diff --git a/CMakeLists.txt b/CMakeLists.txt
index d18cf190b..aecff8275 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -147,6 +147,10 @@ endif()
 # bullet engine
 option(BUILD_BULLET_PHYSIC_LIB "Build bullet physic" ON)
 
+if (BUILD_RECAST_NAVIGATION_LIB)
+	add_definitions(-DUSE_BULLET_PHYSIC_ENGINE)
+endif()
+
 # skylicht recast navigation
 option(BUILD_RECAST_NAVIGATION_LIB "Build Recast Navigation" ON)
 
diff --git a/Projects/Skylicht/Physics/CMakeLists.txt b/Projects/Skylicht/Physics/CMakeLists.txt
index 61ec88755..21c1d9d2e 100644
--- a/Projects/Skylicht/Physics/CMakeLists.txt
+++ b/Projects/Skylicht/Physics/CMakeLists.txt
@@ -6,8 +6,13 @@ include_directories(
 	${SKYLICHT_ENGINE_SOURCE_DIR}/Projects/Skylicht/System/Source
 	${SKYLICHT_ENGINE_SOURCE_DIR}/Projects/Skylicht/Audio/Source
 	${SKYLICHT_ENGINE_SOURCE_DIR}/Projects/Skylicht/Engine/Source
+	${SKYLICHT_ENGINE_SOURCE_DIR}/Projects/Bullet3/src
 )
 
+if (BUILD_BULLET_PHYSIC_LIB)
+include_directories(${SKYLICHT_ENGINE_SOURCE_DIR}/Projects/Bullet3/src)
+endif()
+
 file(GLOB_RECURSE skylicht_physics 
 	./Source/*.cpp 
 	./Source/*.hpp 
@@ -29,4 +34,13 @@ elseif(MSVC)
 target_link_libraries(Physics Engine System)
 elseif(CYGWIN OR MINGW)
 target_link_libraries(Physics Engine System)
+endif()
+
+if (BUILD_BULLET_PHYSIC_LIB)
+target_link_libraries(Physics BulletInverseDynamics BulletSoftBody BulletCollision BulletDynamics LinearMath Bullet3Common)
+
+IF(BUILD_BULLET3)
+target_link_libraries(Physics Bullet3OpenCL Bullet2FileLoader Bullet3Dynamics Bullet3Collision Bullet3Geometry )
+ENDIF(BUILD_BULLET3)
+
 endif()
\ No newline at end of file
diff --git a/Projects/Skylicht/Physics/Source/Bullet/CBulletUtils.h b/Projects/Skylicht/Physics/Source/Bullet/CBulletUtils.h
new file mode 100644
index 000000000..099364987
--- /dev/null
+++ b/Projects/Skylicht/Physics/Source/Bullet/CBulletUtils.h
@@ -0,0 +1,101 @@
+#pragma once
+
+#include "pch.h"
+
+#ifdef USE_BULLET_PHYSIC_ENGINE
+
+#include <btBulletCollisionCommon.h>
+#include <btBulletDynamicsCommon.h>
+
+namespace Bullet
+{
+	inline static btVector3 irrVectorToBulletVector(const core::vector3df& toConvert)
+	{
+		return btVector3(toConvert.X, toConvert.Y, toConvert.Z);
+	}
+
+	inline static core::vector3df bulletVectorToIrrVector(const btVector3& toConvert)
+	{
+		return core::vector3df(toConvert.x(), toConvert.y(), toConvert.z());
+	}
+
+	inline static void quaternionToEuler(const btQuaternion& TQuat, btVector3& TEuler)
+	{
+		btScalar W = TQuat.getW();
+		btScalar X = TQuat.getX();
+		btScalar Y = TQuat.getY();
+		btScalar Z = TQuat.getZ();
+		float WSquared = W * W;
+		float XSquared = X * X;
+		float YSquared = Y * Y;
+		float ZSquared = Z * Z;
+		TEuler.setX(atan2f(2.0f * (Y * Z + X * W), -XSquared - YSquared + ZSquared + WSquared));
+		TEuler.setY(asinf(-2.0f * (X * Z - Y * W)));
+		TEuler.setZ(atan2f(2.0f * (X * Y + Z * W), XSquared - YSquared - ZSquared + WSquared));
+		TEuler *= core::RADTODEG;
+	}
+
+	static core::vector3df quaternionToIrrEuler(const btQuaternion& TQuat)
+	{
+		btVector3 bulletEuler;
+		quaternionToEuler(TQuat, bulletEuler);
+		return Bullet::bulletVectorToIrrVector(bulletEuler);
+	}
+
+	inline static core::vector3df bulletTransformToIrrRotation(const btTransform& tr)
+	{
+		core::matrix4 mat;
+
+#ifdef BT_USE_NEON
+		float ptr[16] __attribute__((aligned(16)));
+		tr.getOpenGLMatrix(ptr);
+
+		float* m = mat.pointer();
+		for (int i = 0; i < 16; i++)
+		{
+			m[i] = (float)ptr[i];
+		}
+#else
+		f32* ptr;
+		ptr = mat.pointer();
+		tr.getOpenGLMatrix(ptr);
+#endif
+		return mat.getRotationDegrees();
+	}
+
+	inline static void bulletTransformToIrrMatrix(const btTransform& tr, core::matrix4& mat)
+	{
+#ifdef BT_USE_NEON
+		float ptr[16] __attribute__((aligned(16)));
+		tr.getOpenGLMatrix(ptr);
+
+		float* m = mat.pointer();
+		for (int i = 0; i < 16; i++)
+			m[i] = ptr[i];
+#else
+		f32* ptr;
+		ptr = mat.pointer();
+		tr.getOpenGLMatrix(ptr);
+#endif
+	}
+
+	inline static btTransform irrRotationToBulletTransform(const core::vector3df& rotation)
+	{
+		core::matrix4 mat;
+		mat.setRotationDegrees(rotation);
+		btTransform tr;
+		tr.setFromOpenGLMatrix(mat.pointer());
+
+		return tr;
+	}
+
+	inline static btTransform glMatrixToBulletTransform(float* matrix)
+	{
+		btTransform tr;
+		tr.setFromOpenGLMatrix(matrix);
+
+		return tr;
+	}
+}
+
+#endif
\ No newline at end of file