Unity5 裡面， 當場景裡的物體儲存成Prefab之後，LightMap的資訊就會丟失。Fuck。。

所以最後就寫了個指令碼，把每個Render裡的lightmap紀錄下來，當prefab例項化之後，重新設定。

上程式碼。。

相關設定：

注意事項：檢查下是否勾選了 Static -> BatchingStatic ，如果勾選了，一定要去除勾選 ！！！！！！

using UnityEngine;  
using System.Collections;  
using System.Collections.Generic;
using UnityEngine.Rendering;

public class PrefabLightmapData : MonoBehaviour {

	//LightMap資訊
	[System.Serializable]  
	public struct RendererInfo  
	{  
		public Renderer     renderer;  
		public int          lightmapIndex;  
		public Vector4      lightmapOffsetScale;  
	}

	//場景中的Fog資訊
	[System.Serializable]  
	public struct FogInfo  
	{  
		public bool         fog;  
		public FogMode      fogMode;  
		public Color        fogColor;
		public float        fogStartDistance;
		public float        fogEndDistance;
		public float 		fogDensity;
	}


	public FogInfo fogInfo;
	public List<RendererInfo> m_RendererInfo; 
	public List<Texture2D> lightmapNear;
	public List<Texture2D> lightmapFar;
	public LightmapData[] lightmapData;
	public LightmapsMode lightmapsMode;

	//地形的LightMap資訊
	public Terrain terrain;
	public RendererInfo terrainRendererInfo;

	//設定光照資訊
	[ContextMenu("SetUp")]
	public void SetUp(){  
		lightmapData = new LightmapData[lightmapNear.Count > lightmapFar.Count ? lightmapNear.Count : lightmapFar.Count];
		for(int i = 0; i < lightmapData.Length; i ++){
			lightmapData[i]=new LightmapData();
			lightmapData[i].lightmapFar = i < lightmapFar.Count ? lightmapFar[i] : null;
			lightmapData[i].lightmapNear = i < lightmapNear.Count ? lightmapNear[i] : null;
		}
		LightmapSettings.lightmapsMode = lightmapsMode;
		LightmapSettings.lightmaps=lightmapData;
		LoadLightmap();
		RenderSettings.fog = fogInfo.fog;
		RenderSettings.fogMode = fogInfo.fogMode;
		RenderSettings.fogColor = fogInfo.fogColor;
		RenderSettings.fogStartDistance = fogInfo.fogStartDistance;
		RenderSettings.fogEndDistance = fogInfo.fogEndDistance;
		RenderSettings.fogDensity = fogInfo.fogDensity;
	}

	//儲存光照資訊
	[ContextMenu("SaveData")]
	public void SaveData(){  
		SaveLightmap ();
	}
	
	public void SaveLightmap()
	{  
		fogInfo = new FogInfo ();
		fogInfo.fog = RenderSettings.fog;
		fogInfo.fogMode = RenderSettings.fogMode;
		fogInfo.fogColor = RenderSettings.fogColor;
		fogInfo.fogStartDistance = RenderSettings.fogStartDistance;
		fogInfo.fogEndDistance = RenderSettings.fogEndDistance;

		lightmapNear = new List<Texture2D>();
		lightmapFar = new List<Texture2D>();
		for(int i = 0; i < LightmapSettings.lightmaps.Length; i ++){
			LightmapData data = LightmapSettings.lightmaps[i];
			if(data.lightmapNear != null){
				lightmapNear.Add(data.lightmapNear);
			}

			if(data.lightmapFar != null){
				lightmapFar.Add(data.lightmapFar);
			}
		}
		m_RendererInfo = new List<RendererInfo> ();
		var renderers = GetComponentsInChildren<MeshRenderer>();  
		foreach (MeshRenderer r in renderers) {  
			if (r.lightmapIndex != -1) {  
				RendererInfo info = new RendererInfo();  
				info.renderer = r;  
				info.lightmapOffsetScale = r.lightmapScaleOffset;  
				info.lightmapIndex = r.lightmapIndex;  
				m_RendererInfo.Add(info);  
			}  
		}

		terrain = GetComponentInChildren<Terrain> ();
		if (terrain != null) {
			terrainRendererInfo = new RendererInfo();
			terrainRendererInfo.lightmapOffsetScale = terrain.lightmapScaleOffset;  
			terrainRendererInfo.lightmapIndex = terrain.lightmapIndex;  
		}
		lightmapsMode = LightmapSettings.lightmapsMode;
	}  
	
	public void LoadLightmap()  
	{  
		if (m_RendererInfo.Count <= 0) return;  

		if (terrain != null) {
			terrain.lightmapScaleOffset = terrainRendererInfo.lightmapOffsetScale;
			terrain.lightmapIndex = terrainRendererInfo.lightmapIndex;
		}

		foreach (var item in m_RendererInfo) {  
			item.renderer.lightmapIndex = item.lightmapIndex;  
			item.renderer.lightmapScaleOffset = item.lightmapOffsetScale;  
		}  
	}
}
 

在執行時場景初始化完成之後。呼叫SetUp方法，即可掛載lightMap。

重點！！我遇上個問題，需要保持原來存在的渲染場景，assetbundle才的LightMap能正常。否則就不會有LightMap，希望誰來個提示。

如果把原來渲染lightmap的場景刪了，那麼在手機上就會載入不到。
我估摸著是因為assetbundle的時候，沒有把lightmap的貼圖打包進去，只儲存了引用的關係。
所以如果場景刪了，那麼lightmap的貼圖也丟了。

如有疑問，請回復哦～～