DEM for inland lake

wmiswmwmiswm Global Mapper UserPosts: 220Trusted User
edited June 2012 in Elevation Data
For generating DEM, can I use polygon to specify elevation? If not, how to deal with the elevation of inland lakes, airports, football fields etc where the polygon is essentially flat at a certain elevation?

Comments

  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited June 2012
    Yes, simply add an ELEVATION attribute to the area to flatten with a value like '30 m' (or whatever the elevation is), then select that with the Digitizer Tool, then right click and select the Advanced Feature Creation option to Create/Flatten Terrain. This will create a new terrain layer that has the elevation values from that layer.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Guru
    gmsupport@bluemarblegeo.com
    http://www.globalmapper.com
  • wmiswmwmiswm Global Mapper User Posts: 220Trusted User
    edited June 2012
    I have one more question. For a river, the elevation is continuously changing along its length, but should be level to the same elevation across its width. What should be done in generating DEM in such situation?
  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited June 2012
    What you can do is perhaps put the river on it's own layer, use the Digitizer Tool to resample it to have a lot of vertices, then right-click on that layer in the Control Center and select to create an elevation grid from that and use the grid tightness slider to only create the grid near the vertices. Then you should just get terrain near the river and the height will vary along the river.

    Thanks,

    Mike
    Global Mapper Guru
    gmsupport@bluemarblegeo.com
    http://www.globalmapper.com
Sign In or Register to comment.