diff --git a/examples/print.php b/examples/print.php
index e8e9fd1..2153645 100644
--- a/examples/print.php
+++ b/examples/print.php
@@ -5,15 +5,18 @@ namespace Blobt\Luxcore\scene;
 include dirname(dirname(__FILE__)) . "/vendor/autoload.php";
 
 
-$renderEngineType = new RenderEngine();
-echo $renderEngineType;
 
+//设置打印渲染引擎的配置参数
+$renderEngine = new RenderEngine();
+echo $renderEngine;
+
+//设置打印GPU渲染设备的配置参数
 $openCL = new OpenCL();
 echo $openCL;
 
-$cpuThreadsCount = new Native(['threadsCount' => 64]);
-
-echo $cpuThreadsCount;
+//设置打印GPU渲染设备的配置参数
+$native = new Native(['threadsCount' => 64]);
+echo $native;
 
 
 ?>
diff --git a/src/scene/Native.php b/src/scene/Native.php
index 1e7aae9..9140400 100644
--- a/src/scene/Native.php
+++ b/src/scene/Native.php
@@ -6,17 +6,8 @@ class Native extends BaseCfg
 {
     
     /**
-     * @var integer //使用多少线程数
+     * @var integer //使用多少线程数（取值范围： 1 >= $threadsCount ）
      */
-    protected $threadsCount = 4;
-
-    /**
-     * 在CPU渲染模式下，设置使用多少线程数
-     * @var integer $setThreadsCount 传入一个控制使用多少CPU线程数的整数
-     */
-    public function setThreadsCount($count)
-    {
-        $this->threadsCount = $count;
-    }
-
+    public $threadsCount = 4;
+    
 }
diff --git a/src/scene/OpenCL.php b/src/scene/OpenCL.php
index e199ba7..212652f 100644
--- a/src/scene/OpenCL.php
+++ b/src/scene/OpenCL.php
@@ -13,22 +13,22 @@ class OpenCL extends BaseCfg
     /**
      * @var integral 是否使用cpu渲染，默认是
      */
-    protected $cpuUse = self::CLOSE;
+    public $cpuUse = self::CLOSE;
 
     /**
      * @var integral 是否使用gpu渲染，默认否
      */
-    protected $gpuUse = self::OPEN;
+    public $gpuUse = self::OPEN;
 
     /**
-     * @var string 在GPU渲染模式下，使用哪些GPU设备
+     * @var string 控制使用哪些GPU设备的字符串（取值：是一段能标识系统中一个或多个GPU设备的ID字符串）
      */
-    protected $devicesSelect = '10';
+    public $devicesSelect = '10';
     
     /**
-     * @var integral 在GPU渲染模式下，CPU是否渲染，并以多少线程渲染
+     * @var integral GPU渲染模式下，设置CPU是否渲染和多少线程渲染（取值范围： 0 >= $threadsCount ）
      */
-    protected $nativeThreadsCount = 4;
+    public $nativeThreadsCount = 4;
 
 
     /**
@@ -50,22 +50,4 @@ class OpenCL extends BaseCfg
     }
 
 
-    /**
-     * 在GPU渲染模式下，设置使用哪些GPU设备
-     * @var string $gpuIdStr 传入一个控制使用哪些GPU设备的字符串
-     */
-    public function selectDevices($gpuIdStr)
-    {
-        $this->devicesSelect = $gpuIdStr;
-    }
-
-    /**
-     * 在GPU渲染模式下，设置CPU是否渲染，并以多少线程渲染
-     * @var integer $nativeThreadsCount 传入一个控制CPU是否渲染，并以多少线程渲染的整数
-     */
-    public function setNativeThreadsCount($count)
-    {
-        $this->nativeThreadsCount = $count;
-    }
-
 }
diff --git a/src/scene/Path.php b/src/scene/Path.php
index 8dd2ae5..a6bce24 100644
--- a/src/scene/Path.php
+++ b/src/scene/Path.php
@@ -4,6 +4,14 @@ namespace Blobt\Luxcore\scene;
 
 class Path extends BaseCfg
 {
-    public $pathdepth = null;
-
+    /**
+     * @var integer 光线追踪的最的深度
+     */
+    public $pathdepthTotal = 7;
+    public $pathdepthDiffuse = 5;
+    public $pathdepthGlossy = 5;
+    public $pathdepthSpecular = 6;
+    public $hybridbackforwardEnable = 0;
+    public $hybridbackforwardPartition = 0;
+    public $hybridbackforwardGlossinessthreshold = 0.049;
 }
diff --git a/src/scene/RenderEngine.php b/src/scene/RenderEngine.php
index 54892b6..5a49732 100644
--- a/src/scene/RenderEngine.php
+++ b/src/scene/RenderEngine.php
@@ -4,19 +4,15 @@ namespace Blobt\Luxcore\scene;
 
 class RenderEngine extends BaseCfg
 {
-        
-    /**
-     * @var string 使用何种渲染引擎
-     */
-    private $type = 'PATHOCL';
+    
+    const TYPE_PATHCPU = 'PATHCPU';
+    const TYPE_PATHGPU = 'PATHGPU';
+    const TYPE_BIDIRCPU = 'BIDIRCPU';
+
 
     /**
-     * 设置渲染引擎类型
-     * @var string $engineStr 传入一个表示渲染引擎类型的字符串
+     * @var string 使用何种渲染引擎(可取值是 PATHCPU、PATHGPU、BIDIRCPU 三个字符串之一)
      */
-    public function setRenderEngineType($engineStr)
-    {
-        $this->type = $engineStr;
-    }
+    public $type = self::TYPE_PATHGPU;
 
 }