diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7d3e549..6b6a604 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -12,11 +12,19 @@ if(TARGET ${PROJECT_NAME})
   return()
 endif()
 
-set(QT_VERSION_MAJOR 5)
-find_package(Qt${QT_VERSION_MAJOR} COMPONENTS Core Test REQUIRED)
-
+find_package(QT NAMES Qt5 Qt6 COMPONENTS Core REQUIRED)
 include(submodules/QuasarAppLib/CMake/QuasarApp.cmake)
 
+if (NOT ${QT_VERSION_MAJOR} EQUAL 5)
+    message("The ${PROJECT_NAME} support only qt5. please rebuild this project with qt6")
+    initAll()
+    addDoc(${PROJECT_NAME} ${CMAKE_CURRENT_SOURCE_DIR}/doxygen.conf)
+
+    return()
+endif()
+
+find_package(Qt${QT_VERSION_MAJOR} COMPONENTS Core Test REQUIRED)
+
 if (DEFINED TARGET_PLATFORM_TOOLCHAIN)
     if (${TARGET_PLATFORM_TOOLCHAIN} STREQUAL "wasm32")
         initAll()
diff --git a/src/Core/Crawl/day.h b/src/Core/Crawl/day.h
index 6ac569b..a3e4a08 100644
--- a/src/Core/Crawl/day.h
+++ b/src/Core/Crawl/day.h
@@ -20,8 +20,32 @@ template <class Sun, class Moon>
 /**
  * @brief The Day class is template wrapper for the moon and sun objects.
  * The moon and sun objects moving around world center for imitation of the day.
+ *
+ * ### Integration on the world.
+ * You need to add one object of this class in the IWorld::initWorldRules method.
+ * **Example:**
+ *
+ * ```cpp
+ * CRAWL::WorldRule *World::initWorldRules() {
+
+    using Day = CRAWL::Day<CRAWL::Sun, CRAWL::Moon>;
+
+    return new CRAWL::WorldRule {
+        {0, {
+                {registerObject<Day>(), 1},
+            }
+        },
+        {1000, {
+                {registerObject<Day>(), 1},
+            }
+        },
+    };
+}
+ * ```
  * @note All objects will be moving around this objects with radius. The Radius by default is 2000.
  * @note This class automaticly sets ligth force for the light objects.
+ *
+ *
  */
 class Day: public IWorldItem, public Claster
 {
diff --git a/src/Core/Crawl/defaultlight.h b/src/Core/Crawl/defaultlight.h
index 4764537..50c14e2 100644
--- a/src/Core/Crawl/defaultlight.h
+++ b/src/Core/Crawl/defaultlight.h
@@ -14,7 +14,9 @@
 namespace CRAWL {
 
 /**
- * @brief The DefaultLight class This is default implementation of the wirld light.
+ * @brief The DefaultLight class This is default implementation of the world light.
+ * This object create uniform illumination for all world.
+ * For integration This object yo worl see the IWorld::initWorldRules method
  */
 class DefaultLight final:  public IWorldLight
 {
diff --git a/src/Core/Crawl/iworldlight.h b/src/Core/Crawl/iworldlight.h
index 74d33c5..50dac42 100644
--- a/src/Core/Crawl/iworldlight.h
+++ b/src/Core/Crawl/iworldlight.h
@@ -18,6 +18,28 @@ namespace CRAWL {
  * You need to create own qml file with light.
  *
  * @note If you wnat to create a new qml file the you need to inherit from the Light.qml file.
+ *
+ * ### Integration on the world.
+ * You need to add one object of this class in the IWorld::initWorldRules method.
+ * **Example:**
+ *
+ * ```cpp
+ * CRAWL::WorldRule *World::initWorldRules() {
+
+    return new CRAWL::WorldRule {
+        {0, {
+                {registerObject<MyLightObject>(), 1},
+            }
+        },
+        {1000, {
+                {registerObject<MyLightObject>(), 1},
+            }
+        },
+    };
+}
+ * ```
+ *
+ * For integration This object you world see the IWorld::initWorldRules method
  */
 class CRAWL_EXPORT IWorldLight: public ClasterItem
 {
@@ -30,6 +52,7 @@ class CRAWL_EXPORT IWorldLight: public ClasterItem
     Q_PROPERTY(float shadowBias READ shadowBias WRITE setShadowBias NOTIFY shadowBiasChanged)
 
 public:
+
     IWorldLight(const QString& name,
                 const QString& viewTempalte = "qrc:/CrawlModule/Light.qml",
                 QObject *ptr = nullptr);