The main focus of this contribution is the description of mechanisms for an intuitive input of user-data with a direct response to gain fast parameter selection. To build polymorph i input methods for different parameters classes, a database containing knowledge about each operator is needed. This information about the syntactical and semantical structure is used to create adequate dialog elements, like sliders, list boxes, text fields, etc., each one responsible for a distinct parameter class. In addition higher-level semantics are used to aggregate data types, e.g., the user can draw a rectangle interactively, instead of only inputting the coordinates of its corners. Depending on the context, the user can also change certain subsets of the knowledge about the operator to fit special needs. Incremental computation of the results of an operator by successively expanding regions of interest is used to gain direct feedback for every change of parameter values. So by dragging a slider for the size of a smoothing mask, e.g., the user can see the effect directly and thus select the desired value rapidly. This approach is extended to sequences of operators. In this case, more than one parameters form will be open at the same time, one for each relevant operator, to have full control of all important values.