Most ESRI Shapefiles of contours are defined as flat polylines (at 0.0 elev) in the SHP file, and the user is expected to elevate the polylines using data defined in the accompanying DBF file. Here is a complete procedure using MapWorks to import these files with the polylines properly elevated.
Users of MapWorks/C3DTools 7.0 or higher see revision note below.
- Begin a new empty drawing with the proper template.
- Issue the MapWorks Map Import command (Tools Section).
- Make sure the toolbar button for “Add Available Data” is pressed.
- Click the “Add Files to List” button and select the file(s).
- Click the [OK] button to import the geometry.
- Zoom to the import content and inspect a polyline. You can click one and look in the PROPS dialog where it will show Elevation: [0.0]. If you have the MapWorks Extended Data Edit dialog open, the fields will be displayed allowing you to review for the elevation field (value equals proper elevation).
- Issue the MapWorks Extended Data Manager tool (Tools Section).
- Click on the “Require Existing XData” toggle (upper left).
- Click the [Select] button in the upper left and type ALL (then press enter).
- Find and select the appropriate field in the list (like DXF_ELEVAT).
- In the lower left Option: […] drop down, choose “Elevate By Value”.
- Click the adjacent checkmark button to process the objects.
- Close the dialog with the [X] in the upper right.
- Select a polyline again the elevation in PROPS should show properly.
This drawing is now ready to create a surface model, etc.
REVISED 07-21-2018: MapWorks/C3DTools now contain a PolyContour ShapeFile Read tool that reads the shapefile, sets elevations and optionally layers the generated results.