DWG format
Koordinates supports the export of vector, raster and point cloud data, including aerial photography, into DWG, a proprietary format used in a range of CAD software applications. This makes it easier for CAD users to use authoritative spatial data as a reference layer in their projects.
Raster exports
Section titled “Raster exports”While DWG is a vector-based format, we enable the export of raster images, such as aerial photography, to DWG. We do this by inserting polygons within the DWG file, which then link to external JPEGs of aerial photography. The CAD software effectively ‘fills’ those polygons with the JPEG image files — enabling large aerial photography to be used in CAD software without crashing the application.
Vector exports
Section titled “Vector exports”Points, lines and polygons for vector exports are inserted directly into the DWG file, though note that there is a maximum of 50 MB vector data allowed per DWG. This is to ensure that your DWG file does not crash your CAD software.
In the export options for a vector dataset, under DWG Export Options, you can choose:
- Insert GIS attributes as XData: attaches each feature’s attributes to it as XDATA.
- Polygons filled with a hatch pattern: fills polygons with a hatch (polygon datasets only).
Point cloud exports
Section titled “Point cloud exports”Point clouds export as DWG with RCS: the DWG file links to a ReCap RCS point cloud file, which Autodesk software can open.
Tabular data
Section titled “Tabular data”We do not support export of tabular data to DWG. If you have added tabular data to your collection, it will be filtered out before export.
Projections
Section titled “Projections”Because CAD software does not tend to support projections, Koordinates ensures that your DWG export is laid out as close to your chosen projection as possible. Note that coordinate reference information is not included in your DWG export.
Layering
Section titled “Layering”DWG files downloaded from Koordinates contain all the vector and image layers you’ve selected, overlaid and positioned correctly relative to each other. The order of these data layers in your DWG export will follow the order of data layers in your collection.
‘Z’ coordinates
Section titled “‘Z’ coordinates”Koordinates supports the use of ‘z’ coordinates for DWG exports, though note that the z unit must match that used for the x and y axis for use in CAD software. This is not always the case with geospatial data, especially layers that use latitude and longitude as units (because there is no ‘z’ equivalent for latitude and longitude).
To ensure that CAD software can process data with z coordinates, Koordinates will automatically set the units of DWG exports to metres or ‘undefined’, depending on the chosen export projection.
Limitations
Section titled “Limitations”Note that, for DWG downloads, Koordinates does not support:
- Map projection or coordinate reference system information;
- TIFF as an image format;
- Grid layers; and
- Export of symbology.