extract textures and meshes from asset bundles

AssetBundleExtract.cs

using UnityEngine;
using UnityEditor;
using System.IO;
using System.Xml;
using System.Collections;
using System.Collections.Generic;

public class AssetBundleExtract : MonoBehaviour {
	
	private string resdir = "~/Work/UnityProj/GameRes/Raw/";
	private string outputdir = "~/Work/UnityProj/Gameres/Output/";
	
	private string textureFolder = "Texture";
	private string meshFolder = "Mesh";
	
	private GameObject planeObj = null;
	private Transform planeTrans = null;
	private int planeWidth = 1024;
	private int planeHeight = 1024;

	// Use this for initialization
	void Start () {
		planeObj = GameObject.Find("Plane");
		planeTrans = planeObj.transform;
		StartCoroutine(LoadAssets());
	}
	
	private IEnumerator LoadAssets() {
		XmlDocument xmlDoc = new XmlDocument();
		xmlDoc.Load(resdir + "HashSourceList.xml");
		XmlNode rootNode = xmlDoc.SelectSingleNode("Root");
		
		XmlNodeList nodeList = rootNode.ChildNodes;
		foreach (XmlNode node in nodeList) {
			string name = node.Attributes["name"].Value;
			string folder = resdir + node.Attributes["path"].Value;
			yield return StartCoroutine(LoadAsset(name, folder));
		}
		
		Debug.Log("work finished!!!");
	}
	
	private IEnumerator LoadAsset(string assetName, string assetPath) {
		WWW download = new WWW ("file://" + assetPath);
		yield return download;
		
		if ( download.error != null ) {
            Debug.LogError( download.error );
            download.Dispose();
            yield break;
        }
        
        AssetBundle assetBundle = download.assetBundle;
        if (assetBundle == null) {
        	Debug.LogWarning("invalid asset bundle: " + assetName);
        	yield break;
        }
        
        Object[] assetList = assetBundle.LoadAll();
		foreach (Object o in assetList) {
			if (o.GetType() == typeof(Texture2D)) {
				Texture2D tex = o as Texture2D;
				yield return StartCoroutine(SaveTexture2D(tex));
			} else if (o.GetType() == typeof(Mesh)) {
				Mesh mesh = o as Mesh;
				yield return StartCoroutine(SaveMesh(mesh));
			} else if (o.GetType() == typeof(AnimationClip)) {
			} else if (o.GetType() == typeof(Material)) {
			} else if (o.GetType() == typeof(Avatar)) {
			} else if (o.GetType() == typeof(GameObject)) {
			} else if (o.GetType() == typeof(MonoScript)) {
			} else if (o.GetType() == typeof(Transform)) {
			} else if (o.GetType() == typeof(Shader)) {
			} else if (o.GetType() == typeof(AudioClip)) {
			} else if (o.GetType() == typeof(Sprite)) {
			} else if (o.GetType() == typeof(Animation)) {
			} else if (o.GetType() == typeof(Animator)) {
			} else if (o.GetType() == typeof(UnityEditorInternal.AnimatorController)) {
			} else if (o.GetType() == typeof(TextAsset)) {
			} else {
				Debug.LogError("asset type: " + o.GetType());
			}
		}
		
		assetBundle.Unload(true);
		download.Dispose();
		download = null;
	}
	
	private IEnumerator SaveTexture2D(Texture2D tex) {
		planeWidth = tex.width;
		planeHeight = tex.height;
		float scaleX = 1.0f;
		float scaleY = 1.0f;
		float posX = 0.0f;
		float posY = 1.0f;
		if (planeWidth == 1024) {
			scaleX = 1.0f;
			posX = 0.0f;
		} else if (planeWidth == 512) {
			scaleX = 0.5f;
			posX = 2.5f;
		} else if (planeWidth == 256) {
			scaleX = 0.25f;
			posX = 3.75f;
		} else if (planeWidth == 128) {
			scaleX = 0.125f;
			posX = 4.375f;
		} else if (planeWidth == 64) {
			scaleX = 0.0625f;
			posX = 4.40625f;
		} else if (planeWidth == 32) {
			scaleX = 0.03125f;
			posX = 4.421875f;
		} else {
			Debug.LogWarning("invalid texture width: " + planeWidth);
			yield break;
		}
		if (planeHeight == 1024) {
			scaleY = 1.0f;
			posY = 1.0f;
		} else if (planeHeight == 512) {
			scaleY = 0.5f;
			posY = -1.5f;
		} else if (planeHeight == 256) {
			scaleY = 0.25f;
			posY = -2.75f;
		} else if (planeHeight == 128) {
			scaleY = 0.125f;
			posY = -3.375f;
		} else if (planeHeight == 64) {
			scaleY = 0.0625f;
			posY = -3.40625f;
		} else if (planeHeight == 32) {
			scaleY = 0.03125f;
			posY = -3.421875f;
		} else {
			Debug.LogWarning("invalid texture height: " + planeHeight);
			yield break;
		}
		planeTrans.position = new Vector3(posX, posY, 0.0f);
		planeTrans.localScale = new Vector3(scaleX, 1.0f, scaleY);
		
		planeObj.renderer.material.mainTexture = tex;
		yield return new WaitForEndOfFrame();
		
		Texture2D screenTex = new Texture2D(planeWidth, planeHeight, TextureFormat.RGB24, false);
		screenTex.ReadPixels(new Rect(0, 0, planeWidth, planeHeight), 0, 0, false);
		screenTex.Apply();
		
		byte[] data = screenTex.EncodeToPNG();
		Destroy(screenTex);
		File.WriteAllBytes(outputdir + textureFolder + "/" + tex.name + ".png", data);
		
		yield return new WaitForEndOfFrame();
	}
	
	private IEnumerator SaveMesh(Mesh mesh) {
		MeshExporter.MeshToFile(mesh, outputdir + meshFolder + "/" + mesh.name + ".obj");
		yield return null;
	}
}