To Serve CAD

Now and then I come across something that is for lack of a better description just kind of cool. I am not sure if it is practical. Just because you can do something doesn’t necessarily mean you should do something. With that disclaimer… let me share with you something cool. Stay with me because this is a little bit “out there”.

I have AutoCAD, ArcGIS Desktop, ArcGIS Server, and ArcGIS for AutoCAD on my laptop. Doesn’t everyone? See the sign post up ahead…? In the twilight zone everyone does. (My apologies to those reading this in another culture and language, and not familiar with the obscure TV references.)

ArcGIS desktop reads AutoCAD and Microstation files directly. If my AutoCAD file contains feature classes according to the mapping specification for drawings, then I can use those feature classes directly and without conversion as layers in an ArcMap map. I can symbolize the resultant features thematically according to the user defined values that they hold. I can color polygons based off of specific values, or vary the thickness of lines based on a range of attribute values, or use different point symbols… etc. I can also use the attribute values to create text labels that ArcMap knows how to place nicely.

I can serve ArcMap maps that I create as a map services using ArcGIS Server. I can use ArcGIS for AutoCAD to consume map services from ArcGIS Server including maps that reference AutoCAD drawings. In ArcGIS for AutoCAD I can edit AutoCAD entities as well as modify entities according to the mapping specification for drawings. Now it starts to get interesting.

ArcGIS Server map services can be cached or they can be dynamic. Dynamic map services are drawn by ArcGIS Server directly from the data referenced by the map document that is being served. If I open the AutoCAD drawing with ArcGIS for AutoCAD that is referenced by the ArcGIS map document, that is in turn being served by ArcGIS Server, and I use ArcGIS for AutoCAD to connect to that Map Service of the AutoCAD file that I am in… stay with me. ...Then when I make a change to the AutoCAD drawing, such as changing a feature class attribute and save the file and refresh the map service, then I see the map that is thematically drawn by ArcGIS Server which is based on the features and user defined attributes of the AutoCAD entities from the AutoCAD drawing that I am in! ...Whew!

Ok, I’ll wait while you re-read the paragraph above… So, I can use ArcGIS Server to do thematic mapping of my AutoCAD data via a map service while I’m in the same AutoCAD file as long as I save the file before I refresh the map service, and as long as ArcGIS Server and ArcGIS for AutoCAD have access to the same AutoCAD file, and the schema of the AutoCAD file doesn’t change. Granted, this is an extreme use of ArcGIS Server, but it is, I think, an interesting exploration of GIS and CAD interoperability, pieces of which you may find useful.

In light of this blog post the roasted vegetarian from the previous post is even more disturbing.