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/quaternion_relational.hpp

@@ -0,0 +1,62 @@
+/// @ref ext_quaternion_relational
+/// @file glm/ext/quaternion_relational.hpp
+///
+/// @defgroup ext_quaternion_relational GLM_EXT_quaternion_relational
+/// @ingroup ext
+///
+/// Exposes comparison functions for quaternion types that take a user defined epsilon values.
+///
+/// Include <glm/ext/quaternion_relational.hpp> to use the features of this extension.
+///
+/// @see core_vector_relational
+/// @see ext_vector_relational
+/// @see ext_matrix_relational
+/// @see ext_quaternion_float
+/// @see ext_quaternion_double
+
+#pragma once
+
+// Dependency:
+#include "../vector_relational.hpp"
+
+#if GLM_MESSAGES == GLM_ENABLE && !defined(GLM_EXT_INCLUDED)
+#	pragma message("GLM: GLM_EXT_quaternion_relational extension included")
+#endif
+
+namespace glm
+{
+	/// @addtogroup ext_quaternion_relational
+	/// @{
+
+	/// Returns the component-wise comparison of result x == y.
+	///
+	/// @tparam T Floating-point scalar types
+	/// @tparam Q Value from qualifier enum
+	template<typename T, qualifier Q>
+	GLM_FUNC_DECL vec<4, bool, Q> equal(qua<T, Q> const& x, qua<T, Q> const& y);
+
+	/// Returns the component-wise comparison of |x - y| < epsilon.
+	///
+	/// @tparam T Floating-point scalar types
+	/// @tparam Q Value from qualifier enum
+	template<typename T, qualifier Q>
+	GLM_FUNC_DECL vec<4, bool, Q> equal(qua<T, Q> const& x, qua<T, Q> const& y, T epsilon);
+
+	/// Returns the component-wise comparison of result x != y.
+	///
+	/// @tparam T Floating-point scalar types
+	/// @tparam Q Value from qualifier enum
+	template<typename T, qualifier Q>
+	GLM_FUNC_DECL vec<4, bool, Q> notEqual(qua<T, Q> const& x, qua<T, Q> const& y);
+
+	/// Returns the component-wise comparison of |x - y| >= epsilon.
+	///
+	/// @tparam T Floating-point scalar types
+	/// @tparam Q Value from qualifier enum
+	template<typename T, qualifier Q>
+	GLM_FUNC_DECL vec<4, bool, Q> notEqual(qua<T, Q> const& x, qua<T, Q> const& y, T epsilon);
+
+	/// @}
+} //namespace glm
+
+#include "quaternion_relational.inl"