Elevation Display Related Bug v15.0 b100913)

kbelliskbellis Global Mapper UserPosts: 404Trusted User
edited October 2013 in Bug Report
Elevation Display Related Bug v15.0 b100913)

I know others have reported this bug in the past, but I haven't seen it mentioned for v15.



  1. Begin new Global Mapper session.
  2. Configuration, General tab, Elevation Legend Display/Export Units, Statute (ft).
  3. Configuration, Vertical Options tab, Elevation Display Units, Statute (ft).
  4. Configuration, Projection tab, SPCS, Planar Units FEET (U.S. SURVEY).
  5. Load LiDAR data files (Ground only)
  6. Running cursor over points, Global Mapper reports in lower left corner elevation at cursor in units of meters.
  7. Configuration, Projection, SPCS, Planar Units FEET.
  8. Running cursor over points, Global Mapper continues to report elevation at cursor in units of meters.
  9. Overlay Control Center, select all LiDAR layers, Options, Vector Options, Elevation Units, FEET.
  10. Running cursor over points, Global Mapper misreports elevation at cursor in units of feet but in reality the numeric value is unchanged. Additionally, the Elevation Legend misrepresents hypsometric color values.
  11. Feature Information Tool similarly incorrectly displays elevation in selected display units.

elevation display bug 01.PNG



I'm unable to locate any other places within Global Mapper where the user is able to fix this problem of Global Mapper misreporting elevations.

Suggestion: During loading of LiDAR data, Lidar Load Options window include check box to convert vertical units rather than forcing user to export in desired units, unload and then re-import.

Comments

  • tjhbtjhb Global Mapper User Posts: 454Trusted User
    edited October 2013
    I don't think these are bugs.

    As I understand it (maybe incompletely), the elevation unit options generally apply to "elevation" layers, which in GM means one type of raster layer (the other being images).

    The exception is in your point 9: the setting for elevation units for vector data, available under layer options. But that, like the projection layer "option", is for telling GM how to interpret your data correctly. Setting it to FEET means: the elevation attributes express height in feet. If the source data actually expresses height in metres, then feet would be incorrect.

    The feature information tool displays attributes of the data, the raw numbers, with no conversion applied. (No measurement either. It's not like a line, having a dimension that can be measured, using a variety of units. There is no actual line in the Z axis, just a number.)

    On-the-fly unit conversion might be useful for point and vector data, but it might be a hidden source of confusion too.
  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited October 2013
    Thanks for the explanation Tim that is correct. Note I am on vacation in Mexico so the response on these is slower than normal. I am flying back tomorrow so I should be all caught up by Monday.

    Thanks,

    Mike
    Global Mapper Guru
    geohelp@bluemarblegeo.com
    Global Mapper
  • kbelliskbellis Global Mapper User Posts: 404Trusted User
    edited October 2013
    tjhb wrote: »
    The feature information tool displays attributes of the data, the raw numbers, with no conversion applied.

    That's not what I'm seeing:
    meters-shouldn't-be-displayed-02.png
    tjhb wrote: »
    On-the-fly unit conversion might be useful for point and vector data, but it might be a hidden source of confusion too.

    I'm not sure I understand what that might look like, but presently the confusion that people are seeing is in the open:
    meters-shouldn't-be-displayed-01.png
  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited October 2013
    Kelly,

    Ah yes I see what you mean. That display was always in the native elevation units of the layer, but I've updated it now to use the current display/export elevation units. I have placed a new build at http://www.bluemarblegeo.com/downloads/global-mapper/global_mapper15.zip with the latest changes for you to try. Simply download that file and extract the contents into your existing v15.xx installation folder to give it a try. If you are using the 64-bit v15 version there is a new build at http://www.bluemarblegeo.com/downloads/global-mapper/global_mapper15_64bit.zip .

    Thanks,

    Mike
    Global Mapper Guru
    geohelp@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation
  • kbelliskbellis Global Mapper User Posts: 404Trusted User
    edited October 2013
    Thanks Mike.

    Another idea for the compost heap:
    I know I'll never be able to afford GeoCalc, but an idea tangent to this and applicable to GeoCalc functionalities would be adding a little vertical datum box on the status bar next to the point elevation; e.g., [3.478 ft] MLLW, NAVD88 Geoid12A, etc.
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