Add ktx

ktx/other_include/glm/gtx/perpendicular.inl

@@ -0,0 +1,15 @@
+/// @ref gtx_perpendicular
+/// @file glm/gtx/perpendicular.inl
+
+namespace glm
+{
+	template<typename vecType> 
+	GLM_FUNC_QUALIFIER vecType perp
+	(
+		vecType const & x, 
+		vecType const & Normal
+	)
+	{
+		return x - proj(x, Normal);
+	}
+}//namespace glm