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/ext/vector_double1.hpp

@@ -0,0 +1,31 @@
+/// @ref ext_vector_double1
+/// @file glm/ext/vector_double1.hpp
+///
+/// @defgroup ext_vector_double1 GLM_EXT_vector_double1
+/// @ingroup ext
+///
+/// Exposes double-precision floating point vector type with one component.
+///
+/// Include <glm/ext/vector_double1.hpp> to use the features of this extension.
+///
+/// @see ext_vector_double1_precision extension.
+/// @see ext_vector_float1 extension.
+
+#pragma once
+
+#include "../detail/type_vec1.hpp"
+
+#if GLM_MESSAGES == GLM_ENABLE && !defined(GLM_EXT_INCLUDED)
+#	pragma message("GLM: GLM_EXT_vector_dvec1 extension included")
+#endif
+
+namespace glm
+{
+	/// @addtogroup ext_vector_double1
+	/// @{
+
+	/// 1 components vector of double-precision floating-point numbers.
+	typedef vec<1, double, defaultp>		dvec1;
+
+	/// @}
+}//namespace glm