unity3d加密資源並緩存加載

unity3d加密資源並緩存加載

轉自：http://www.haogongju.net/art/1931680

首先要鄙視下unity3d的文檔編寫人員極度不負責任，到發帖爲止依然沒有更新正確的示例代碼。

// C# Example

// Builds an asset bundle from the selected objects in the project view.

// Once compiled go to "Menu" -> "Assets" and select one of the choices

// to build the Asset Bundle

using UnityEngine;

using UnityEditor;

using System.IO;

public class ExportAssetBundles {

[MenuItem("Assets/Build AssetBundle Binary file From Selection - Track dependencies ")]

static void ExportResource () {

// Bring up save panel

string path = EditorUtility.SaveFilePanel ("Save Resource", "", "New Resource", "unity3d");

if (path.Length != 0) {

// Build the resource file from the active selection.

Object[] selection = Selection.GetFiltered(typeof(Object), SelectionMode.DeepAssets);

BuildPipeline.BuildAssetBundle(Selection.activeObject, selection, path, BuildAssetBundleOptions.CollectDependencies | BuildAssetBundleOptions.CompleteAssets);

Selection.objects = selection;

FileStream fs = new FileStream(path,FileMode.Open,FileAccess.ReadWrite);

byte[] buff = new byte[fs.Length+1];

fs.Read(buff,0,(int)fs.Length);

buff[buff.Length-1] = 0;

fs.Close();

File.Delete(path);

string BinPath = path.Substring(0,path.LastIndexOf('.'))+".bytes";

//              FileStream cfs = new FileStream(BinPath,FileMode.Create);

cfs.Write(buff,0,buff.Length);

buff =null;

cfs.Close();

//              string AssetsPath = BinPath.Substring(BinPath.IndexOf("Assets"));

//              Object ta = AssetDatabase.LoadAssetAtPath(AssetsPath,typeof(Object));

//              BuildPipeline.BuildAssetBundle(ta, null, path);

}

}

[MenuItem("Assets/Build AssetBundle From Selection - No dependency tracking")]

static void ExportResourceNoTrack () {

// Bring up save panel

string path = EditorUtility.SaveFilePanel ("Save Resource", "", "New Resource", "unity3d");

if (path.Length != 0) {

// Build the resource file from the active selection.

BuildPipeline.BuildAssetBundle(Selection.activeObject, Selection.objects, path);

}

}

}

　　把打包的文件轉換成了binary文件並多加了一個字節加密。

　　當bytes文件生成好後再選中它，使用"Assets/Build AssetBundle From Selection - No dependency tracking"再次打包。

using UnityEngine; 

using System.Collections; 

using System; 

public class WWWLoadTest : MonoBehaviour 

{

public string BundleURL; 

public string AssetName; 

IEnumerator Start() 

{

 	cWWW www =WWW.LoadFromCacheOrDownload(BundleURL,2);

	yield return www; 

	TextAsset txt = www.assetBundle.Load("characters",typeof(TextAsset)) as TextAsset; 

	byte[] data = txt.bytes; byte[] decryptedData = Decryption(data); 

	Debug.LogError("decryptedData length:"+decryptedData.Length); 

	StartCoroutine(LoadBundle(decryptedData)); 

} 

IEnumerator LoadBundle(byte[] decryptedData)

{ 

	AssetBundleCreateRequest acr = AssetBundle.CreateFromMemory(decryptedData); 

	yield return acr; 

	AssetBundle bundle = acr.assetBundle; Instantiate(bundle.Load(AssetName)); 

} 

byte[] Decryption(byte[] data)

{ 

	byte[] tmp = new byte[data.Length-1];

	for(int i=0;i<data.Length-1;i++)

	{ 

		tmp[i] = data[i]; 

	} 

	return tmp; 

} 

}

 

WWW.LoadFromCacheOrDownload的作用就是下載並緩存資源，要注意後面的版本號參數，如果替換了資源卻沒有更新版本號，客戶端依然會加載緩存中的文件。

www.assetBundle.Load("characters",typeof(TextAsset)) as TextAsset  //characters是加密文件的名字

AssetBundleCreateRequest acr = AssetBundle.CreateFromMemory(decryptedData);           

這句是官網最坑爹的，AssetBundle.CreateFromMemory明明返回的是AssetBundleCreateRequest官網卻寫得是AssetBundle，而且AssetBundleCreateRequest是一個異步加載，必須用協程的方式加載官網也沒有提到。跟多兄弟就倒在了這裏

完。