Map 3D 2009: Multiple Surfaces and 'gaps'
I was recently working with a client who was generating Map 3D surfaces from a SHP point file DEM. These SHP files were based on the Canadian NTS sheets, and as such it took 4 sheets to cover the area they were working with. There was a problem once all of the raster surfaces were put together.
As you can see from the image, there were resulting ‘gaps’ between the 4 surfaces. This is likely happening because the dem points do not form a uniform boundary at the edges defined by the NTS sheets.
So, how can we resolve this? I thought what if we could merge the 4 separate SHP files into a single SHP file? How might I do this without any Arc* tools? I suppose one option would be to import all of the SHP files into Map, and then export them out as a single SHP file. But… that’s too much work, and the datasets might be too big to bring all of this into Map.
So, off to trusty ‘ol Google and search for some information on merging SHP files. Well, wasn’t I surprised when one of the first hits was pointing to a Nabble discussion and one of the replies pointed to the GDAL/OGR site and ogr2ogr tool, and FWTools (Frank Warmerdam: a name followers of the MapGuide User list would recognize) I had used the OGR FDO Provider for accessing MapInfo TAB files, but hadn’t looked at it much beyond that. After some quick reading I found there is a lot of useful functionality built into the library! So I created a quick batch file to process the SHP files, re-created the 3D Surface in Map, and Voila! We have a nice continuous surface across the NTS sheets.
Take care,
Warren
AU in 56 days
Comments
I'm having problems in Map 2009 when I try to merge polygons(sdf).When i merge smalls polygons its works well.But when I try to merge big polygons,its didn`t work.Seems like a bug....Cause the Map 3D just keep processing till get instability.So I`ve to finish the appIication in the windows task manager.I work in workstation with 16 Gigas, couldn`t be a memory problem.I tried to repair the installation,reinstall and change to other PC.The same error.Does anyone saw a report like this?
I'm checking the features after few merges.I'm merging two polygons and so checking before merge more.But still doesn't work.
The user temp you refer is Windows/temp? But now something strange is happening.The software is crashing with small polygons too.
I cleaned up my temp folder and still doesn't work.
__________________
Dilson Zititi Kitoko
GIS Analyst
+55(24) 2103-0331
dkitoko@ctallen.com.br
I apologize, I was sure I had replied to this a couple days ago, but just came back and saw that my reply was not there...
Regardless, I would like to try to replicate this. Is this data that I could see, or is it sensitive information? or is it too big to be emailing around?
Even a smaller sample that is causing the problems would be beneficial. You could email it to: wmedernach@gmail.com
Thanks