Specifying georeferencing and geolocation
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Command |
Path |
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Geolocation |
File > Document Settings |
The goal of working with a georeferenced drawing in Vectorworks is to align the drawing’s internal origin, and therefore its geometry, with a specific location on Earth. Georeferencing options are complex; what works for architectural workflows may not be suitable for a planning workflow. Additionally, different regions of the Earth have different geographical requirements. Since the earth is not a perfect sphere, it is not a straightforward process to correlate the Earth’s three-dimensional surface with a two-dimensional map. Coordinate systems use mathematical formulas to translate the shape of the earth onto a 2D page. Because there is always a slight error during translation, different coordinate systems are preferable for different regions of the globe.
A proper coordinate reference system (CRS) has a big impact on distance measurements. It's important to select the correct CRS for the project's location, because then you can trust the measurements from the map.
A file is geolocated when when a coordinate system is selected (georeferencing) and, in addition, a survey point has been placed.
The Geolocation dialog box specifies the CRS and selects the basemap to display, if any. Then, you can use it to place the survey point if geolocation is also desired, which is typical.
The easiest way to georeference and geolocate the file is with the Geolocation Setup Wizard. Click the Survey Point tool to access the wizard. The wizard provides all of the information and assists you with the proper selections based on your project.
To set a coordinate system and basemap display options:
Select the command.
The Geolocation dialog box opens.
Click to show/hide the parameters.Click to show/hide the parameters.
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Parameter |
Description |
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Geolocation |
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Create Survey Point |
If the file does not yet contain a survey point, this places the survey point on the active design layer at the next click, and opens the Survey Point Setup dialog box for setting the geolocation parameters; see Survey point settings |
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Survey Point Coordinates |
If the file contains a survey point, displays the survey point's coordinate information and angle from true north. The design layer location of the survey point displays. |
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Locate the Survey Point |
Navigates to and zooms to display the survey point |
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Delete the Survey Point |
Deletes the survey point, meaning that the file is no longer geolocated |
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Coordinate Reference System (CRS) |
Displays the selected CRS |
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EPSG |
Displays the EPSG code of the currently selected coordinate system; click the link for more information online |
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CRS Name |
Displays the name of the currently selected coordinate system |
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Units |
Displays the units of the currently selected coordinate system |
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Select CRS |
Selects the georeferencing coordinate system, as described below. If there is an existing survey point in the drawing, it is associated with the CRS, and these settings are not enabled. If you need to make a change, you can delete the existing survey point and place a new one, or edit the survey point's CRS from the settings in the Object Info palette. |
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Basemap |
After selecting a suitable CRS, you can display a background map of the geographical area specified by the CRS. The basemap is a live map that displays on all design layers. The map is associated with a specific provider (internet access is required). In some simple cases, you may only need to specify the coordinate system and display a regional basemap behind the design layers. Using the Geolocation Setup Wizard is the best way to choose a suitable CRS and enable the basemap, if you are not an expert. This avoids a situation where the project is far away from the internal origin. The basemap is different from the geoimage, placed with the Geoimage tool. That is a static object. |
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Show basemap behind the design layers |
Displays the basemap; you can also toggle the display from the Quick Preferences with Show Basemap |
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Service Provider |
Select the service for the basemap display. Google Maps (subscription or Vectorworks Service Select benefits required), and Open Street Map (OSM, a community-based site for map data operated by the OpenStreetMap Foundation) are free services. ArcGIS Portal may require a login. |
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Select map type (Google Maps) |
Select road map or satellite view |
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Detail Level |
Select the level of detail for the map, which is downloaded in "tiles." Auto is recommended, but you can select More for more detail, although this will be slower, or Less for faster tile download. |
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Select Service (ArcGIS Portal) |
See Using a map service for information on selecting the service for ArcGIS Portal |
Specify the georeferencing parameters. Click Select CRS to choose the coordinate reference system.
The Select CRS dialog box opens.
Select the correct CRS for the project's location. There may be several acceptable CRS for a particular area. If you're not collaborating with others, you can use any of these. If you're exchanging drawings and georeferencing is important, the workflow is simpler if everyone uses the same CRS.
Click to show/hide the parametersClick to show/hide the parameters.
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Parameter |
Description |
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Select CRS |
Select whether to specify the CRS with the EPSG code, by entering Well Known Text, or by WGS 84/Pseudo-Mercator. EPSG: Normally, you should select a coordinate system from the CRS list, which displays by EPSG code, a unique numeric code originally developed by the International Association of Oil and Gas Producers. Well Known Text: If you are an advanced user and you have a Well Known Text (WKT) definition, you can paste it. The WKT markup language is supported by GDAL (Geospatial Data Abstraction Library). Once you have selected a CRS, you can see its WKT markup here. WGS 84 / Pseudo-Mercator for worldwide use: WGS 84 / Pseudo-Mercator is a global coordinate system that is not recommended. Distortion can reduce accuracy when matching the Vectorworks distances and the map distances. If possible, select a more regionally-specific coordinate system or convert to a suitable CRS. |
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Filter |
Filters the CRS list by showing only those names that contain the filter keyword |
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Show CRS list |
Filters the CRS list by the recently used CRSs, or shows all CRS |
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Hide deprecated CRSs |
Removes older, deprecated systems from the list |
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CRS list |
Displays the EPSG code and CRS Name; click one to display its information and see the extents on a map, and to select it |
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Selected CRS Extents |
Displays a preview map of the area defined by the CRS |
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Zoom |
Click + to zoom into the map, or - to zoom out |
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EPSG code information |
Displays the selected CRS information, including its Well Known Text (WKT) |
Once you have selected the CRS, click OK to return to the Geolocation dialog box.
The selected EPSG code and code name displays. If desired, click on the link in the code to go to an external website with additional information about the CRS code.
You can enable the display of a basemap of the geographical area. This background map displays behind the design layers and adjusts to any different design layer scales. It can be toggled on and off from the Show Basemap Quick Preference, or by re-accessing the Geolocation dialog box and selecting or deselecting the check box.
Place the survey point to geolocate the file. For more information, see Adding a survey point.
