I have got an AudoCAD .dwg file which is based on some location of Sweden, but I don't know what is the internal projection of this file. How can I get projection information from this .dwg file?
Actually when I convert this .dwg file into a shapefile by using FME software, then it requires projection information (source file projection) for converting it into shapefile (the target format), and I don't know what is the projection of this .dwg file. Is there any way to get to know about the projection of source file .dwg ?
Best Answer
There may or may not be projection information in the autocad drawing. If there is it can be read only with one of the GIS products from Autodesk (i.e. map3d, civil3d, mapguide).
You will need to either...
1. use an autodesk product to discover the assigned crs.
2. contact the originator and find out the crs.
3. convert to a format you can use (probably with no transformation), and then begin to discover the crs.
4. project the data with esri arcmap (which will create a world file for the dwg). [I don't normally use this method]
5. As Dano suggest rubbersheet (use a copy)
If you can send along the dwg or make it available for open online (autocad can open online dwg), I can take a look for you.
If there is an item in your dwg that is identifiable on the ground or another map, you can open the dwg with a free viewer (autodesk trueview), identify the coordinates at the known point and then begin to ascertain the correct prj.