IMAGINiT Geospatial Solutions Blog

AutoCAD Map 3D – Generating Contours from DEMs

AutoCAD Map 3D has a great function included that can generate contours from a DEM.   Simply right Clicking on a DEM layer in the Display Manger you will see a command to 'Create Contour layer’.  The resulting contour layer will be a new SDF file.

This command will bring up a dialog box that allows you to specify the parameters of the Contour Layer:  the Layer name for the Display Manager, the contour major and minor intervals, and the resulting SDF file location.

Once the Contours are generated, one would expect to be able to use the Data Table to view the individual contours and related data.  Well, one would be wrong…  as there seems to be an ‘undocumented feature’ (re: bug) where the data table does NOT display the contour data.

As you can see from this screen capture, only a single record is displayed in the Data Table.

To be able to see all of the contour records, you need to drill-down into the Feature Class and select the Contour Class:

Once you choose the Contour Class you will then see all of the records displayed in the Data Table:

*** NOTE ***
There is one caveat to this…  Even though you can ‘see’ the records, you can ‘zoom to a contour’ by selecting the record in the Data Table, or ‘zoom to the record’ by selecting a contour in the map.

Until next time,
Take care

Warren M

Working with MapInfo data from AutoCAD Map 3D

My colleagues, and good folks from down under, have identified that they have a requirement to be able to integrate and work more efficiently with MapInfo data.  It seems MapInfo is a widely used data format in many organizations throughout Australia.

Now, AutoCAD Map has long been able to Import and Export MapInfo mif/mid files, and in recent versions, .tab files.  But, besides the fact that we are creating a new silo of data, or another copy of the data, we also know that import and export processes are never 100% complete.

So what are our options then for working with MapInfo data in AutoCAD Map 3D? 
I don’t see an ‘Add MapInfo Connection’ in my AutoCAD Map 3D?

Well, thanks to the FDO Open Source community, there is an open source FDO provider called OGR.  The OGR Provider provides read/write access to dozens of vector formats, including MapInfo.

To implement this functioning in AutoCAD Map (and MapGuide for that matter) you must first download the provider, and then install and configure it for your application: AutoCAD Map 3D, or MapGuide.  The Provider downloads can be found here.  Simply choose the link for the FDO version you are currently using, and download the appropriate provider.

Let’s use my install of AutoCAD Map 3D 2010 as an example:

Download the Windows Binary OGR Provider for the 3.4.1 version of the FDO Providers.  The zip file will contain the OGRProvider.dll file.  Ensure tht AutoCAD Map is not running and move the OGRProvider.dll into the following folder:

C:\Program Files\AutoCAD Map 3D 2010\FDO\bin

Next, the Providers.xml file, in the same folder, needs to be modified by adding the following snippet:

<FeatureProvider>
  <Name>OSGeo.OGR.3.4</Name>
  <DisplayName>OSGeo FDO Provider for OGR </DisplayName>
  <Description>OGR Provider</Description>
  <IsManaged>False</IsManaged>
  <Version>3.4.0.0</Version>
  <FeatureDataObjectsVersion>3.4.0.0</FeatureDataObjectsVersion>
  <LibraryPath>OGRProvider.dll</LibraryPath>
</FeatureProvider>

Restart AutoCAD Map 3D and you should see the new OGR provider listed in the Data Connect window.

Simply provide the path and filename of the MapInfo file you wish to connect to, click Connect:

Then Add To Map.

And you should be off and running…

*** Caveat ***
Updating of files is NOT currently supported.
IOW, files can only be accessed in READ-ONLY mode. 

*** Potential Workaround ***
So, if you need to be able to actually edit the data, one workaround might be to Bulk Copy the data to another FDO Feature Source like: SDF, SHP, etc.

I know, I know, I’m contradicting what I said earlier about avoiding ‘creating data silos’…  Unfortunately, we’re not living in a perfect world… Yet… 

I hope you’ve found this helpful, and if you have any questions or comments on this or other items, don’t hesitate to drop me a note.

Until next time,
Take care

Warren M