Global Mapper v25.0

V20 vs V19 - ASC interpolation seems to have changed

veddycent Global Mapper User

1 ASC file exported as DXF mesh from GM v19 and v20 produce different results. In some areas the difference is +4m!
This is a real pain as terrain tiles do not match between versions so the question is which is the correct one?

As far as I can tell all settings are the same (configuration, importing asc and exporting dxf).
Has any of the interpolation maths changed?



  • bmg_bob
    bmg_bob Global Mapper Programmer
    Hello Ved,

    I suggest that you contact Blue Marble Support directly via email ( to see if there has been a change to the interpolation math. Please include a detailed description of your workflow, including screen captures of your export options, and the ASC file you are using as a source for the export. This will allow the support team to reproduce the problem locally and determine the next step. Thank you.