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/texture.hpp

@@ -0,0 +1,46 @@
+/// @ref gtx_texture
+/// @file glm/gtx/texture.hpp
+///
+/// @see core (dependence)
+///
+/// @defgroup gtx_texture GLM_GTX_texture
+/// @ingroup gtx
+///
+/// Include <glm/gtx/texture.hpp> to use the features of this extension.
+///
+/// Wrapping mode of texture coordinates.
+
+#pragma once
+
+// Dependency:
+#include "../glm.hpp"
+#include "../gtc/integer.hpp"
+#include "../gtx/component_wise.hpp"
+
+#ifndef GLM_ENABLE_EXPERIMENTAL
+#	error "GLM: GLM_GTX_texture is an experimental extension and may change in the future. Use #define GLM_ENABLE_EXPERIMENTAL before including it, if you really want to use it."
+#endif
+
+#if GLM_MESSAGES == GLM_ENABLE && !defined(GLM_EXT_INCLUDED)
+#	pragma message("GLM: GLM_GTX_texture extension included")
+#endif
+
+namespace glm
+{
+	/// @addtogroup gtx_texture
+	/// @{
+
+	/// Compute the number of mipmaps levels necessary to create a mipmap complete texture
+	///
+	/// @param Extent Extent of the texture base level mipmap
+	/// @tparam L Integer between 1 and 4 included that qualify the dimension of the vector
+	/// @tparam T Floating-point or signed integer scalar types
+	/// @tparam Q Value from qualifier enum
+	template <length_t L, typename T, qualifier Q>
+	T levels(vec<L, T, Q> const& Extent);
+
+	/// @}
+}// namespace glm
+
+#include "texture.inl"
+