diff --git a/Assets/_Scenes/MainManu.unity b/Assets/_Scenes/MainManu.unity
index b6eab13..599faa9 100644
Binary files a/Assets/_Scenes/MainManu.unity and b/Assets/_Scenes/MainManu.unity differ
diff --git a/Assets/_Scripts/Core/TerrainManager.cs b/Assets/_Scripts/Core/TerrainManager.cs
index fe9a3ee..d82ea9b 100644
--- a/Assets/_Scripts/Core/TerrainManager.cs
+++ b/Assets/_Scripts/Core/TerrainManager.cs
@@ -39,52 +39,57 @@ void Start()
 
     void StartChunkUpdateThread()
     {
-        thread = new Thread(new ThreadStart(delegate
+        thread = new Thread(new ThreadStart(ChunkUpdateWork));
+        thread.Priority = System.Threading.ThreadPriority.Lowest;
+        thread.Start();
+    }
+
+    void ChunkUpdateWork()
+    {
+        while (threadRunning)
         {
-            while (threadRunning)
+            Stopwatch.Reset();
+            Stopwatch.Start();
+            if (chunkQueue.TerrainCount != 0)
             {
-                Stopwatch.Reset();
-                Stopwatch.Start();
-                if (chunkQueue.TerrainCount != 0)
+                int count = chunkQueue.TerrainCount;
+                for (int i = 0; i < count; i++)
                 {
-                    int count = chunkQueue.TerrainCount;
-                    for (int i = 0; i < count; i++)
+                    int index = chunkQueue.PopTerrain();
+                    BlockTerrain.Chunk chunk = Terrain.GetChunk(index);
+                    if (chunk == null)
+                        continue;
+                    lock (chunk)
                     {
-                        int index = chunkQueue.PopTerrain();
-                        BlockTerrain.Chunk chunk = Terrain.GetChunk(index);
-                        lock (chunk)
+                        switch (Terrain.chunkStats.Get(index).state)
                         {
-                            switch (Terrain.chunkStats.Get(index).state)
-                            {
-                                case 3:
-                                    terrainGenerator.MeshFromChunk(chunk, out chunk.mesh[0]);
-                                    terrainGenerator.MeshFromTransparent(chunk, out chunk.mesh[2]);
-                                    break;
-                                case 1:
-                                    terrainGenerator.MeshFromChunk(chunk, out chunk.mesh[0]);
-                                    break;
-                                case 2:
-                                    terrainGenerator.MeshFromTransparent(chunk, out chunk.mesh[2]);
-                                    break;
-                            }
+                            case 3:
+                                terrainGenerator.MeshFromChunk(chunk, out chunk.mesh[0]);
+                                terrainGenerator.MeshFromTransparent(chunk, out chunk.mesh[2]);
+                                break;
+                            case 1:
+                                terrainGenerator.MeshFromChunk(chunk, out chunk.mesh[0]);
+                                break;
+                            case 2:
+                                terrainGenerator.MeshFromTransparent(chunk, out chunk.mesh[2]);
+                                break;
                         }
-                        chunkQueue.AddMain(index);
                     }
+                    chunkQueue.AddMain(index);
                 }
-                if (needTerrainUpdate)
-                {
-                    UpdateTerrain(centerChunk.X, centerChunk.Y);
+            }
+            if (needTerrainUpdate)
+            {
+                UpdateTerrain(centerChunk.X, centerChunk.Y);
 
-                    needTerrainUpdate = false;
-                }
-                if (Stopwatch.ElapsedMilliseconds < updateMili)
-                {
-                    Thread.Sleep(updateMili - (int)Stopwatch.ElapsedMilliseconds);
-                }
+                needTerrainUpdate = false;
             }
-            Debug.Log("chunk loading thread closed");
-        }));
-        thread.Start();
+            if (Stopwatch.ElapsedMilliseconds < updateMili)
+            {
+                Thread.Sleep(updateMili - (int)Stopwatch.ElapsedMilliseconds);
+            }
+        }
+        Debug.Log("chunk loading thread closed");
     }
 
     void OnDisable()
diff --git a/Assets/_Scripts/FPSDisplay.cs b/Assets/_Scripts/FPSDisplay.cs
index 911a9bd..4fc3edd 100644
--- a/Assets/_Scripts/FPSDisplay.cs
+++ b/Assets/_Scripts/FPSDisplay.cs
@@ -9,7 +9,6 @@ public class FPSDisplay : MonoBehaviour
 	void Update()
 	{
 		deltaTime += (Time.unscaledDeltaTime - deltaTime) * 0.1f;
-
 	}
 
 	void OnGUI()
@@ -24,7 +23,7 @@ void OnGUI()
 		style.normal.textColor = new Color (1.0f, 1.0f, 1.0f, 1.0f);
 		float msec = deltaTime * 1000.0f;
 		float fps = 1.0f / deltaTime;
-		string text = string.Format("{0:0.0} ms ({1:0.} fps)\ncurrent chunk: {2}\n按ESC键暂停", msec, fps, TerrainManager.CurrentChunk ());
+		string text = string.Format("{0:0.0} ms ({1:0.} fps)\ncurrent chunk: {2}\n按ESC键暂停\n按P键截图", msec, fps, TerrainManager.CurrentChunk ());
 		TerrainRaycast.RaycastResult? r = GetComponent<TerrainRaycast> ().LookingAt;
 		if (r.HasValue) {
             //text += string.Format ("\nlooking at {0}", BlocksData.GetBlock(BlockTerrain.GetContent(r.Value.BlockValue)).Name);
@@ -32,4 +31,4 @@ void OnGUI()
 		}
 		GUI.Label (rect, text, style);
 	}
-}
\ No newline at end of file
+}
diff --git a/README.md b/README.md
index dd8cb55..84498d7 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,7 @@ Fancy SurvivalCraft Editor, inspired by [SCFE-Unity](https://github.com/khohryak
 * ~English support~
 * ~Multi-thread chunk loading~
 * ~Load Project.xml~
-* Setting panel
+* ~Setting panel~
 * Create a selection of blocks
 * Fill a selection with certain block
 * Save and Load selections
diff --git a/README.zh-cn.md b/README.zh-cn.md
index 6df87a0..e3d1ceb 100644
--- a/README.zh-cn.md
+++ b/README.zh-cn.md
@@ -6,7 +6,7 @@ Fancy SurvivalCraft Editor，可以翻译成“很棒的生存战争存档编辑
 * ~英文版~
 * ~多线程区块加载~
 * ~加载Project.xml~
-* 设置界面
+* ~设置界面~
 * 创建选区
 * 填充选区
 * 保存，导入选区