[Feat] (...): Add GLES Backend.

include/glm/gtx/normal.inl

@@ -0,0 +1,15 @@
+/// @ref gtx_normal
+
+namespace glm
+{
+	template<typename T, qualifier Q>
+	GLM_FUNC_QUALIFIER vec<3, T, Q> triangleNormal
+	(
+		vec<3, T, Q> const& p1,
+		vec<3, T, Q> const& p2,
+		vec<3, T, Q> const& p3
+	)
+	{
+		return normalize(cross(p1 - p2, p1 - p3));
+	}
+}//namespace glm