Global Mapper v25.0

Use SDK for data import/export but ignore projections

MattC Global Mapper User
edited September 2012 in SDK

We would like to use the SDK to import data from a variety of file formats and export the data in formats that our program recognizes. However, we will not have projection information for any of this data and nor do we want it. We simply want to convert the data between file formats.

Would anybody be able to suggest what the best/easiest way to do this might be please?

As far as I can see, we might be able to achieve this by setting the SDK to a known ‘default’ projection and then use the QueryProjectionCallback function to specify that the data being loaded is also in this default projection. We would also use the ‘default’ when exporting. This assumes that there will be no re-projection of the data at any stage, as long as the SDK believes it is all in the same projection.




  • global_mapper
    global_mapper Administrator
    edited September 2012

    So long as you are only loading a single file at a time for conversion and don't care about its placement on the earth, using the default projection will work just fine. No need for the QueryProjectionCallback in this case, just pass in the load flag to use the default projection.

    Then when exporting just use the GM_GetPixelElevation or GM_GetPixelColor functions (or their full-row equivalents) to get the raw color/elevation data through the image and export it. For vector exports access the individual area, line, and point features and export those.

    Let me know if I can be of further assistance.


    Global Mapper Guru