B. V. Kuchin, A. V. Pruglo, S. S. Ravdin

In the paper the problem of development of geoinformational system with following properties is considered: geoinformation system should be open-source to ensure safety and security of the data which is passed to geoinformational system; geoinformational system should be cross-platform and should work in both certified and non-certified operational systems while being used for different tasks; urge of compatibility with certified operational systems poses limitation for programming libraries and modules which are used in the system -- libraries and modules should be of the certified versions; geographical objects should be named in Russian language. Different approaches to the given problems are described and decisions taken into the final version of the geoinformational system are justified. Algorithm descriptions from the final implementation of described geoinformational systems are provided including data preparation algorithms (contours and altitude maps), map drawing algorithms (land-water mask calculation and map coloring), performance optimizations, translation of names of cities.