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Create surface from DEM or DTM

PostPosted: Tue Apr 27, 2021 12:47 pm
by peamouth
I haven't found a way to create a *.tin from a downloaded DEM or DTM. The State DNR has such data available from LIDAR surveys and I would like to create a surface. Is it possible?

Re: Create surface from DEM or DTM

PostPosted: Wed Apr 28, 2021 7:23 pm
by gskelhorn
Hmmm... I have the Civil Suite license so I am not sure if the Grid File Utilities command is available in Survey. See the manual http://files.carlsonsw.com/mirror/manuals/Carlson_2021/source/Site_Road_Design/Surface/Grid_File_Utilities/Grid_File_Utilities.html

Try to run command GFU

If it is available you can import a DEM to a Carlson Grid.

My understanding is the Carlson Point Cloud program is designed to work with larger data sets like LiDAR. See https://classic.carlsonsw.com/archives/working-with-cloud-data-and-surfaces/ and https://www.carlsonsw.com/product/carlson-point-clouds

Another option would be to use the GDAL programs to extract an XYZ file and use that as the source data for Carlson triangulation (TRI) command. See https://gdal.org/programs/gdal2xyz.html

Re: Create surface from DEM or DTM

PostPosted: Thu Apr 29, 2021 3:38 pm
by peamouth
It's not actually a DEM, but a DSM file or DTM file I want to import. The DEM option is available. Thanks for the help. I don't have the point cloud module, but it looks like it would work. In the meantime, I know smart people who help me create the *.tin, so until I figure this out, that's what I'll do. :D

If you would like to give it a try, follow this link: https://lidarportal.dnr.wa.gov/#47.51508:-120.45677:16