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MAPublisher Slightly Skewing Shape

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#1
dMoriarty

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It seems like any time I export a shape file from MAPublisher, it results in a constant, slight misalignment. As pictured in the example images the colors correspond to: 
 
Purple: Unedited, fresh from the web NED imported into Arc.
Yellow: Fresh from the web NED that's been imported into MAPublisher and exported with no modifications made.
Green: The error on a file I did more extensive work on, though the area I clipped this from was not a polygon that had any changes made. The error seems to be constant on the file as a whole regardless of how much editing was done to the polygons.
 
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You can replicate this by simply importing Natural Earth Data 1:10m and simply importing and exporting it from MAPublisher, then comparing it to the original shape file in Arc or what have you. 
 
Two possible ideas people have presented have been to check for Bezier curves and make the art board as large as possible- neither which seem to change the result. 
 
If you have any ideas on how to correct this, let me know! Documentation on MAPublisher troubleshooting is pretty scarce. 

 



#2
Hans van der Maarel

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What's the size (real-world units) of the error we're talking about? Illustrator does use a lower precision for its page coordinates than what a GIS would use, so there is a potential for rounding errors, though I've never seen it become a real problem.

 

The "make the artboard as large as possible" refers to that precision, but it sounds like that's not the solution. Bezier curves is highly unlikely: the NE data is in shapefiles and there's no automatic creation of Bezier curves upon import.

 

What exactly did you do to the data? Accidentally shifting it doesn't seem likely as the shape has changed as well as the position.

 

Does it happen with every file, or just this one?

 

What happens if you check the result in something other than Arc (QGis for example)?


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#3
Avenza

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when importing the Natural Earth data into Illustrator did you recieve an error message such as this when double clicking on the "Creating Illustrator artwork" error log message:

 

"Your map file contains elements that exceeds Illustrator's point per path limitation.  MAPublisher has imported the file however certain objects were simplified."

 

 This is the message we recieved, telling us that the lines were simplified upon import as it exceeds Illustrator's limitation.  This is likely why you are seeing the difference between the two shapefiles.



#4
David Medeiros

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Although I don't see it here, note that exporting lines with bezier curves to .shp file also alters them as the curves are converted to straight line segments in the .shp file.


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