[GRASS-user] Re: Earthquake PHP map - was: Re: Geocentric Datum of Australia 1994

[Hamish]

Hamish:
> >  http://grass.itc.it/spearfish/php_grass_earthquakes.php
> >  low priority wishes:
> >  - how to brighten the Blue Marble colormap (RGB raster)?
> > i.landsat.rgb?
> 
> It is running in GRASS 6.1 (yes!), so no i.landsat.rgb... I
> could rip out the relevant parts from the script and try.

ok, or from a newer version of GRASS generate a color map then
drop it over the Blue Marble map's colr/ file.

I've just tried i.landsat.rgb with the Blue Marble 2002 (no bathy),
it makes the Sahara-Gobi quite contrasty.

So i.landsat.rgb is good at adjusting pseudo-contrast. A method to
adjust pseudo-brightness is:

g.region res=1
r.mapcalc "one = 1"
g.region res=0:10
r.composite r=BlueMarble2002.red g=BlueMarble2002.green \
   b=BlueMarble2002.blue out=BlueMarble2002_10min.rgb
d.shadedmap drape=BlueMarble2002_10min.rgb relief=one bright=25


Sahara-Gobi still glow too brightly, some experimentation might be
needed to find a compromise?
(tip: set resolution very coarse during trial and error for speed)


also a gee-whiz wish would be to use the Blue Marble NextGen image of
the current month instead of hardcoded May. :)

 
> > Richter scale is logarithmic, but bubble radius is linear classed
> > to int order of magnitude- the whoppers get hidden in the noise.
> 
> Uhm, good point. Solutions welcome (ideally a d.vect.thematic patch,
> maybe a flag?)

I had hoped to add a new size_column= option to d.vect when I found some
time or the need became pressing, maybe it would help too.
  https://trac.osgeo.org/grass/ticket/600



Hamish