Cartographic Generalization of the River Network Including Standards of the Objects Recognition

Digital cartographic generalization is one of the basic issues currently implemented by the National Map Agencies. The commonly used generalization methods are based on procedures for processing spatial databases where the DLM and/or the DCM are stored. The authors have proposed new solutions for large-and small-scale maps generalization on the example of river network objects. The first stage of process takes into account the hierarchy of watercourses resulting from the Map of Hydrographic Division of Poland (MPHP). The condition of entire watercourse recognition is checked iteratively considering the changing topology. In the second stage, scaledriven generalization (simplification) is carried out, taking into account the width of the symbol. Data used in the article are: General Geographic Database (BDOO) (reference scale 1:250k) and MPHP database (reference scale 1:50k). The obtained results were compared with the BDOO as well as visually in relation to other maps.