Import ETAK / TeleAtlas MapBase files in .mbs or .xbs format. ETAK was a US digital mapping company acquired by Teleatlas, a Dutch digital mapping content company which in turn was acquired by Tom Tom, a Dutch company that provides traffic, navigation and mapping products. MapBase is a vector format primarily aimed at providing data for car and truck navigation.
To import from MBS format:
Choose File-Import from the main menu.
In the Import dialog browse to the folder containing data of interest.
Double-click the file ending in .mbs or .xbs for the data of interest.
All components from the .mbs file will be imported.
We can double-click on components that are created to view them. This particular .mbs file stores drawings of interest for navigation in a portion of San Francisco.
For a more interesting display, we first create a new data source using a Bing street maps image server as shown in the Example: An Imageserver Tutorial topic. We then create a map and drag and drop the Bing layer into the map, and then we drag and drop the sfo_ca Lines Drawing into the map.
Zooming into the drawing, we see that the street lines and outlines of the piers in the drawing do not align well with what Bing shows. The problem is that .mbs files may use the Latitude / Longitude coordinate system without specifying the datum. When imported as Latitude / Longitude the default assumption is WGS 84 datum is used. In this case, the sample .mbs file used NAD 27 and not WGS 84 datum.
Setting aside the irony that a mapping company eventually acquired by a GPS vendor, Tom Tom, would use anything other than WGS 84 for Latitude / Longitude, we can fix the problem by launching the Component pane, and then choosing Repair Initial Coordinate System in the coordinate system picker for the drawing layer.
We drill down into the Base Coordinate System dialog, where we choose North American 1927 (mean for CONUS) to choose that datum. We click OK and then click OK back up through the dialogs.
The result is precise alignment between the drawing imported from .mbs and the Bing layer.
Use Folders - Importing .mbs files can create many components. To keep those from being mixed into existing components in a project, first create a folder and then, with the focus on the folder (click the folder in the Project pane to highlight it), do the import. That will place all imported components into the folder.
NAD 27 ? - How did we know to use NAD 27? We used an Internet search engine, pouring through many pages of totally irrelevant web sites until we found an obscure reference that sometimes Mapbase files in the US use NAD 27 as a datum. An experienced GIS user might also notice the characteristic shift of data that is not quite in alignment with a "known good" (Bing) layer that indicates a wrong choice of datum. There are only a handful of datums that have been popular in North America for use with Latitude / Longitude, so trying each of them will quickly enough discover that NAD 27 is the right one. Manifold allows changing datums so rapidly that it is easy to check several.
Projects and .map Files