GenesisIV Tutorial: Importing Data from MapInfo

For demonstration we'll just use a landscape with a heightfield already defined and we'll import data from a MIF file containing roads - qroads.mif, which contains polyline data. The first step after loading the heightfield is to add a new layers surface layer - Roads - to contain the roads vector data.

Next we open the Landscape Definition module and from the Edit menu select Georeferencing. It is essential that georeferencing coordinates are correctly set up before importing data. Here we have entered suitable coordinates into the left hand box (labelled Georeferencing). Click OK to confirm.

With the georeferenced coordinates set up for the landscape open the MapInfo MIF import plugin from the plugins menu. This images shows the plugin dialog after locating the roads MIF file using the elipsis (...) button against the MapInfo MIF edit box. Note that the plugin scans the file and automatically returns the bounds coordinates for the data to be imported. This should match up with the georeferencng coordinates previously entered (and shown here for convenience in the Landscape Grid Coordinates box).

Other important data items to note in this dialog are:

• Read Bounds Clause: Reads the MapInfo bounds clause instead of scanning the file
• Use Layers: The layer into which the MIF file data will be imported. Select from the drop down list
• Select: Allows filtering by attribute. In this case we'll take the default - Select All.
• Object Type: Displays the type of data to be imported from the file. This is not set automatically, so it is important that the correct type is set. For this example we will read Linear features - Lines and Polylines. Other options cover polygons and points.
• Value: Filter value if filtering by attribute.
• Point Space Tolerance. Points closer than the value will be merged - this throws away unneccessarily fine data which would not be shown because of fractalization uncertainty when rendering. If your import has a great many points you may want to increase this value - up to 10 times the default (calculated by GenesisIV) will not have too much of an effect on the final image.

When done click Import - the data is imported, with the current object number shown in the Importing box. When finished this shows complete. The data is not shown on the landscape until the plugin is closed.

Here the road data ys shown the grey lines (the colour selected when setting up the layer). Once imported vector data can be edited in the usual way.