[GRASS-dev] d.vect -z zcolor= for LIDAR data

[Hamish]

Hi,

I was looking to change the default zcolor= option for 'd.vect -z', as
"terrain" is not appropriate for local maps where the elevation does not
change by hundreds/thousands of meters. "elevation" seems an obvious
choice (or "rainbow" which is the default for rasters) as it is based on
0-100% instead of hardcoded elevations, but that does not work with LIDAR
points data which is built without topology, perhaps because there is no
access to min/max, or those values are filled with garbage(?). Anyway,
after a long while rendering I get a white image in the xmon.

for LIDAR data there are millions of points and attribute tables
containing GRASSRGB column are pretty much out of the question. just
xyz data, often without topology built.

for example, 0-1000m data is all green:
  v.random -z out=rand2k n=2000 zmin=0 zmax=1000
  d.vect -z rand2k

as is the LAS example on the wiki:
  http://grass.osgeo.org/wiki/LIDAR#Example


also, it would be really nice if basic v.info and v.univar modules worked
on vector maps lacking topology.


any ideas?

Hamish