dwgdxffile formatsopen-source-gis
Which GIS support DXF and/or DWG (preferably read&write)?
Update: Are there any open source GIS supporting these or similar CAD files?
Support of CAD files generally seems to be problematic. What are the biggest issues/problems concerning DXF/DWG support in GIS?
You could use ArcGIS Explorer Online to create a free GIS web map. I believe you just have to create a global account with ESRI.
in qgis, you can see your dted files as contour map or hillshade map, if it helps.
for converting your file to contour:
Raster → Extraction → Contour
for converting it to hillshade:
Raster → Analysis → DEM (Terrain Models).
This examples from Paulina Fernandez Luengo which shows hillshade and contour map together.
i hope it helps you...
Best Answer
Problem with DWG and DXF formats is that Autodesk does not publish full specifications.
DXF Format
DXF ASCII format is well known and most of packages can read it.
Binary DXF is partially documented and since it is not primary AutoCAD format, it is rarely supported. For more details see here: AutoCAD DXF
DWG Format
DWG format is read by most GIS packages, but usually with some constraints.
Two most used libraries that can read and write DWG files are one that can be licensed from AutoDesk and other is from non profit consortium Open Design Alliance (ODA). AutoDesk library is limited for use in products that do not compete with AutoDesk products, while ODA library does not support all DWG features.
ODA library was catching up with changes introduced by AutoDesk until 2006 when AutoDesk sued ODA and some software vendors for copyright infringement. Lawsuit was settled earlier this year and result is that ODA library cannot write 100% compatible DWG files. More information can be found on Open Design Alliance (ODA) site and on Wikipedia article on DWG file format