Global Mapper v25.0

OS Terrain 5 and how to create a Grid layer

SteveMac
SteveMac Global Mapper User
edited March 2014 in Elevation Data
I have successfully been using UK Ordnance Survey's Land Form Profile 5 data to create slope maps, but they do not supply data in that product now, only OS Terrain 5. That can be supplied in 3 formats - Contours GML, Contours ESRI Shape files or Grid, and samples are available to down load at https://www.ordnancesurvey.co.uk/business-and-government/licensing/sample-data/discover-data.html.

I have downloaded a sample tile of all three types and can successfully load them using the "Open Data File..." command, but I cannot produce a Grid layer, ie right-cliking on the data, choosing Grid, etc to produce a slope map.
Firstly, what data format should I use?
Secondly, by what process should I import it?
Thirdly, how do I create the Slope map?

Any help would be very much appreciated. Thank you!

Steve

Comments

  • SteveMac
    SteveMac Global Mapper User
    edited March 2014
    ref above, I should say I am using GM v 14
  • stihl
    stihl Global Mapper User Trusted User
    edited March 2014
    Have you tried the 'Create elevation grid from 3D vector data' under Analysis on the menu bar? There you can specify the sample spacing, interpolation etc etc
  • global_mapper
    global_mapper Administrator
    edited March 2014
    Download the grid data. It loads right in from the .zip as a terrain grid for me. Then you can select the slope shader to get a slope map.

    Thanks,

    Mike
    Global Mapper Guru
    geohelp@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation
  • SteveMac
    SteveMac Global Mapper User
    edited March 2014
    Thank you Mike! That works perfectly using the Grid data. I think I was trying to be too clever, and extracting the zip file first, then loading only one file!

    Supplementary question. The ESRI shape file format that can be downloaded contains contour data, as opposed to Grid data. is it possible to create slope maps from this using the "Create Elevation Grid" feature on this? The data seems to have height data associated with it. I get the message "failed to generate any elevation grid tiles", so I am obviously doing something wrong.
  • global_mapper
    global_mapper Administrator
    edited March 2014
    Yes if the contours have an elevation attribute you can first go to the Options dialog for the contour layer and specify which attribute contains the elevation, then you can generate an elevation grid directly from the contours.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Guru
    geohelp@bluemarblegeo.com
    Global Mapper
  • SteveMac
    SteveMac Global Mapper User
    edited March 2014
    That works perfectly!
    Thank you
    Steve