GEdraw

       Command line: GEdraw

           Description: draw polygons, paths and points in Google Earth using a TransLT transformation model

       TopoLT toolbar:

           Menu: TopoLT » Useful » Draw in Google Earth

Using this command you can draw in Google Earth polygons (closed polylines), paths (opened polylines) and points. The conversion of coordinates from projection system into geographic coordinates on WGS84 or ETRS89 (GRS80) ellipsoid, Greenwich Prime Meridian, is made according to the selected transformation model what is defined in TopoCfg – Transformations Section.

To draw in Google Earth you have to comply with the following conditions:

1. To have installed on this computer Google Earth software;

2. On the folder "Transformations" off the path where the program is installed you must have copied one or more transformation models generated by TransLT by which you can transform coordinates from drawing in geographical coordinates on one of the ellipsoids WGS84 or ETRS89 (GRS80), Greenwich Prime Meridian;

3. Select from Transformations section by using TopoCfg command the transformation model which has as initial coordinate system the coordinate system of the drawing and as final coordination system the geographic coordinate system on one of the ellipsoids WGS84 or ETRS89 (GRS80), Greenwich Prime Meridian;

4. Coordinates (x,y,z) from the drawing are read in the order (E,N,H) for coordinates from the projection system.

Entities that can be selected for drawing in Google Earth can be: 2D polylines (normal, fit or spline), 3D polylines, arcs, circles, ellipses or topographical points drawn with TopoLT.

For the polylines defined as parcels, using commands Detas, MDetas or Arr you may extract information regarding the parcel (parcel’s number and owner’s name). Area and length are calculated when applying this command and values are written according to the settings defined with command TopoCfg section Units.

Note: If in the drawing you have parcels defined with an earlier version than 10.0 you may restore the links between polyline (parcel) and texts using command RefLink.

After selecting the entities TransLT library is called to convert coordinates and to create the drawing in Google Earth.

Note: When you make the conversion of coordinates file, carefully select the transformation model because it has to do a conversion from the coordinates of projection system (coordinates from dwg drawing) into the geographic coordinates on WGS84 or ETRS89 (GRS80) ellipsoid. When selecting a time-dependent transformation model you will be asked to type the epoch t, in years with decimal, to calculate the dynamic coordinates.