Fixed epsilon for half types

glm/gtc/constants.inl

@@ -34,6 +34,12 @@ namespace glm
 		return std::numeric_limits<T>::epsilon();
 	}
 
+	template <>
+	GLM_FUNC_QUALIFIER GLM_CONSTEXPR half epsilon()
+	{
+		return half(1.19209290e-007);
+	}
+
 	template <typename T>
 	GLM_FUNC_QUALIFIER GLM_CONSTEXPR T zero()
 	{