A method for generating model data of a plant having at least one sub-part involves: providing at least one respective diagram of an HMI interface for a respective sub-part, which contains topology information thereof; transferring the respective diagram, if necessary, into a computer readable form; importing the respective transferred diagram into a data storage of a computer and preferably automatically extracting model data of the respective sub-part therefrom, wherein the model data describe at least in part the topology of the respective sub-part; and providing the model data to an interface of the computer, wherein extracting model data from a diagram involves: detection of plant objects; and detection of plant object connections.