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

MapGuide Enterprise 2011

MapGuide Enterprise 2011 is now shipping.  I’ve been waiting for this release for some time now, as it is supposed to address some key components of the the MapGuide framework.  Of particular note for me is Fusion, or the Flexible WebLayout, which is supposed to be ‘much less buggy’, and more complete with additional out-of-the-box functionality including redlining, querying, and Theme tool. 

 

 

Fusion offers a much more pleasing UI experience for the user, however, with previous versions of the Fusion Layout, I just wasn’t comfortable implementing this into a client production environment.  With some ‘hacks’ and workarounds you could definitely get it functioning, but I just didn’t feel it was ready for prime time.  Time will tell if that’s changed.

 

As for the new tools, it’s exciting to functionality like this out-of-the-box:

Query Features

The new Query Features tool is essentially an ad-hoc query tool to query/filter any layer based on a property of that layer, and/or a spatial query.  The maximum results can be limited, and the queried features can be selected, and zoomed to through the UI.

A nice feature with this tool is that you can query a specific property, but then choose what prpoerty to output.  So maybe you want to look for all rooms that have a department code of ‘Pharmacy’, but you want to be able to see the resulting room number instead of a bunch of records returned with ‘Pharmacy’ as the return value.

 

 

 

Digitizing/Redlining

The Digitizing tool allows you to create points, lines, rectangles, and polygons.  The functionality actually takes advatage of one of the Open Source libraries MapGuide is built upon called OpenLayers.

OpenLayers is a JavaScript library for displaying map data in most modern web browsers, with no server-side dependencies

The layer that the objects reside on can be renamed, and the digitized objects themselves can be renamed and removed.  The digitized objects can also be saved out to a file in a standard GML format.

Currently, the default style of the markup objects is controlled in the Widget JavaScript file

 

 Theme

The Theme Tool allows you to build a theme on any layer in the map, on the fly.  In my test I performed a simple 6 rule theme by area of rooms.  The themed layer was created extremely fast!  However, the layer did not show up in the Legend.  I’ll need to look into this further to determine the cause.

 

 

 

 

 

 

That’s for now, so unitl next time,
Take care

Warren M

MapGuide Open Source 2.2 Beta is released

For those following the MGOS developments you might be interested in the latest 2.2 beta that has been posted to the OSGeo MapGuide site.  I did see a couple API items that have changed and could affect existing code, so be sure to check the release notes for major changes.

Until next time,
Take care

Warren M