How do I georeference an AutoCAD file with no real world spatial information?
Hi all,
I am trying to import AutoCAD .dwg files into Smallworld 5. However, the .dwg files have no specified coordinate systems or coordinates. The solution used before was to convert .dwg to .shp and geoference in ESRI ArcMap based on superficial info such as the street name in the .dwg. But we are trying to simplify and speed up the workflow by converting from .dwg to Smallworld 5.1.3 directly using FME. Does anyone have any idea at all if this is possible?
You need some kind of external information to solve this problem. FME will never 'magically' know where to place all these autocad features.
Another way to approach this is by using the Offsetter transformer. At a customer we have implemented it like this:
1) Each .dwg could be linked to a certain area
2) For each area, we created a point in space
3) With the Offsetter transformer, we moved all the elements so that the center point of the drawing corresponds with the predefined point in space.
To summarize, you will need extra data.
I am aware the above might not be a perfect solution, but it might help...
Manual
You can use autocad itself for georeference using the spatial adjustments toolbar or type adetransform in commandline.
Or if you know what the original coordsystem is, you could just set these in the autocad drawings using mapassign .
Automated..
Using fme this should also be possible by creating a blank dwg with correct units and coordinate system.
Read the dwg's you need to convert and then write them to dwg again using the previously created dwg as a template.
Then you can read them to convert to small world.
(this issue or similarly has been addressed in the forum previously)
WIth regards to the first two solutions - we're looking a solution that doesn't require AutoCAD or any other additional software apart from FME. This is because we don't generate the drawings ourselves; they are sent in for us to process into Smallworld. We could possibly request for the drawings to be georeferenced in autocad by the sender but we are trying to make the process simpler for them.
The coordinates in the autocad aren't geographic coordinates - they are coordinates where 0,0 is the bottom left of the drawing. So what we're looking for is a way to geolocate in FME itself.
