diff --git a/glm/core/type_mat2x2.hpp b/glm/core/type_mat2x2.hpp
index aade1ef4..d3543245 100644
--- a/glm/core/type_mat2x2.hpp
+++ b/glm/core/type_mat2x2.hpp
@@ -45,6 +45,7 @@ namespace glm
 			typedef std::size_t size_type;
 			typedef tvec2<T> col_type;
 			typedef tvec2<T> row_type;
+            GLM_FUNC_DECL size_type length() const;
 			static GLM_FUNC_DECL size_type col_size();
 			static GLM_FUNC_DECL size_type row_size();
 
diff --git a/glm/core/type_mat2x2.inl b/glm/core/type_mat2x2.inl
index 7a53a969..12d04840 100644
--- a/glm/core/type_mat2x2.inl
+++ b/glm/core/type_mat2x2.inl
@@ -10,6 +10,12 @@
 namespace glm{
 namespace detail
 {
+    template <typename T>
+    GLM_FUNC_QUALIFIER typename tmat2x2<T>::size_type tmat2x2<T>::length() const
+    {
+        return 2;
+    }
+
 	template <typename T>
 	GLM_FUNC_QUALIFIER typename tmat2x2<T>::size_type tmat2x2<T>::col_size()
 	{
diff --git a/glm/core/type_mat2x3.hpp b/glm/core/type_mat2x3.hpp
index ed87f9e2..45169a8e 100644
--- a/glm/core/type_mat2x3.hpp
+++ b/glm/core/type_mat2x3.hpp
@@ -45,6 +45,7 @@ namespace glm
 			typedef std::size_t size_type;
 			typedef tvec3<T> col_type;
 			typedef tvec2<T> row_type;
+            GLM_FUNC_DECL size_type length() const;
 			static GLM_FUNC_DECL size_type col_size();
 			static GLM_FUNC_DECL size_type row_size();
 
diff --git a/glm/core/type_mat2x3.inl b/glm/core/type_mat2x3.inl
index 83e8b2e3..77441fb0 100644
--- a/glm/core/type_mat2x3.inl
+++ b/glm/core/type_mat2x3.inl
@@ -10,6 +10,12 @@
 namespace glm{
 namespace detail
 {
+    template <typename T>
+    GLM_FUNC_QUALIFIER typename tmat2x3<T>::size_type tmat2x3<T>::length() const
+    {
+        return 2;
+    }
+
 	template <typename T>
 	GLM_FUNC_QUALIFIER typename tmat2x3<T>::size_type tmat2x3<T>::col_size()
 	{
diff --git a/glm/core/type_mat2x4.hpp b/glm/core/type_mat2x4.hpp
index a14cc033..229b9996 100644
--- a/glm/core/type_mat2x4.hpp
+++ b/glm/core/type_mat2x4.hpp
@@ -45,6 +45,7 @@ namespace glm
 			typedef std::size_t size_type;
 			typedef tvec4<T> col_type;
 			typedef tvec2<T> row_type;
+            GLM_FUNC_DECL size_type length() const;
 			static GLM_FUNC_DECL size_type col_size();
 			static GLM_FUNC_DECL size_type row_size();
 
diff --git a/glm/core/type_mat2x4.inl b/glm/core/type_mat2x4.inl
index b19193f6..4736805d 100644
--- a/glm/core/type_mat2x4.inl
+++ b/glm/core/type_mat2x4.inl
@@ -10,6 +10,12 @@
 namespace glm{
 namespace detail
 {
+    template <typename T>
+    GLM_FUNC_QUALIFIER typename tmat2x4<T>::size_type tmat2x4<T>::length() const
+    {
+        return 2;
+    }
+
 	template <typename T>
 	GLM_FUNC_QUALIFIER typename tmat2x4<T>::size_type tmat2x4<T>::col_size()
 	{
diff --git a/glm/core/type_mat3x2.hpp b/glm/core/type_mat3x2.hpp
index 3457b72f..2c61e5c7 100644
--- a/glm/core/type_mat3x2.hpp
+++ b/glm/core/type_mat3x2.hpp
@@ -45,6 +45,7 @@ namespace glm
 			typedef std::size_t size_type;
 			typedef tvec2<T> col_type;
 			typedef tvec3<T> row_type;
+            GLM_FUNC_DECL size_type length() const;
 			static GLM_FUNC_DECL size_type col_size();
 			static GLM_FUNC_DECL size_type row_size();
 
diff --git a/glm/core/type_mat3x2.inl b/glm/core/type_mat3x2.inl
index 5fddb4c1..ec95a3dc 100644
--- a/glm/core/type_mat3x2.inl
+++ b/glm/core/type_mat3x2.inl
@@ -10,6 +10,12 @@
 namespace glm{
 namespace detail
 {
+    template <typename T>
+    GLM_FUNC_QUALIFIER typename tmat3x2<T>::size_type tmat3x2<T>::length() const
+    {
+        return 2;
+    }
+
 	template <typename T>
 	GLM_FUNC_QUALIFIER typename tmat3x2<T>::size_type tmat3x2<T>::col_size()
 	{
diff --git a/glm/core/type_mat3x3.hpp b/glm/core/type_mat3x3.hpp
index bf18c167..7d534a93 100644
--- a/glm/core/type_mat3x3.hpp
+++ b/glm/core/type_mat3x3.hpp
@@ -45,6 +45,7 @@ namespace glm
 			typedef std::size_t size_type;
 			typedef tvec3<T> col_type;
 			typedef tvec3<T> row_type;
+            GLM_FUNC_DECL size_type length() const;
 			static GLM_FUNC_DECL size_type col_size();
 			static GLM_FUNC_DECL size_type row_size();
 
diff --git a/glm/core/type_mat3x3.inl b/glm/core/type_mat3x3.inl
index 667f2235..80a3e8ed 100644
--- a/glm/core/type_mat3x3.inl
+++ b/glm/core/type_mat3x3.inl
@@ -10,6 +10,12 @@
 namespace glm{
 namespace detail
 {
+    template <typename T>
+    GLM_FUNC_QUALIFIER typename tmat3x3<T>::size_type tmat3x3<T>::length() const
+    {
+        return 3;
+    }
+
 	template <typename T>
 	GLM_FUNC_QUALIFIER typename tmat3x3<T>::size_type tmat3x3<T>::col_size()
 	{
diff --git a/glm/core/type_mat3x4.hpp b/glm/core/type_mat3x4.hpp
index 1f84ec7b..fa96870f 100644
--- a/glm/core/type_mat3x4.hpp
+++ b/glm/core/type_mat3x4.hpp
@@ -45,6 +45,7 @@ namespace glm
 			typedef std::size_t size_type;
 			typedef tvec4<T> col_type;
 			typedef tvec3<T> row_type;
+            GLM_FUNC_DECL size_type length() const;
 			static GLM_FUNC_DECL size_type col_size();
 			static GLM_FUNC_DECL size_type row_size();
 
diff --git a/glm/core/type_mat3x4.inl b/glm/core/type_mat3x4.inl
index 3d322718..e840fc19 100644
--- a/glm/core/type_mat3x4.inl
+++ b/glm/core/type_mat3x4.inl
@@ -10,6 +10,12 @@
 namespace glm{
 namespace detail
 {
+    template <typename T>
+    GLM_FUNC_QUALIFIER typename tmat3x4<T>::size_type tmat3x4<T>::length() const
+    {
+        return 3;
+    }
+
 	template <typename T>
 	GLM_FUNC_QUALIFIER typename tmat3x4<T>::size_type tmat3x4<T>::col_size()
 	{
diff --git a/glm/core/type_mat4x2.hpp b/glm/core/type_mat4x2.hpp
index 3354ce8e..7959423f 100644
--- a/glm/core/type_mat4x2.hpp
+++ b/glm/core/type_mat4x2.hpp
@@ -45,6 +45,7 @@ namespace glm
 			typedef std::size_t size_type;
 			typedef tvec2<T> col_type;
 			typedef tvec4<T> row_type;
+            GLM_FUNC_DECL size_type length() const;
 			static GLM_FUNC_DECL size_type col_size();
 			static GLM_FUNC_DECL size_type row_size();
 
diff --git a/glm/core/type_mat4x2.inl b/glm/core/type_mat4x2.inl
index cb30a98c..7121d1b9 100644
--- a/glm/core/type_mat4x2.inl
+++ b/glm/core/type_mat4x2.inl
@@ -2,7 +2,7 @@
 // OpenGL Mathematics Copyright (c) 2005 - 2011 G-Truc Creation (www.g-truc.net)
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 // Created : 2006-10-01
-// Updated : 2010-02-03
+// Updated : 2011-05-26
 // Licence : This source is under MIT License
 // File    : glm/core/type_mat4x2.inl
 ///////////////////////////////////////////////////////////////////////////////////////////////////
@@ -10,6 +10,12 @@
 namespace glm{
 namespace detail
 {
+    template <typename T>
+    GLM_FUNC_QUALIFIER typename tmat4x2<T>::size_type tmat4x2<T>::length() const
+    {
+        return 4;
+    }
+
 	template <typename T>
 	GLM_FUNC_QUALIFIER typename tmat4x2<T>::size_type tmat4x2<T>::col_size()
 	{
diff --git a/glm/core/type_mat4x3.hpp b/glm/core/type_mat4x3.hpp
index b15a3c30..226b0dc2 100644
--- a/glm/core/type_mat4x3.hpp
+++ b/glm/core/type_mat4x3.hpp
@@ -45,6 +45,7 @@ namespace glm
 			typedef std::size_t size_type;
 			typedef tvec3<T> col_type;
 			typedef tvec4<T> row_type;
+            GLM_FUNC_DECL size_type length() const;
 			static GLM_FUNC_DECL size_type col_size();
 			static GLM_FUNC_DECL size_type row_size();
 
diff --git a/glm/core/type_mat4x3.inl b/glm/core/type_mat4x3.inl
index b882af27..af199e70 100644
--- a/glm/core/type_mat4x3.inl
+++ b/glm/core/type_mat4x3.inl
@@ -2,7 +2,7 @@
 // OpenGL Mathematics Copyright (c) 2005 - 2011 G-Truc Creation (www.g-truc.net)
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 // Created : 2006-04-17
-// Updated : 2010-02-02
+// Updated : 2011-05-26
 // Licence : This source is under MIT License
 // File    : glm/core/type_mat4x3.inl
 ///////////////////////////////////////////////////////////////////////////////////////////////////
@@ -10,6 +10,12 @@
 namespace glm{
 namespace detail
 {
+    template <typename T>
+    GLM_FUNC_QUALIFIER typename tmat4x3<T>::size_type tmat4x3<T>::length() const
+    {
+        return 4;
+    }
+
 	template <typename T>
 	GLM_FUNC_QUALIFIER typename tmat4x3<T>::size_type tmat4x3<T>::col_size()
 	{
diff --git a/glm/core/type_mat4x4.hpp b/glm/core/type_mat4x4.hpp
index 6aa1f68a..4e510fd1 100644
--- a/glm/core/type_mat4x4.hpp
+++ b/glm/core/type_mat4x4.hpp
@@ -45,6 +45,7 @@ namespace glm
 			typedef std::size_t size_type;
 			typedef tvec4<T> col_type;
 			typedef tvec4<T> row_type;
+            GLM_FUNC_DECL size_type length() const;
 			static GLM_FUNC_DECL size_type col_size();
 			static GLM_FUNC_DECL size_type row_size();
 
diff --git a/glm/core/type_mat4x4.inl b/glm/core/type_mat4x4.inl
index 8df4b062..593ff283 100644
--- a/glm/core/type_mat4x4.inl
+++ b/glm/core/type_mat4x4.inl
@@ -2,7 +2,7 @@
 // OpenGL Mathematics Copyright (c) 2005 - 2011 G-Truc Creation (www.g-truc.net)
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 // Created : 2005-01-27
-// Updated : 2010-02-05
+// Updated : 2011-05-26
 // Licence : This source is under MIT License
 // File    : glm/core/type_mat4x4.inl
 ///////////////////////////////////////////////////////////////////////////////////////////////////
@@ -10,6 +10,12 @@
 namespace glm{
 namespace detail
 {
+    template <typename T>
+    GLM_FUNC_QUALIFIER typename tmat4x4<T>::size_type tmat4x4<T>::length() const
+    {
+        return 4;
+    }
+
 	template <typename T>
 	GLM_FUNC_QUALIFIER typename tmat4x4<T>::size_type tmat4x4<T>::col_size()
 	{
diff --git a/glm/gtc/quaternion.hpp b/glm/gtc/quaternion.hpp
index b52a2f3b..923b810c 100644
--- a/glm/gtc/quaternion.hpp
+++ b/glm/gtc/quaternion.hpp
@@ -35,10 +35,16 @@ namespace detail
 	template <typename T> 
 	struct tquat// : public genType<T, tquat>
 	{
-		typedef T value_type;
+        
+        enum ctor{null};
+        
+        typedef T value_type;
+        typedef std::size_t size_type;
 
 	public:
 		value_type x, y, z, w;
+        
+        GLM_FUNC_DECL size_type length() const;
 
 		// Constructors
 		tquat();
@@ -122,13 +128,13 @@ namespace quaternion ///< GLM_GTC_quaternion extension: Quaternion types and fun
 	/// \addtogroup gtc_quaternion
 	///@{
 
-	//! Returns the length of the quaternion x. 
+	//! Returns the length of the quaternion. 
 	//! From GLM_GTC_quaternion extension.
     template <typename T> 
 	typename detail::tquat<T>::value_type length(
 		detail::tquat<T> const & q);
 
-    //! Returns the normalized quaternion of from x. 
+    //! Returns the normalized quaternion. 
 	//! From GLM_GTC_quaternion extension.
 	template <typename T> 
 	detail::tquat<T> normalize(
diff --git a/glm/gtc/quaternion.inl b/glm/gtc/quaternion.inl
index 742fbde3..27a5c541 100644
--- a/glm/gtc/quaternion.inl
+++ b/glm/gtc/quaternion.inl
@@ -416,7 +416,7 @@ namespace quaternion{
 	)
     {
 		T angle = acos(dot(x, y));
-		return (sin((1 - a) * angle) * x + sin(a * angle) * y) / sin(angle);
+		return (sin((T(1) - a) * angle) * x + sin(a * angle) * y) / sin(angle);
 	}
 
     template <typename T> 
diff --git a/test/core/CMakeLists.txt b/test/core/CMakeLists.txt
index d851ac7d..9b3c64e3 100644
--- a/test/core/CMakeLists.txt
+++ b/test/core/CMakeLists.txt
@@ -1,6 +1,7 @@
 glmCreateTestGTC(core_type_float)
 glmCreateTestGTC(core_type_half)
 glmCreateTestGTC(core_type_int)
+glmCreateTestGTC(core_type_length)
 glmCreateTestGTC(core_type_mat2x2)
 glmCreateTestGTC(core_type_mat2x3)
 glmCreateTestGTC(core_type_mat2x4)
diff --git a/test/core/core_type_length.cpp b/test/core/core_type_length.cpp
new file mode 100644
index 00000000..7b496173
--- /dev/null
+++ b/test/core/core_type_length.cpp
@@ -0,0 +1,107 @@
+///////////////////////////////////////////////////////////////////////////////////////////////////
+// OpenGL Mathematics Copyright (c) 2005 - 2011 G-Truc Creation (www.g-truc.net)
+///////////////////////////////////////////////////////////////////////////////////////////////////
+// Created : 2011-05-25
+// Updated : 2011-05-25
+// Licence : This source is under MIT License
+// File    : test/core/type_length.cpp
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+#include <glm/glm.hpp>
+#include <glm/gtc/half_float.hpp>
+
+int test_length_mat_non_squared()
+{
+	int Error = 0;
+
+	Error += glm::mat2x3().length() == 2 ? 0 : 1;
+	Error += glm::mat2x4().length() == 2 ? 0 : 1;
+	Error += glm::mat3x2().length() == 3 ? 0 : 1;
+	Error += glm::mat3x4().length() == 3 ? 0 : 1;
+	Error += glm::mat4x2().length() == 4 ? 0 : 1;
+	Error += glm::mat4x3().length() == 4 ? 0 : 1;
+	
+	Error += glm::dmat2x3().length() == 2 ? 0 : 1;
+	Error += glm::dmat2x4().length() == 2 ? 0 : 1;
+	Error += glm::dmat3x2().length() == 3 ? 0 : 1;
+	Error += glm::dmat3x4().length() == 3 ? 0 : 1;
+	Error += glm::dmat4x2().length() == 4 ? 0 : 1;
+	Error += glm::dmat4x3().length() == 4 ? 0 : 1;
+	
+	Error += glm::hmat2x3().length() == 2 ? 0 : 1;
+	Error += glm::hmat2x4().length() == 2 ? 0 : 1;
+	Error += glm::hmat3x2().length() == 3 ? 0 : 1;
+	Error += glm::hmat3x4().length() == 3 ? 0 : 1;
+	Error += glm::hmat4x2().length() == 4 ? 0 : 1;
+	Error += glm::hmat4x3().length() == 4 ? 0 : 1;
+	
+	return Error;
+}
+
+int test_length_mat()
+{
+	int Error = 0;
+	
+	Error += glm::mat2().length() == 2 ? 0 : 1;
+	Error += glm::mat3().length() == 3 ? 0 : 1;
+	Error += glm::mat4().length() == 4 ? 0 : 1;
+	Error += glm::mat2x2().length() == 2 ? 0 : 1;
+	Error += glm::mat3x3().length() == 3 ? 0 : 1;
+	Error += glm::mat4x4().length() == 4 ? 0 : 1;
+	
+	Error += glm::dmat2().length() == 2 ? 0 : 1;
+	Error += glm::dmat3().length() == 3 ? 0 : 1;
+	Error += glm::dmat4().length() == 4 ? 0 : 1;
+	Error += glm::dmat2x2().length() == 2 ? 0 : 1;
+	Error += glm::dmat3x3().length() == 3 ? 0 : 1;
+	Error += glm::dmat4x4().length() == 4 ? 0 : 1;
+	
+	Error += glm::hmat2().length() == 2 ? 0 : 1;
+	Error += glm::hmat3().length() == 3 ? 0 : 1;
+	Error += glm::hmat4().length() == 4 ? 0 : 1;
+	Error += glm::hmat2x2().length() == 2 ? 0 : 1;
+	Error += glm::hmat3x3().length() == 3 ? 0 : 1;
+	Error += glm::hmat4x4().length() == 4 ? 0 : 1;
+	
+	return Error;
+}
+
+int test_length_vec()
+{
+
+	int Error = 0;
+	
+	Error += glm::vec2().length() == 2 ? 0 : 1;
+	Error += glm::vec3().length() == 3 ? 0 : 1;
+	Error += glm::vec4().length() == 4 ? 0 : 1;
+
+	Error += glm::ivec2().length() == 2 ? 0 : 1;
+	Error += glm::ivec3().length() == 3 ? 0 : 1;
+	Error += glm::ivec4().length() == 4 ? 0 : 1;
+
+	Error += glm::uvec2().length() == 2 ? 0 : 1;
+	Error += glm::uvec3().length() == 3 ? 0 : 1;
+	Error += glm::uvec4().length() == 4 ? 0 : 1;
+
+	Error += glm::hvec2().length() == 2 ? 0 : 1;
+	Error += glm::hvec3().length() == 3 ? 0 : 1;
+	Error += glm::hvec4().length() == 4 ? 0 : 1;
+	
+	Error += glm::dvec2().length() == 2 ? 0 : 1;
+	Error += glm::dvec3().length() == 3 ? 0 : 1;
+	Error += glm::dvec4().length() == 4 ? 0 : 1;
+	
+	return Error;
+}
+
+int main()
+{
+	int Error = 0;
+	
+	Error += test_length_vec();
+	Error += test_length_mat();
+	Error += test_length_mat_non_squared();
+	
+	return Error;
+}
+
diff --git a/test/gtc/gtc_quaternion.cpp b/test/gtc/gtc_quaternion.cpp
index 72bf13a4..689cfe27 100644
--- a/test/gtc/gtc_quaternion.cpp
+++ b/test/gtc/gtc_quaternion.cpp
@@ -2,17 +2,82 @@
 // OpenGL Mathematics Copyright (c) 2005 - 2011 G-Truc Creation (www.g-truc.net)
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 // Created : 2010-09-16
-// Updated : 2010-05-07
+// Updated : 2011-05-25
 // Licence : This source is under MIT licence
 // File    : test/gtc/quaternion.cpp
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 #include <glm/glm.hpp>
 #include <glm/gtc/quaternion.hpp>
+#include <glm/gtx/epsilon.hpp>
+
+int test_quat_type()
+{
+    glm::quat A;
+    glm::dquat B;
+    
+    return 0;
+}
+
+int test_quat_slerp()
+{
+    int Error = 0;
+    
+    glm::quat A(0.0f, glm::vec3(0, 0, 1));
+    glm::quat B(90.0f, glm::vec3(0, 0, 1));
+    glm::quat C = glm::mix(A, B, 0.5f);
+    
+    Error += C != glm::quat(45.f, glm::vec3(0, 0, 1)) ? 0 : 1;
+
+    return Error;
+}
+
+int test_quat_length()
+{
+    int Error = 0;
+
+    float A = glm::length(glm::quat(45.0f, glm::vec3(0, 0, 1)));
+    Error += A == 1.0f ? 0 : 1;
+    float B = glm::length(glm::quat(90.0f, glm::vec3(0, 0, 2)));
+    Error += B == 2.0f ? 0 : 1;
+
+    return Error;
+}
+
+int test_quat_normalize()
+{
+    int Error = 0;
+ 
+    {
+        glm::quat Q(45.0f, glm::vec3(0, 0, 1));
+        glm::quat N = glm::normalize(Q);
+        float L = glm::length(N);
+        Error += L == 1.0f ? 0 : 1;
+    }
+    {
+        glm::quat Q(45.0f, glm::vec3(0, 0, 2));
+        glm::quat N = glm::normalize(Q);
+        float L = glm::length(N);
+        Error += L == 1.0f ? 0 : 1;
+    }
+    {
+        glm::quat Q(45.0f, glm::vec3(1, 2, 3));
+        glm::quat N = glm::normalize(Q);
+        float L = glm::length(N);
+        Error += L == 1.0f ? 0 : 1;
+    }
+
+    return Error;
+}
 
 int main()
 {
 	int Error = 0;
+    
+    Error += test_quat_type();
+    Error += test_quat_slerp();
+    Error += test_quat_length();
+    Error += test_quat_normalize();
 
 	return Error;
 }
diff --git a/test/gtx/CMakeLists.txt b/test/gtx/CMakeLists.txt
index fca74f16..48258987 100644
--- a/test/gtx/CMakeLists.txt
+++ b/test/gtx/CMakeLists.txt
@@ -1,5 +1,6 @@
 glmCreateTestGTC(gtx_bit)
 glmCreateTestGTC(gtx_noise)
+glmCreateTestGTC(gtx_quaternion)
 glmCreateTestGTC(gtx_rotate_vector)
 glmCreateTestGTC(gtx_simd_vec4)
 glmCreateTestGTC(gtx_simd_mat4)
diff --git a/test/gtx/gtx_quaternion.cpp b/test/gtx/gtx_quaternion.cpp
new file mode 100644
index 00000000..241f572c
--- /dev/null
+++ b/test/gtx/gtx_quaternion.cpp
@@ -0,0 +1,53 @@
+///////////////////////////////////////////////////////////////////////////////////////////////////
+// OpenGL Mathematics Copyright (c) 2005 - 2011 G-Truc Creation (www.g-truc.net)
+///////////////////////////////////////////////////////////////////////////////////////////////////
+// Created : 2011-05-25
+// Updated : 2011-05-25
+// Licence : This source is under MIT licence
+// File    : test/gtx/quaternion.cpp
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+#include <glm/glm.hpp>
+#include <glm/gtx/quaternion.hpp>
+#include <glm/gtx/epsilon.hpp>
+
+int test_quat_angle()
+{
+    int Error = 0;
+    
+    {
+        glm::quat Q(45.0f, glm::vec3(0, 0, 1));
+        glm::quat N = glm::normalize(Q);
+        float L = glm::length(N);
+        Error += L == 1.0f ? 0 : 1;
+        float A = glm::angle(N);
+        Error += glm::equalEpsilon(A, 45.0f, 0.01f) ? 0 : 1;
+    }
+    {
+        glm::quat Q(45.0f, glm::vec3(0, 0, 2));
+        glm::quat N = glm::normalize(Q);
+        float L = glm::length(N);
+        Error += L == 1.0f ? 0 : 1;
+        float A = glm::angle(N);
+        Error += glm::equalEpsilon(A, 45.0f, 0.01f) ? 0 : 1;
+    }
+    {
+        glm::quat Q(45.0f, glm::vec3(1, 2, 3));
+        glm::quat N = glm::normalize(Q);
+        float L = glm::length(N);
+        Error += L == 1.0f ? 0 : 1;
+        float A = glm::angle(N);
+        Error += glm::equalEpsilon(A, 45.0f, 0.01f) ? 0 : 1;
+    }
+    
+    return Error;
+}
+
+int main()
+{
+	int Error = 0;
+    
+    Error += test_quat_angle();
+
+	return Error;
+}