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+/// @ref gtx_matrix_decompose
+/// @file glm/gtx/matrix_decompose.inl
+
+namespace glm{
+namespace detail
+{
+	/// Make a linear combination of two vectors and return the result.
+	// result = (a * ascl) + (b * bscl)
+	template <typename T, precision P>
+	GLM_FUNC_QUALIFIER tvec3<T, P> combine(
+		tvec3<T, P> const & a, 
+		tvec3<T, P> const & b,
+		T ascl, T bscl)
+	{
+		return (a * ascl) + (b * bscl);
+	}
+
+	template <typename T, precision P>
+	GLM_FUNC_QUALIFIER tvec3<T, P> scale(tvec3<T, P> const& v, T desiredLength)
+	{
+		return v * desiredLength / length(v);
+	}
+}//namespace detail
+
+	// Matrix decompose
+	// http://www.opensource.apple.com/source/WebCore/WebCore-514/platform/graphics/transforms/TransformationMatrix.cpp
+	// Decomposes the mode matrix to translations,rotation scale components
+
+	template <typename T, precision P>
+	GLM_FUNC_QUALIFIER bool decompose(tmat4x4<T, P> const & ModelMatrix, tvec3<T, P> & Scale, tquat<T, P> & Orientation, tvec3<T, P> & Translation, tvec3<T, P> & Skew, tvec4<T, P> & Perspective)
+	{
+		tmat4x4<T, P> LocalMatrix(ModelMatrix);
+
+		// Normalize the matrix.
+		if(LocalMatrix[3][3] == static_cast<T>(0))
+			return false;
+
+		for(length_t i = 0; i < 4; ++i)
+		for(length_t j = 0; j < 4; ++j)
+			LocalMatrix[i][j] /= LocalMatrix[3][3];
+
+		// perspectiveMatrix is used to solve for perspective, but it also provides
+		// an easy way to test for singularity of the upper 3x3 component.
+		tmat4x4<T, P> PerspectiveMatrix(LocalMatrix);
+
+		for(length_t i = 0; i < 3; i++)
+			PerspectiveMatrix[i][3] = static_cast<T>(0);
+		PerspectiveMatrix[3][3] = static_cast<T>(1);
+
+		/// TODO: Fixme!
+		if(determinant(PerspectiveMatrix) == static_cast<T>(0))
+			return false;
+
+		// First, isolate perspective.  This is the messiest.
+		if(LocalMatrix[0][3] != static_cast<T>(0) || LocalMatrix[1][3] != static_cast<T>(0) || LocalMatrix[2][3] != static_cast<T>(0))
+		{
+			// rightHandSide is the right hand side of the equation.
+			tvec4<T, P> RightHandSide;
+			RightHandSide[0] = LocalMatrix[0][3];
+			RightHandSide[1] = LocalMatrix[1][3];
+			RightHandSide[2] = LocalMatrix[2][3];
+			RightHandSide[3] = LocalMatrix[3][3];
+
+			// Solve the equation by inverting PerspectiveMatrix and multiplying
+			// rightHandSide by the inverse.  (This is the easiest way, not
+			// necessarily the best.)
+			tmat4x4<T, P> InversePerspectiveMatrix = glm::inverse(PerspectiveMatrix);//   inverse(PerspectiveMatrix, inversePerspectiveMatrix);
+			tmat4x4<T, P> TransposedInversePerspectiveMatrix = glm::transpose(InversePerspectiveMatrix);//   transposeMatrix4(inversePerspectiveMatrix, transposedInversePerspectiveMatrix);
+
+			Perspective = TransposedInversePerspectiveMatrix * RightHandSide;
+			//  v4MulPointByMatrix(rightHandSide, transposedInversePerspectiveMatrix, perspectivePoint);
+
+			// Clear the perspective partition
+			LocalMatrix[0][3] = LocalMatrix[1][3] = LocalMatrix[2][3] = static_cast<T>(0);
+			LocalMatrix[3][3] = static_cast<T>(1);
+		}
+		else
+		{
+			// No perspective.
+			Perspective = tvec4<T, P>(0, 0, 0, 1);
+		}
+
+		// Next take care of translation (easy).
+		Translation = tvec3<T, P>(LocalMatrix[3]);
+		LocalMatrix[3] = tvec4<T, P>(0, 0, 0, LocalMatrix[3].w);
+
+		tvec3<T, P> Row[3], Pdum3;
+
+		// Now get scale and shear.
+		for(length_t i = 0; i < 3; ++i)
+			for(int j = 0; j < 3; ++j)
+				Row[i][j] = LocalMatrix[i][j];
+
+		// Compute X scale factor and normalize first row.
+		Scale.x = length(Row[0]);// v3Length(Row[0]);
+
+		Row[0] = detail::scale(Row[0], static_cast<T>(1));
+
+		// Compute XY shear factor and make 2nd row orthogonal to 1st.
+		Skew.z = dot(Row[0], Row[1]);
+		Row[1] = detail::combine(Row[1], Row[0], static_cast<T>(1), -Skew.z);
+
+		// Now, compute Y scale and normalize 2nd row.
+		Scale.y = length(Row[1]);
+		Row[1] = detail::scale(Row[1], static_cast<T>(1));
+		Skew.z /= Scale.y;
+
+		// Compute XZ and YZ shears, orthogonalize 3rd row.
+		Skew.y = glm::dot(Row[0], Row[2]);
+		Row[2] = detail::combine(Row[2], Row[0], static_cast<T>(1), -Skew.y);
+		Skew.x = glm::dot(Row[1], Row[2]);
+		Row[2] = detail::combine(Row[2], Row[1], static_cast<T>(1), -Skew.x);
+
+		// Next, get Z scale and normalize 3rd row.
+		Scale.z = length(Row[2]);
+		Row[2] = detail::scale(Row[2], static_cast<T>(1));
+		Skew.y /= Scale.z;
+		Skew.x /= Scale.z;
+
+		// At this point, the matrix (in rows[]) is orthonormal.
+		// Check for a coordinate system flip.  If the determinant
+		// is -1, then negate the matrix and the scaling factors.
+		Pdum3 = cross(Row[1], Row[2]); // v3Cross(row[1], row[2], Pdum3);
+		if(dot(Row[0], Pdum3) < 0)
+		{
+			for(length_t i = 0; i < 3; i++)
+			{
+				Scale[i] *= static_cast<T>(-1);
+				Row[i] *= static_cast<T>(-1);
+			}
+		}
+
+		// Now, get the rotations out, as described in the gem.
+
+		// FIXME - Add the ability to return either quaternions (which are
+		// easier to recompose with) or Euler angles (rx, ry, rz), which
+		// are easier for authors to deal with. The latter will only be useful
+		// when we fix https://bugs.webkit.org/show_bug.cgi?id=23799, so I
+		// will leave the Euler angle code here for now.
+
+		// ret.rotateY = asin(-Row[0][2]);
+		// if (cos(ret.rotateY) != 0) {
+		//     ret.rotateX = atan2(Row[1][2], Row[2][2]);
+		//     ret.rotateZ = atan2(Row[0][1], Row[0][0]);
+		// } else {
+		//     ret.rotateX = atan2(-Row[2][0], Row[1][1]);
+		//     ret.rotateZ = 0;
+		// }
+
+		T s, t, x, y, z, w;
+
+		t = Row[0][0] + Row[1][1] + Row[2][2] + static_cast<T>(1);
+
+		if(t > static_cast<T>(1e-4))
+		{
+			s = static_cast<T>(0.5) / sqrt(t);
+			w = static_cast<T>(0.25) / s;
+			x = (Row[2][1] - Row[1][2]) * s;
+			y = (Row[0][2] - Row[2][0]) * s;
+			z = (Row[1][0] - Row[0][1]) * s;
+		}
+		else if(Row[0][0] > Row[1][1] && Row[0][0] > Row[2][2])
+		{ 
+			s = sqrt (static_cast<T>(1) + Row[0][0] - Row[1][1] - Row[2][2]) * static_cast<T>(2); // S=4*qx 
+			x = static_cast<T>(0.25) * s;
+			y = (Row[0][1] + Row[1][0]) / s; 
+			z = (Row[0][2] + Row[2][0]) / s; 
+			w = (Row[2][1] - Row[1][2]) / s;
+		}
+		else if(Row[1][1] > Row[2][2])
+		{ 
+			s = sqrt (static_cast<T>(1) + Row[1][1] - Row[0][0] - Row[2][2]) * static_cast<T>(2); // S=4*qy
+			x = (Row[0][1] + Row[1][0]) / s; 
+			y = static_cast<T>(0.25) * s;
+			z = (Row[1][2] + Row[2][1]) / s; 
+			w = (Row[0][2] - Row[2][0]) / s;
+		}
+		else
+		{ 
+			s = sqrt(static_cast<T>(1) + Row[2][2] - Row[0][0] - Row[1][1]) * static_cast<T>(2); // S=4*qz
+			x = (Row[0][2] + Row[2][0]) / s;
+			y = (Row[1][2] + Row[2][1]) / s; 
+			z = static_cast<T>(0.25) * s;
+			w = (Row[1][0] - Row[0][1]) / s;
+		}
+
+		Orientation.x = x;
+		Orientation.y = y;
+		Orientation.z = z;
+		Orientation.w = w;
+
+		return true;
+	}
+}//namespace glm