[GRASS-user] Processing LiDAR data in GRASS GIS

[Hamish]

Adrian wrote:
> I have LiDAR data in ASCII txt files with only X, Y and Z
> coordinates, which I want to import and create DEM models 
> from in GRASS. I'm new to this kind of data processing.

--> see  http://grass.osgeo.org/wiki/LIDAR

r.in.xyz + r.surf.nnbathy is my favorite combo for this, but
then, I'm biased. 3.5M points should run in a few seconds.
(r.surf.nnbathy from the wiki AddOns page)

The choice between v.in.ascii and r.in.xyz really depends on if
you want to do full analysis on the point cloud or just make a
fast DEM from an already cleaned x,y,z set.

3.5M points is on the limit of the number of vector points you
can work with in GRASS 6 with full topology and database tables
unless you have a computer with lots of RAM. (thus options to
disable first database creation and second topology)


Hamish