1. A graphical user interface comprising: an editing window; means for enabling a user to interactively edit in the editing window one or more tansformation hierarchies including one or more geometrical transformation operators employing mathematical matrices, wherein a transformation operator provides transformation data as an output, wherein the output transformation data does not include image data; means for enabling a user to interactively edit in the editing window one or more effects trees including effects operators, wherein at least one effect operator in the effect tree has one or more inputs for receiving transformation data and has a local transformation specification that is combined with the received transformation data; and means for enabling a user to connect an output of a transformation operator to an input of an effect operator for receiving the transformation data; a display operable to present the editing window including both the one or more transformation hierarchies and the one or more effects trees to the user.