Global Mapper v25.0

TIN Simplification

kgrover
kgrover Global Mapper UserTrusted User
edited January 2014 in Elevation Data
Is there a way to simplify a TIN surface intelligently?? Such as removing triangle if there isn't a vertical change greater than a chosen tolerance such as 10 cm??

We tend to use TIN surfaces quite often as opposed to raster surfaces, just to preserve more detail of drainage courses, roads, etc., so we are looking for a way to intelligently simplify in GM.

Kevin

Comments

  • kgrover
    kgrover Global Mapper User Trusted User
    edited January 2014
    To add to my original post, are there good ways to export a TIN out of GM?? I don't really want to go to an DXF format, or to any gridded format. Ideally I would to export to a LandXML file, but I don't believe that is possible.

    Any assistance would be appreciated.

    Thanks.
  • global_mapper
    global_mapper Administrator
    edited January 2014
    You could select the triangles with the Digitizer Tool then right-click and select the Analyze/Measure submenu command to calculate elevation statistics which will add attributes like the min, max and average elevation. You could then right-click on the layer in the Control Center and select the CALC ATTR option and subtract the MIN_ELEV from MAX_ELEV to get the difference, then search on those and remove the smaller ones. Of course you probably want to somehow combine those triangles to simplify the TIN rather than just deleting them and that isn't yet possible in an automated fashion.

    There is not yet support for exporting to LandXML, but that is on our todo list. There are some other TIN export formats besides DXF, like Vulcan .00t files, STL, or even 3D Shapefiles.

    Thanks,

    Mike
    Global Mapper Guru
    geohelp@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation