Forming coordinate of height at objects of hydrography |
Electronic map is intended not only for authentic visualization of data, but also for analysis of the data having spatial distribution. The screen of computer has only flat coordinates (x, y), and real objects of district can be described by means of three-dimensional representation (x, y, h). The computer GIS analysis allows to execute the modelling of district on the basis of the full coordinate description, but for this purpose it is necessary to execute preparation of a map for modelling. Forming coordinate of height at objects of hydrography program is intended for processing objects of electronic map, having "absolute height" characteristics with the purpose of formation at objects of hydrography of the third coordinate (H). As a result of the task execution the user map onto all works region, containing objects of hydrography with coordinate description X, Y, H is formed. Source data for Forming coordinate of height at objects of hydrography task is the electronic map created in view of requirements, shown to this kind of maps. The map should contain objects of hydrography, shore lines, land relief, nodal points of area hydrography and relief. Objects to which coordinate H will be appropriated, are set through the Filter, these are all kinds of the rivers (area, linear, drying up), except for the underground rivers, lake, a water basin and the microform (gullies, hollows, ravines). Objects for which in the classifier the presence of the semantic characteristic "absolute height" is stipulated, are processed in any case (it is set in the filter or not), the calculated value of height is given to each point of object. If the semantic characteristic is not specified, the object will be processed as the area river. Target data of the task is the user map with the objects of hydrography having the third coordinate H. The task is carried out by HIDROXYH.DLL module, which is called by means of the Run Application menu. After an applied task a dialog box of the task will appear. Target user map element of dialog displays a name of a target user map. Press the button "…" to change a map name. Objects of hydrography element of dialog displays quantity of processed sheets and objects. Elements of dialog: Line of water-current, Area objects with an inclination, Area objects with a constant level are marked on the user map by a code 31420000 underground rivers by default. Press the button "…" to change a code. Tolerance by a report of objects on a frame of adjacent sheets edited field sets the tolerance of a map in mm. Number of cycles of interpolation edited field sets the number of repeated interpolation of objects, in view of the heights calculated on the previous interpolation. Processing state element of dialog displays a status of processing of source objects and objects of the user map. The user should choose the list of objects to which it is necessary to give Н coordinate, having pressed the Filter button. Process of processing of the information begins after pressing the Ok button. It is possible to interrupt process of processing, having pressed for this purpose the Interrupt button. |