A method of manipulating a vector graphics data file representative of at least one graphics element defined by a set of co-ordinate values in a graphics image, the method comprising the step of scaling down the at least one graphics element by applying a scaling factor to the set of co-ordinate values defining the at least one graphics element. One end of the stack is secured to one end of the housing. For example, the environment variable can be used to identify a particular location as being a user’s living room, kitchen, etc.