我的打包函数

[MenuItem("Assets/Build AssetBundle From Selection - Track dependencies")]        static void ExportResource () {            // 打开保存面板，获得选择的路径             string path = EditorUtility.SaveFilePanel ("Save Resource", "", "New Resource", "unity3d");            if (path.Length != 0) {                // 选择要保存的对象                Object[] selection = Selection.GetFiltered(typeof(Object), SelectionMode.DeepAssets);                //开始打包                BuildPipeline.BuildAssetBundle(Selection.activeObject, selection, path, BuildAssetBundleOptions.CollectDependencies | BuildAssetBundleOptions.CompleteAssets,BuildTarget.StandaloneWindows);                //打包完成提示                EditorUtility.DisplayDialog("", "Build Completed", "OK");                //刷新资源目录                AssetDatabase.Refresh();            }        }

说明一下：  

1.我们打包的资源的后缀格式可以是 ".assetbundle" 或者 ".unity3d" 。笔者这里使用的是后者  

2. 解释一下打包函数的参数，第一个参数 Selection.activeObject 是我们打包的mainAsset ，

第二个参数 selection 是我们选择的对象过滤后的物体，可以为空，第三个参数 path 是 打包的资源的

保存路径 ，第四个参数是打包选项 ，我这里选用的两个选项 分别代表 打包所有有关联的对象和强制

打包全部的资源，详情请查找API文档 第五个参数是打包的平台。 

 

AssetBundle加载

下面是我写的加载函数：

public string[] textureName;// Use this for initializationvoid Start () {        for (int i = 0; i < textureName.Length; i++)        {            StartCoroutine(LoadAssetBundle(PlatflamPath() + textureName[i] + ".unity3d", textureName[i]));        }       }      static public IEnumerator LoadAssetBundle(string filepath,string assetName) {         WWW www = new WWW(filepath);        yield return www;        if (www == null) {            Debug.Log(" www is null ");        }        else if (www.error != null) {            Debug.Log("error " + www.error);        }        else if (www.isDone) {            AssetBundle assetBundle = www.assetBundle;            AssetBundleRequest requet = assetBundle.LoadAsync(assetName, typeof(GameObject));            yield return requet;            if (requet.isDone) {                GameObject obj = Instantiate(requet.asset) as GameObject;                }                    }        www.Dispose();        www = null;    }    static public string PlatflamPath()    {        return string.Format("file://{0}", Application.streamingAssetsPath) + "/";    }

AssetBundle依赖资源\共享资源打包

      上面的两个预制都是用了同一张图片，我们可以将这张图片打到没一个包里面去，我们上面将的就是这种情况。这样子做的话有些弊端，比如内存有点让费，并且当这张图片有所改变的时候，两个包需要重新打包。当然，我们也可以使用AssetBundle的依赖资源\共享资源进行打包。主要会使用到下面两个函数，
      BuildPipeline.PushAssetDependencies()：依赖资源压栈；


　　BuildPipeline.PopAssetDependencies()：依赖资源出栈。


      笔者将上表面的Texture3.prefab复制了两份，改为Texture1.prefab 和 Texture2.prefab。还准备好预制的图片

下面是我的打包函数:

[MenuItem("Assets/Build Rely AssetBundle")]        static public void ExportRelyAssetBundle() {            string filePath = Application.streamingAssetsPath+"/";            if (filePath.Length <= 0) {                return;            }            BuildAssetBundleOptions buildOp = BuildAssetBundleOptions.CollectDependencies | BuildAssetBundleOptions.CompleteAssets            | BuildAssetBundleOptions.DeterministicAssetBundle;            BuildPipeline.PushAssetDependencies();                Object shared = AssetDatabase.LoadMainAssetAtPath("Assets/Textures/rainDrop.png");                BuildPipeline.BuildAssetBundle(shared, null, filePath + shared.name + ".unity3d", buildOp, BuildTarget.StandaloneWindows);                BuildPipeline.PushAssetDependencies();                    Object tex1 = AssetDatabase.LoadMainAssetAtPath("Assets/Textures/Texture1.prefab");                    BuildPipeline.BuildAssetBundle(tex1, null, filePath + tex1.name + ".unity3d", buildOp, BuildTarget.StandaloneWindows);                BuildPipeline.PopAssetDependencies();                BuildPipeline.PushAssetDependencies();                    Object tex2 = AssetDatabase.LoadMainAssetAtPath("Assets/Textures/Texture2.prefab");                    BuildPipeline.BuildAssetBundle(tex2, null, filePath + tex2.name + ".unity3d", buildOp, BuildTarget.StandaloneWindows);                BuildPipeline.PopAssetDependencies();                            BuildPipeline.PopAssetDependencies();            EditorUtility.DisplayDialog("", "Build Completed", "OK");            AssetDatabase.Refresh();        }

AssetBundle依赖资源\共享资源加载

public string[] textureName;    public string picName;// Use this for initializationvoid Start () {        if (picName.Length > 0)        {            StartCoroutine(LoadAssetTexture(PlatflamPath() + picName + ".unity3d", picName));        }        for (int i = 0; i < textureName.Length; i++)        {            StartCoroutine(LoadAssetBundle(PlatflamPath() + textureName[i] + ".unity3d", textureName[i]));        }        }      static public IEnumerator LoadAssetBundle(string filepath,string assetName) {         WWW www = new WWW(filepath);        yield return www;        if (www == null) {            Debug.Log(" www is null ");        }        else if (www.error != null) {            Debug.Log("error " + www.error);        }        else if (www.isDone) {            AssetBundle assetBundle = www.assetBundle;            AssetBundleRequest requet = assetBundle.LoadAsync(assetName, typeof(GameObject));            yield return requet;            if (requet.isDone) {                GameObject obj = Instantiate(requet.asset) as GameObject;                }                    }        www.Dispose();        www = null;    }    static public string PlatflamPath()    {        return string.Format("file://{0}", Application.streamingAssetsPath) + "/";    }    static public IEnumerator LoadAssetTexture(string filepath, string assetName)    {        WWW www = new WWW(filepath);        yield return www;        if (www == null)        {            Debug.Log(" www is null ");        }        else if (www.error != null)        {            Debug.Log("error " + www.error);        }        else if (www.isDone)        {            AssetBundle assetBundle = www.assetBundle;        }        www.Dispose();        www = null;    }

注意事项：

加载的时候需要加载图片，再加载跟它有关联的对象，笔者试过先加载后者，图片资源会丢失。
       另外，Push和Pos都是成对使用。

相比之下，后者打包的方式前者节省空间。具体使用情况还是视个人情况而定。
     
    吐槽一下，第一次写博客，没想到写个博客都这么麻烦，写博客确实不是那么的简单。刚看了一下草稿，我了勒个去，排版简直不能看，还是默默的排版去。

参考博客 ：AssetBundle系列——共享资源打包/依赖资源打包

                    Unity手游之路<十一>资源打包Assetbundle