Global Mapper Pro

Correct rendering of GML raster elevation files when a "startPoint" is specified

I have been using Global Mapper for rendering GML files as raster elevation data, and this is working for many files, but some files are not rending correctly. 

I believe the issue is related to the <gml:startPoint> tags. If the start point is specified as "0 0", the files render correctly, but if start point is anything other than 0 0, there is a shift or offset in the file. I believe this typically happens when the first values in the tuple list would be null. Instead of listing all of those null values, they leave them out and specify a "startPoint" instead.

I wrote my own GML python tool to convert to BIL/HDR format, and properly accounting for the startPoint fixed the issue. 

I can provide example GML files if needed (in which case, please let me know how to send them).

I am happy to provide additional details and information if needed as well. Thank you!


  • bmg_bob
    bmg_bob Global Mapper Programmer

    I suggest that you report this directly to Blue Marble Support via email ( so they can address the problem. Please include a sample data file, and perhaps screen captures that illustrate the incorrect and correct rendering. Thank you.

  • Ok, thank you Bob. I wasn't sure what would be preferred. I appreciate the suggestion and I will certainly do that.


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