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"Geographic location information in a drawing file is built around an entity known as the geographic marker. ... Typically a geographic location is defined by its coordinates (for example, latitude, longitude, and elevation) and the coordinate system"
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Inserting geographic location information to a drawing file makes points within the drawing correspond to geographic locations on the surface of the Earth.
Geographic location information in a drawing file is built around an entity known as the geographic marker. The geographic marker points to a reference point in model space that corresponds to a location on the surface of the earth of known latitude and longitude. The program also captures the direction of the north at this location. Based on this information the program can derive the geographic coordinates of all other points in the drawing file.
Typically a geographic location is defined by its coordinates (for example, latitude, longitude, and elevation) and the coordinate system (for example, WGS 84) used to define the coordinates. Moreover, the coordinates of a location can differ from one GIS coordinate system to another. Hence, when you specify the geographic location of the geographic marker, the system also captures the details of the GIS coordinate system.
Typically CAD drawings are unitless and are drawn at 1:1 scale. You are free to decide the linear unit a drawing unit represents. GIS systems, on the other hand, allow the coordinate system to decide the linear units. In order to map CAD coordinates to GIS coordinates, the system needs to interpret CAD drawing units in terms of linear units. The system uses the setting stored in the INSUNITS system variable as the default linear measurement of a drawing unit. However, when you insert geographic location information, you have the option of specifying a different linear measurement (for a drawing unit).
After you insert a geographic marker in a drawing, you can:
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To makes points within the drawing correspond to geographic locations on the surface .Geographic location information in a drawing file is built around an entity known as the geographic marker. The geographic marker points to a reference point in model space that corresponds to a location on the surface of the earth of known latitude and longitude. The program also captures the direction of the north at this location. Based on this information the program can derive the geographic coordinates of all other points in the drawing file
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Assigns geographic location information to a drawing file.
You assign a geographic location by specifying the latitude and longitude of a known location and marking the corresponding position in model space. You can also override the default GIS coordinate system relative to which the latitude and longitude are specified.
The following prompts are displayed.
Map FindDisplays a dialog box containing a map, if you are signed in to Autodesk A360. Pick a location from the map. If you are not signed in to A360, you can only specify the latitude, longitude, and elevation.File FindDisplays a standard file open dialog box to enable you to select a *.kml (keyhole markup language) or *.kmz (compressed KML) file. The program extracts the first place mark specified in the file you select.Select a pointSpecifies the point in model space that corresponds to the geographic location you specify in the dialog box. The command places a zoom invariant indicator known as the geographic marker at the point you specify.Specify north angle directionSpecifies the direction of the north as an angular deviation from the X axis on the World Coordinate System (WCS). By default, the north is the positive Y direction.
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