Update GLM to latest version (0.9.9.3). This includes GLM's change of matrices no longer default initializing to the identity matrix. This commit thus also includes the update of all of LearnOpenGL's code to reflect this: all matrices are now constructor-initialized to the identity matrix where relevant.

includes/glm/gtx/functions.hpp

@@ -0,0 +1,52 @@
+/// @ref gtx_functions
+/// @file glm/gtx/functions.hpp
+///
+/// @see core (dependence)
+/// @see gtc_quaternion (dependence)
+///
+/// @defgroup gtx_functions GLM_GTX_functions
+/// @ingroup gtx
+///
+/// Include <glm/gtx/functions.hpp> to use the features of this extension.
+///
+/// List of useful common functions.
+
+#pragma once
+
+// Dependencies
+#include "../detail/setup.hpp"
+#include "../detail/qualifier.hpp"
+#include "../detail/type_vec2.hpp"
+
+#if GLM_MESSAGES == GLM_ENABLE && !defined(GLM_EXT_INCLUDED)
+#	pragma message("GLM: GLM_GTX_functions extension included")
+#endif
+
+namespace glm
+{
+	/// @addtogroup gtx_functions
+	/// @{
+
+	/// 1D gauss function
+	///
+	/// @see gtc_epsilon
+	template<typename T>
+	GLM_FUNC_DECL T gauss(
+		T x,
+		T ExpectedValue,
+		T StandardDeviation);
+
+	/// 2D gauss function
+	///
+	/// @see gtc_epsilon
+	template<typename T, qualifier Q>
+	GLM_FUNC_DECL T gauss(
+		vec<2, T, Q> const& Coord,
+		vec<2, T, Q> const& ExpectedValue,
+		vec<2, T, Q> const& StandardDeviation);
+
+	/// @}
+}//namespace glm
+
+#include "functions.inl"
+