tests: Check glm into source control to make Windows build simpler
diff --git a/libs/glm/gtx/matrix_interpolation.hpp b/libs/glm/gtx/matrix_interpolation.hpp
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+///////////////////////////////////////////////////////////////////////////////////
+/// OpenGL Mathematics (glm.g-truc.net)
+///
+/// Copyright (c) 2005 - 2014 G-Truc Creation (www.g-truc.net)
+/// Permission is hereby granted, free of charge, to any person obtaining a copy
+/// of this software and associated documentation files (the "Software"), to deal
+/// in the Software without restriction, including without limitation the rights
+/// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+/// copies of the Software, and to permit persons to whom the Software is
+/// furnished to do so, subject to the following conditions:
+/// 
+/// The above copyright notice and this permission notice shall be included in
+/// all copies or substantial portions of the Software.
+/// 
+/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+/// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+/// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+/// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+/// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+/// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+/// THE SOFTWARE.
+///
+/// @ref gtx_matrix_interpolation
+/// @file glm/gtx/matrix_interpolation.hpp
+/// @date 2011-03-05 / 2011-06-07
+/// @author Ghenadii Ursachi (the.asteroth@gmail.com)
+///
+/// @see core (dependence)
+///
+/// @defgroup gtx_matrix_interpolation GLM_GTX_matrix_interpolation
+/// @ingroup gtx
+/// 
+/// @brief Allows to directly interpolate two exiciting matrices.
+/// 
+/// <glm/gtx/matrix_interpolation.hpp> need to be included to use these functionalities.
+///////////////////////////////////////////////////////////////////////////////////
+
+#ifndef GLM_GTX_matrix_interpolation
+#define GLM_GTX_matrix_interpolation
+
+// Dependency:
+#include "../glm.hpp"
+
+#if(defined(GLM_MESSAGES) && !defined(GLM_EXT_INCLUDED))
+#	pragma message("GLM: GLM_GTX_matrix_interpolation extension included")
+#endif
+
+namespace glm
+{
+	/// @addtogroup gtx_matrix_interpolation
+	/// @{
+
+	/// Get the axis and angle of the rotation from a matrix.
+	/// From GLM_GTX_matrix_interpolation extension.
+	template <typename T, precision P>
+	GLM_FUNC_DECL void axisAngle(
+		detail::tmat4x4<T, P> const & mat,
+		detail::tvec3<T, P> & axis,
+		T & angle);
+
+	/// Build a matrix from axis and angle.
+	/// From GLM_GTX_matrix_interpolation extension.
+	template <typename T, precision P>
+	GLM_FUNC_DECL detail::tmat4x4<T, P> axisAngleMatrix(
+		detail::tvec3<T, P> const & axis,
+		T const angle);
+
+	/// Extracts the rotation part of a matrix.
+	/// From GLM_GTX_matrix_interpolation extension.
+	template <typename T, precision P>
+	GLM_FUNC_DECL detail::tmat4x4<T, P> extractMatrixRotation(
+		detail::tmat4x4<T, P> const & mat);
+
+	/// Build a interpolation of 4 * 4 matrixes.
+	/// From GLM_GTX_matrix_interpolation extension.
+	/// Warning! works only with rotation and/or translation matrixes, scale will generate unexpected results.
+	template <typename T, precision P>
+	GLM_FUNC_DECL detail::tmat4x4<T, P> interpolate(
+		detail::tmat4x4<T, P> const & m1,
+		detail::tmat4x4<T, P> const & m2,
+		T const delta);
+
+	/// @}
+}//namespace glm
+
+#include "matrix_interpolation.inl"
+
+#endif//GLM_GTX_matrix_interpolation