Unity AssetBundle笔记

 学习资源 https://www.bilibili.com/video/BV1Et411Z76x?p=11

AssetBundles打包

需要打包的两个资源，一个prefab、一个material，prefab引用了material

两个功能，删除AssetBundles文件夹，和不删除AssetBundles里面的东西进行打包，打包两次则会有两倍同样东西

/*
 * Author : 
 * Time   : 2020.5
 * Title  : 
 * Description:
 * 
 * 
 */
using System.IO;
using UnityEditor;
using UnityEngine;
static class BuildAssetBundles
{
    /// <summary>
    /// 在AssetBundles（和Asset同级）下创建所有ab包
    /// </summary>
    [MenuItem("Assets/Build AssetBundles(Dont Delete Exist AssetBundles)")]
    static void Build()
    {
        if (!Directory.Exists("AssetBundles"))
            Directory.CreateDirectory("AssetBundles");

        BuildPipeline.BuildAssetBundles("AssetBundles", 
            BuildAssetBundleOptions.ChunkBasedCompression, BuildTarget.StandaloneWindows64);
    }
    /// <summary>
    /// 删除AssetBundles文件下的所有东西（包括该文件夹）
    /// </summary>
    [MenuItem("Assets/Delete All AssetBundles")]
    static void DeleteAll()
    {
        Delete("AssetBundles");
    }
    /// <summary>
    /// 删除路径下的所有文件夹，包括该文件夹
    /// </summary>
    /// <param name="path"></param>
    static void Delete(string path)
    {
        DirectoryInfo dir = new DirectoryInfo(path);
        FileSystemInfo[] files = dir.GetFileSystemInfos();

        //因为是文件信息集合不是文件集合所以可以用foreach迭代
        foreach (var file in files)
        {
            if (file is DirectoryInfo)
                Delete(file.FullName);
            else
                file.Delete();
        }
        dir.Delete();

    }

    
}

打包后的AssetBundles

可以看到wall包很小，这是因为Cube引用的material也被打包，如果只打包cube，两个cube就有两份material的大小

方法后两个参数分别为，打包压缩方式，打包平台

UnityWebRequest加载本地、服务器AssetBundles

UnityWebRequest加载本地、服务器资源。服务器用的是Tomcat，在Tomcat文件夹的webapp中创建了Unity文件夹，把上面上面上面代码生成的AssetBundles文件夹copy过去

wall依赖于material

如果不加载（GetContent）依赖包中的资源，则无法正常显示material，跟加载顺序无关。

/*
 * Author : 
 * Time   : 2020.5
 * Title  : 
 * Description:
 * 
 * 
 */
using System.Collections;
using UnityEngine;
using UnityEngine.Networking;

public class Example : MonoBehaviour
{
    private void Start()
    {
        //AssetBundle wallAB = AssetBundle.LoadFromFile("AssetBundles/wall.unity3d");
        //AssetBundle materialAB = AssetBundle.LoadFromFile("AssetBundles/material.unity3d");

        //GameObject prefab = wallAB.LoadAsset<GameObject>("Cube");
        //Instantiate(prefab);
        print(Application.dataPath);
        string path = @"D:/Documents/Unity/Project/TestProject/AssetBundles/";
        string url = "localhost:8080/Unity/AssetBundles/";
        StartCoroutine(LoadCoroutine(url));
    }

    IEnumerator LoadCoroutine(string path)
    {
        print("begin");
        UnityWebRequest wallRequest = UnityWebRequestAssetBundle.GetAssetBundle(path + "wall.unity3d");
        UnityWebRequest shareRequest = UnityWebRequestAssetBundle.GetAssetBundle(path + "material.unity3d");
        wallRequest.timeout = 10;
        shareRequest.timeout = 10;

        yield return wallRequest.SendWebRequest();
        print("down1");
        yield return shareRequest.SendWebRequest();
        print("down2");

        //如果不获取依赖包，则无法正常加载
        DownloadHandlerAssetBundle.GetContent(shareRequest);
        AssetBundle wallAB = DownloadHandlerAssetBundle.GetContent(wallRequest);

        GameObject wallPrefab = wallAB.LoadAsset<GameObject>("Cube");
        Instantiate(wallPrefab);
    }

}

这么写也是可以的，先实例化在加载material，材质在两秒后再加载出来

获取manifest，得到ab包依赖信息

    void LoadLocally()
    {
        AssetBundle wallAB = AssetBundle.LoadFromFile(@"AssetBundles/wall.unity3d");
        AssetBundle mainAB = AssetBundle.LoadFromFile(@"AssetBundles/AssetBundles");
        AssetBundleManifest manifest = mainAB.LoadAsset<AssetBundleManifest>("AssetBundleManifest");

        string[] wallABDependencies = manifest.GetAllDependencies("wall.unity3d");
        foreach (var s in wallABDependencies)
        {
            AssetBundle.LoadFromFile(@"AssetBundles/" + s);
        }

        GameObject prefab = wallAB.LoadAsset<GameObject>("Cube");
        Instantiate(prefab);
    }

不用知道Cube所需要Material的ab名字就能加载了

上面的mainAB和manifest的名字是确定的