DerrickW

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DerrickW
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  • Export multiple checked Layers or Groups to separate files

    As Bob said, this is possible when exporting to a shapefile.  Since I use KML files a lot for UAS flight planning, I will often export all of my polygons to shapefile split exports based on the FlightNumber attribute, then use the batch conversion tool to convert to KML.   Not the ideal approach, but it works for my use case. 
    sphillips
  • Title blocks and Map borders in Global Mapper

    The map layout editor needs other tools to support this, like the ability to create polylines / symbols.  Text callouts with annotations/arrow leaders and the option to have more than one map view element in a single page are also huge limiting factors of making exhibits with global mapper. 

    *All* of us (at my company) enjoy using global mapper much more than the alternatives, but most of us begrudgingly opt for the alternative on stuff that we have to generate exhibits for. 

    This is the general layout that we use on some projects, but all of the project managers are always pushing for uniformity in exhibits & titleblocks and GM is the only software we use that this is difficult on.  I've used pre-rendered blank pages with the title block on it as an image and inserted it in the background, but it's difficult to work with and frustrating to update as our company title block updates. 
    chaiRGBrown
  • Gridding and Contouring options

    Best "suggestion" post I've read on these forums.  Love it. 
    TRB426
  • Using Check shot GCPs

    dpitman said:
    Hi Folks,

    I don't yet have GM.

    In GM, how do you examine the coordinates of check shots to compare them to surveyed values?

    Thank you,
    Dave
    Like a point to point inverse?  Not sure how to do that in global mapper, as I normally do that in CAD.  

    Since you're using the term "GCPs", I'm assuming that you're a drone user. ;)  The way I compare checkshots to my drone-derived DSM/DTM is: 
    1: Import GCPs
    2. Use calculate/copy attributes tool to copy "ELEVATION" attribute to a new attribute called "Observed"
    3. Turn on DSM/DTM layer if it's not already on
    4. Select all checkpoints and right-click--->analysis---> apply elevations to features
    5. Use calculate/copy attributes tool to copy "ELEVATION" attribute to a new attribute called "Predicted"
    6. Use calculate/copy attributes tool with the formula OBSERVED - PREDICTED, and write it to an attribute called "Delta"
    7. change display labels to "Delta" attribute.  Export as CSV to calc RMSE, if needed. 

    You can also convert the DSM/DTM to a point cloud (or "Create points at elevation grid cell centers") and use the lidar QA/QC tool.   The lidar tool will sample nearby points.  The workflow above will sample a single cell/pixel at the same XY coordinates as your control point. 
    TRB426
  • Creating a surface with the same shape as the terrain

    Above advice is good, but I take it a step further by converting the elevation grid to points and then creating a bounding box that's point-to-point from that.  Prevents the weird triangles from being created along the edge of the cropping polygon. 
    kfroese