On Tue, Nov 19, 2019 at 11:03 PM Rahkonen Jukka (MML) <jukka.rahko...@maanmittauslaitos.fi> wrote: > > Hi, > > I would like to get some hints about using gdal_grid or some other utility > for lake bathymetry. What I have is typically rather sparse point data of > depths and the shoreline that includes the islands as in the attached image. > The shoreline and all the area that is not lake basin should have the > altitude of zero in the resulting DEM. It means that interpolation should not > overshoot across the shoreline over the dry land. > > Gdal_grid seems to miss an option for handling the shoreline so I made a test > by converting the vertices of the polygon rings into depth points. I also > filled area around the lake with a gridded points of zero altitude but the > method feels stupid and tedious and the result was not so fine when it comes > to keep the shoreline and land area near it totally flat. > > If there are any specialists on bathymetry reading I am eager to learn how to > handle my data.
Just FYI, GRASS GIS offers several methods as well: - https://grasswiki.osgeo.org/wiki/Interpolation#Reinterpolation_of_.22sparse.22_.28scattered_points_or_lines.29_maps - https://grasswiki.osgeo.org/wiki/Contour_lines_to_DEM Markus _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/gdal-dev
