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Folks,

We have an AutoCAD file that has been treated very badly. Originally it was LatLong projected GIS data but a contractor with no idea about spatial data exported the data as simple CAD coordinates and scaled the CAD by 200K to get into some sort of reasonable scale.

We're trying to work out how to transform the CAD back into LatLong.

We tried defining a custom projection with a scale of 0.000005 but we're getting errors saying FME can't start the projection engine.

In simple terms

1. the drawing is in a known spatially damaged state

2. If we could scale the drawing by 0.000005 the drawing would be in a plane expression of LatLong

3. We then need to somehow tell FME how to deal with this

Sorry for the odd post but we're having a lot of trouble with this.

Thanks in advance.

Looking at your steps, I would suggest to use a Scaler-transformer to scale the drawing into the right coords (remember to set both X and Y to the same scale) and secondly I would use a CoordinateSystemSetter using 'LL84' or 'EPSG:4326' to bring the coordinates back to the original coordinate system.


Looking at your steps, I would suggest to use a Scaler-transformer to scale the drawing into the right coords (remember to set both X and Y to the same scale) and secondly I would use a CoordinateSystemSetter using 'LL84' or 'EPSG:4326' to bring the coordinates back to the original coordinate system.

Thanks @lars_de_vries. That is what we did. Our mistake was treating the drawing as degrees. Once we scaled the drawing and set the projection to non-Earth meters we were able to achieve a transformer flow that produced the right result.

 


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