A method of determining an orientation of a respective object having an interface surface with coded data. The coded data includes a plurality of coded data portions provided at respective positions on the interface surface. Each coded data portion is indicative of an identity of the object. The method includes, in a sensing device, sensing at least one coded data portion, generating, using the sensed coded data portion, indicating data indicative of the object identity. The method also includes generating indicating data indicative of one or more of: a position of the sensed coded data portion, a position of the sensing device relative to the interface surface, an orientation of the sensed coded data, or an orientation of the sensing device relative to the interface surface. Furthermore, the indicating data is transferred to a computer system being responsive to the indicating data to determine the orientation of the object.