Serial port and GPS

OsmDldForm Class

Form controling downloads from openstreetmap.org

For a list of all members of this type, see OsmDldForm Members.

System.Object
   System.MarshalByRefObject
      System.ComponentModel.Component
         System.Windows.Forms.Control
            System.Windows.Forms.ScrollableControl
               System.Windows.Forms.ContainerControl
                  System.Windows.Forms.Form
                     serial.FormWithInvoke
                        serial.OsmDldForm

[Visual Basic]
Public Class OsmDldForm
    Inherits FormWithInvoke
[C#]
public class OsmDldForm : FormWithInvoke

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Remarks

A GUI based programm for downloading maps from www.openstreetmap.org. This GUI replacement of the command line tool osm.exe can be called from the applications map.exe and sgps.exe. The meaning of the text or combo fields is very similar to the command line options in osm.exe described in the class OsmDldTest. The inputs in the form have in particular the following meaning:

Basename, string Basename for the exported map files. The export creates then a file called str.map and a number of files with names str<num>.png, .jpeg or .osm. Also paths can be used, eg. /tmp/mytown, the directories named in the path must exist.
Exporter, string Defines the exporter to use for creating the resulting maps. Currently the web service www.openstreetmap.org supports only the following exporters: osm, mapnik and osmarender, so that the value of this parameter may be one of these three strings. The exporter osm causes creation of osm-files beeing an openstreetmap specific XML description of the map. mapnik and osmarender produce png or jpeg bitmaps. Currently only these bitmap formats are supported in the classes BmpMap and BmpMaps. The service www.openstreetmap.org is very sensitive, especially the mapnik exporter is often unavailable, unfortunately it seems to produce more accurate maps that the exporter osmarender. The exporters have also numerous limitations regarding the size of the resulting bitmaps and size of the exported area, so that values of -steplat, -steplon, -scale and -osmarender_zoom have to be found, by which the service www.openstreetmap.org works at all.
Export format, string Format of the bitmap files exported by the exporter, currently png or jpeg.
Min. latitude, number Minimum latitude of the whole area to download. Format of the number according to Utils.coord2dec(), this means either a floating point number with a dot as decimal separator or a number with degrees, minutes, seconds, eg. 12d34m45.678sE for 12 degrees, 34 minutes and 45.678 seconds East.
Max. latitude, number Maximum latitude of the whole area to download. Number format according to Utils.coord2dec().
Min. longitude, number Minimum longitude of the whole area to download. Number format according to Utils.coord2dec().
Max. longitude, number Maximum longitude of the whole area to download. Number format according to Utils.coord2dec().
Step latitude, number The whole area is subdivided into small rectangles. This is the step for subdividing the latitude part. This value must be > 0. For example for -minlat=48.0, -maxlat=48.05 and -steplat=0.03 the southern edges of the resulting rectagles will be at 48.0 and 48.03 incl. and the northern edges wii be located at 48.03 and 48.06 excl.
Step longitude, number The step for subdividing the longitude part.
Scale, integer Mapnik scale. No idea, how to compute it, usually values about 54500 give good results. Mapnik export does not work for wrong scales and it usually ends with a cryptic error message. In doubt try to export data from the interactive service on http://www.openstreetmap.org and try to find a working value there. This value is considered only for the exporter mapnik.
Osmarender zoom Zoom for the osmarender exporter, considered only for osmarender. Exports resulting in height/width > 2000 pixels don't work so the values of zoom, steplat and steplon has to selected carefully. In doubt try the interactive service first.
Using the menu item Map/download the download of the map files can be started. The status of the download is shown in the tabular control on the bottom of the window. The column No. contains the sequential number of the downloaded map file. The column Status is empty if the download of the file succeeded, else it contains the error message delivered by the web server of OpenStreetMap. The columns Min./Max. latitude/longitude contain the minimum and maximum coordinates of the single rectangle downloaded into one file.

Example

Basename test1
Min. latitude 48.06
Max. latitude 48.22
Min. longitude 11.43
Max. longitude 11.43
Step latitude 0.04
Step longitude 0.08
Exporter osmarender
Osmarender zoom 15
Export format jpeg
causes download of files test10.jpeg ... test115.jpeg containing the area from 11.63E 48.1N to 11.75E 48.18N. Each of the files contains contains a rectangle with 0.08 degree width (longitude) and 0.04 height (latitude). Additionally it creates the map file test1.map describing, which rectangle is included in which bitmap file. The path to this map file can be given as parameter to the class BmpMaps in applications map.exe or sgps.exe, which will show the requested position within one of the downloaded bitmap file. The bitmap files are created using the exporter osmarender with the osmarender zoom of 15, what results with bitmap sizes of 1864x1395 pixels.

Requirements

Namespace: serial

Assembly: map (in map.exe)

See Also

OsmDldForm Members | serial Namespace