Create a pond from lidar data holes.
This may be a basic question as I am new to global mapper. So I have lidar data with holes it it. These areas of no lidar data represent ponds. Is there a way to create pond polygons for the no data areas? I seem to remember seeing it on a youtube video but can't find it now. Thanks in advance.
Answers
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That's a very good question which had me thinking. I too have lidar data with holes. My back of an envelope solution is to go Options, Alter Elevation Values and clamp the invalid data to a value egregiously outwith the terrain elvation. The invalid areas should now show in a striking colour, assuming your lidar grid is shaded.I then created contours at an appropriate level (e.g. 1m). You can now copy the contours that appear around the "holes" using the Digitiser tool, move them to a new layer and then convert them to polygons. There is doubtless an easier way but I do not know it.



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