Drawing window coordinate system

Digi3D 2011 allows us to specify the projection in which the vectors will be displayed in the drawing window. To do this, we have the field Horizontal coordinate system of the drawing window, in the dialog box New project, in the Drawing file tab. The coordinate system that we select will indicate the projection that the program will use to show the vectors in the drawing window. If we press the three dots button, the dialog box Horizontal coordinate system of the drawing window will appear that will allow us on the one hand to indicate that we want the drawing window to inherit the horizontal coordinate system of the first file loaded and on the other hand will allow us to select a reference coordinate system of those we have previously memorized. If we do not have any memorized, we can always locate one among those listed in the database EPSG (included with the installation of the program) by pressing the Buscar... button and then on Memory or paste a string Well Known Text in the field enabled for it and press the Memory button. We can select both projected and geographic coordinate systems. Each coordinate system has associated units, so if we select the projected coordinate system NAD27 / Alaska Albers the work units shall be American feet, and if we select ETRS89 / UTM Zone 30N the working units shall be meters. If we select a geographic reference coordinate system, the program will use the Plate Carrée projection, which basically consists of converting the earth into a plane in which the longitudes grow to the west (taking as origin the Greenwich meridian) and the latitudes to the north (taking as origin the equator). The units in the geographic coordinate systems are angular, so that the coordinates that we will display will be Latitude/Longitude in most geographic coordinate systems. If we make measurements Digi3D 2011 will try as far as possible to calculate them in meters using the Sodano method (inverse problem of geodesy) for distances or using a stereographic projection with center in the center of the entity and projecting the entity on that plane for area calculations. In this case the units will always be meters. Despite its limitations (imprecise measurements and areas) it is possible that we are forced to select a geographic coordinate reference system for the drawing window because certain importers, such as the Web Map Service importer or the orthophoto importer, only allow us to upload files if the drawing window is in a coordinate reference system compatible with that of the drawing file to be loaded. There are many Web Map Service servers that only publish information in the geographic coordinate reference system WGS84, so if we want to connect with these servers we will have to select WGS84 as horizontal coordinate system for the drawing window. Finally, if we want to know the reference coordinate system assigned to the drawing window (whether we have indicated it implicitly or if it has been inherited from the loaded drawing file) we can click on the button that follows the coordinates in the toolbar Coordinates. Below is a video showing this functionality