[GRASSLIST:8615] New d.rast.arrow capabilities

[David Finlayson]

I filed a bug about d.rast.arrow not saving a command to the monitor
history which prevented the drawing of arrows after zooming or when
using d.out.png with arrows. Hamish Bowman took a look at it and gave
d.rast.arrow a complete make-over. Now instead of just pointing in 8
directions (d.rast.arrow was originally written to visualize flow
directions from D8 algorithms), the arrows are fully 360 degrees and
scaled by magnitude. We've now got a good start towards a general
vector plotting tool in grass. Talk about support!

Here's an example from my research (beach geomorphology) how you might
use it (1 Mb):

http://students.washington.edu/dfinlays/beaches/images/wave_energy.png

Its a plot of beach elevation change and the arrows are wave energy fluxes.

You can get this from CVS.

Thanks Hamish!


--
David Finlayson
Marine Geology & Geophysics
School of Oceanography
Box 357940
University of Washington
Seattle, WA  98195-7940
USA

Office: Marine Sciences Building, Room 112
Phone: (206) 616-9407
Web: http://students.washington.edu/dfinlays