AssetBundle资源打包
1.AssetLabels资源标签
文件名:资源打包成AssetBundle后的文件名,类似于压缩包的名字
后缀:自定义
文件名和后缀名都是小写格式(大写会自动转为小写)
2. BuildPipeline.BuildAssetBundles(string outputPath, BuildAssetBundleOptions assetBundleOptions, BuildTarget targetPlatform) 打包所有设置了AssetLabel的资源
outputPath:路径,打包出来的AssetBunlde文件存放的位置
BuildAssetBundleOptions:选项,设置AssetBundle打包过程中压缩方式
BuildAssetBundleOptions枚举选项:
None使用LZMA压缩算法进行压缩,打包后资源体积最小
UncompressedAssetBundle不压缩,打包后的AssetBundle体积最大,但是加载速度最快
ChunkBasedCompression使用LZ4压缩算法进行压缩,打包后的AssetBundle体积和加载速度介于上面二者之间
BuildTarget:平台,AssetBundle是平台之间不兼容的,IOS,Android是两套资源
在AssetLabels区域填写AssetBundle名称的时候,名称是可以分目录嵌套的:文件夹名/文件名
AssetBundle打包后的资源包,分两部分组成:
1.资源打包出来的AssetBundle文件
2.AssetBundle文件配套的manifest文本文件
manifest文件
manifest文件用于专门存储打包后的AssetBundle文件的基本信息,主要包含:
**CRC校验码:**类似于MD5,用于计算出该资源的一个特殊信息标示
**ClassTypes列表:**当前资源关联使用到了Unity中的哪些类,这些类是以编号索引的形式存在的,每个编号都对应一个类文件
**Assets:**AssetsBundle里包含了哪些资源文件
**Dependencies:**依赖
在打包出来的AssetBundle文件中,有一个特殊的manifest文件,和AssetBundle存放的文件夹同名,且只在根文件夹下有唯一的一个
这个manifest文件可以称作"AssetBundle目录文件",它存储了打包出来的所有AssetBundle的文件的索引信息
通过这个目录文件,可以找到所有的AssetBundle文件
AssetBundle资源加载
将项目资源打包成AssetBundle后,一般有两种操作
一.将这些AssetBundle留着项目工程中,当成普通资源使用
1.加载AssetBundle资源到内存****
****AssetBundle ab = *AssetBundle.*LoadFromFile("路径");加载AssetBundle资源到内存,返回一个AssetBundle对象**
*2.从AssetBundle中获取资源*****
T res = ab.LoadAsset
3.实例化
打包
[MenuItem("xx/xxx")]
public static void Build_WINDOWS64()
{
string outputPath = Path.Combine(Application.streamingAssetsPath, "Data");
if (!Directory.Exists(outputPath))
Directory.CreateDirectory(outputPath);
BuildPipeline.BuildAssetBundles(outputPath, BuildAssetBundleOptions.None, BuildTarget.StandaloneWindows64);//自己选择平台
AssetDatabase.Refresh();
}
加载
using System.Collections;
using System.Collections.Generic;
public class AssetBundleManager
{
private readonly string _path = UnityEngine.Application.streamingAssetsPath + "/Data/";
private static AssetBundleManager _instance;
private bool mIsLoadingEnd = false;
public bool IsLoadingEnd { get { return mIsLoadingEnd; } }
private List<string> mLoadingNames;
private Dictionary<string, UnityEngine.Object> mAssets;
private Dictionary<string, UnityEngine.Texture2D> mTexture2Ds;
public static AssetBundleManager GetInstance()
{
if (_instance == null)
{
_instance = new AssetBundleManager();
}
return _instance;
}
private AssetBundleManager()
{
mLoadingNames = new List<string>(){
//todo:要加载的资源名
};
mAssets = new Dictionary<string, UnityEngine.Object>();
mTexture2Ds = new Dictionary<string, UnityEngine.Texture2D>();
}
/// <summary>
/// 加载assetsbundle /// 记得先加载到内存StartCoroutine(AssetBundleManager.GetInstance().Loading());
/// </summary>
public IEnumerator Loading()
{
foreach (var nameAndType in mLoadingNames)
{
string filename = _path + nameAndType.ToLower();
UnityEngine.AssetBundleCreateRequest request = UnityEngine.AssetBundle.LoadFromFileAsync(filename);
yield return request;
LoadAsset(request.assetBundle);
}
mIsLoadingEnd = true;
}
private UnityEngine.AssetBundle LoadAssetBundle(string fileName)
{
UnityEngine.AssetBundle AB = UnityEngine.AssetBundle.LoadFromFile(_path + fileName);
return AB;
}
private void LoadAsset(UnityEngine.AssetBundle ab)
{
UnityEngine.Object[] assets = ab.LoadAllAssets();
for (int i = 0; i < assets.Length; i++)
{
//一张图片的AssetsBundle包含自身Texture2D和它里面全部Sprite,有可能重名
if (!typeof(UnityEngine.Texture2D).Equals(assets[i].GetType()))
mAssets.Add(assets[i].name, assets[i]);
else
mTexture2Ds.Add(assets[i].name, assets[i] as UnityEngine.Texture2D);
}
}
/// <summary>
/// 从assetbundle获取texture2d
/// </summary>
public UnityEngine.Texture2D GetTexture2D(string name)
{
UnityEngine.Texture2D obj;
mTexture2Ds.TryGetValue(name, out obj);
return obj;
}
/// <summary>
/// 从assetbundle获取Object
/// </summary>
public UnityEngine.Object GetAsset(string name)
{
UnityEngine.Object obj;
mAssets.TryGetValue(name, out obj);
return obj;
}
}
二.将这些AssetBundle上传服务器,客户端第一次运行时从服务器下载AssetBundle缓存到本地再使用(实现客户端的安装包与资源分离,降低客户端安装包的体积)****
1.服务器端下载主文件
从服务器端下载AssetBundle需要web路径地址,每一个地址对应一个AssetBundle文件.我们不可能在代码中写几十上百个文件的web地址,所以我们需要先下载"目录AssetBundle文件",然后通过它来间接获取其他AssetBundle文件的下载路径地址.
需要引入命名空间using UnityEngine.Networking;
using System.Collections;
using System.IO;
using UnityEngine;
using UnityEngine.Networking;
public class TestAssetBundle : MonoBehaviour
{
private string mainAssetBundleURL = @"http://www.xxx.com.xxx/AssetBundleFile";
private string allAssetBundleURL = @"http://www.xxx.com.xxx/";
void Start()
{
StartCoroutine(DownloadMainAssetBundle());
}
/// <summary>
/// 下载目录AssetBundle文件
/// </summary>
IEnumerator DownloadMainAssetBundle()
{
//创建一个获取AssetBundle文件的web请求
UnityWebRequest request = UnityWebRequestAssetBundle.GetAssetBundle(mainAssetBundleURL);
//发送web请求
yield return request.SendWebRequest();
//从请求中获取内容,返回AssetBundle类型的数据
AssetBundle ab = DownloadHandlerAssetBundle.GetContent(request);
//从"目录AssetBundle"中获取manifest数据
AssetBundleManifest manifest = ab.LoadAsset<AssetBundleManifest>("AssetBundleManifest");
//获取manifest文件中所有的AssetBundle的名称信息
string[] names = manifest.GetAllAssetBundles();
foreach (var name in names)
{
StartCoroutine(DownloadAssetBundleAndSave(allAssetBundleURL + name));
}
}
/// <summary>
/// 下载AssetBundle并保存到本地
/// </summary>
IEnumerator DownloadAssetBundleAndSave(string url)
{
UnityWebRequest request = UnityWebRequest.Get(url);
yield return request.SendWebRequest();
// 截取路径地址中的文件名(需要引入System.IO)
string fileName = Path.GetFileName(url);
SaveAssetBundle(fileName, request.downloadHandler.data);
}
/// <summary>
/// 存储AssetBundle为本地文件
/// </summary>
private void SaveAssetBundle(string fileName, byte[] bytes)
{
//创建一个文件信息对象(System.IO)
FileInfo fileInfo = new FileInfo(Application.streamingAssetsPath + "//" + fileName);
//创建一个文件流对象
FileStream fs = fileInfo.Create();
//通过文件流对象,往文件内写入信息
fs.Write(bytes, 0, bytes.Length);
//文件写入存储到硬盘
fs.Flush();
//关闭文件流对象
fs.Close();
//销毁文件对象
fs.Dispose();
}
}