I taught an ArcGIS class last semester and my
impressions are very similar.
ArcGIS looks sleak on the surface, but it is
incredibly sluggish, unstable and missing a
lot of basic functionality.
Since version 8.0, ESRI has added all sorts
of toys (ArcGlobe, ArcScene, ...), but
the really important stuff, such as the
Spatial Analyst has not seen a major update
since ArcView 3.x.
During my classes, 2-3 machines were regulary
unavailable, because ArcGIS kept crashing or
just wouldn't do what it was told to.
Did you know that the 3D "Analyst" is pretty
useless if you are working in custom projection?
Nice, isn't it.
Over and over again, we ran into unexpected
problems and well-hidden functionality.
Have you ever tried to get excavation data in
a simple X-Y system into ArcGIS? It's a nightmare.
GRASS has a much cleaner interface, is more reliable
and manages more data with less resources.
And on top of that: my students told me after a
small introduction to GRASS GIS that they
thought it was a really "cool" and professional
system.
What can I say?
----- Originalnachricht -----
Von: Michael Barton <michael.barton@asu.edu>
Datum: Samstag, 11. März 2006 6:24 pm
Betreff: [GRASS5] Re: [GRASSLIST:3] Re: New GIS Manager adds
transparency to layers
I¹m co-teaching an interdisciplinary Remote Sensing and Quaternary
Landscapes class with a couple of colleagues in other schools. We
decided to
show students how to do some basic GIS-related tasks like import a
DEM,reproject it from latlon to UTM, do a shaded relief map, drape
it with
color, create basic slope and aspect maps, and do profile
analysis‹and do it
on 2 systems ArcGIS 9 and GRASS 6.1.My colleague (who is eager to learn more about GRASS) did this in
ArcGISthis week and I will do the same in GRASS after Spring Break.
Having barely
touched Arc in a couple years now, I was feeling bad about showing
studentsthe complications in getting GRASS started and some of the
esoteric aspects
of this complex program. Then I watched the ArcGIS presentation.
Easy to
start and then the difficulties started. Sure you can open any map
in an
projection, but... Getting the projection right so that the maps
actuallyoverlay correctly is more difficult than in GRASS. Hill
shading/shadedrelief is about the same in both. Draping is
definitely more versatile in
GRASS‹especially with the new transparency. Slope and aspect are
marginallyeasier to do in GRASS and much easier to find in the
menus. Profiling is a
LOT easier in GRASS, even though it is still tied to the x11 displays.
Several times my colleague mentioned, if only we could... And I
said, you
can do that in GRASS. For example, after finally getting profiling
to work
in ArcGIS (He needed to restart...so I don¹t feel quite so
embarrassed about
occasional lockups in the GIS Manager, though a want it to be bug
free), he
said, if only we could output the profile points in some way. GRASS
has a
couple ways to do this‹via d.profile and r.profile.Since I¹ll be following the ArcGIS demo, I¹ll be able to feel
pretty good
about the GRASS demo when I do it.Michael
On 3/10/06 5:01 PM, "Ian MacMillan" <Ian.MacMillan@pomona.edu> wrote:
> Michael, I haven't tried this out yet, but it sounds excellent.
Cheers to all
> of your efforts to make GRASS more user-friendly for newbies. I
am going to
> feel less guilty about making my students use GRASS in their
classes instead
> of Arc.
>
> -Ian
>
> On Mar 10, 2006, at 12:59 PM, Michael Barton wrote:
>
>> I¹ve just finished phase 2 of the GIS Manager update and it¹s
pretty>> exciting. At first glance, it looks a lot like the one
I¹ve been working on
>> and have in the CVS now, but with a couple of important
exceptions. One is
>> that transparency is now supported for all GRASS layers.
>>
>> The second will probably generate the most discussion, so I¹m
ready to duck
>> and run for cover. Now GRASS is consistent with other GIS
programs and more
>> intuitive (as much as I am skeptical about that term) in that
the uppermost
>> layer in the layer tree is also the top map in the display.
Related to this,
>> new layers insert directly above the currently selected layer
instead of at
>> the bottom of the layer tree.
>>
>> The main changes come Œunder the hood¹ of this version of the
GIS Manager.
>> It uses g.pnmcomp to composite a set of maps (each rendered as
*.PPM files)
>> into a visual display. One of the results is that now GRASS is
significantly>> faster in adding new layers, turning layers on and
off, and changing layer
>> attributes‹only the new or changed layer needs to be rendered;
the others
>> will just be re-composited into a display from existing PPM
files. This all
>> happens in a GRASS .tmp directory, so that it doesn¹t clutter up
your home
>> directories. The other important thing about this new
architecture is that it
>> makes GRASS even less dependent on the xdriver and PNGdriver for
>> visualization. GRASS can become more easily portable to
different OS¹s and
>> GUI frameworks. It is also more scriptable. You can write a
script that will
>> create a complete, multilayered map, and output it to a graphics
file.>>
>> One consequencer of this new architecture is that the GIS
Manager does not
>> currently support display output to PNG files. With GDAL
(required for many
>> GRASS features) and ghostscript installed, it does support
output to PPM/PNM,
>> TIF, JPG, BMP, EPS, and PDF.
>>
>> Command line usage is still supported in several ways‹the old
xterminal is
>> still there, there is the new command console, and you can add
command layers
>> to the layer tree and display them.
>>
>> You can see a screen shot of semi-transparent soil vector areas
overlaying a
>> raster shaded relief map at
>>
>>
http://www.public.asu.edu/~cmbarton/files/grass_screenshots/gism2-2.jpg
>>
>> I¹ve committed all changes to the CVS. For those of you with
binary versions
>> of GRASS who would like to try it, I¹ve posted packages you can
use to
>> replace your current GIS Manager on my website. For full
functionality, you
>> need a version of grass that is dated 21-February-2006 or later.
For those of
>> you with a slightly earlier version, I made a second package
with all
>> functionality minus transparency. Here are the links.
>>
>> New GIS Manager files
>>
>>
>>
<http://www.public.asu.edu/~cmbarton/files/grass_gismgr/gism_rc4_20060307.tgz>>
>>
>> New GIS Manager files for people with recent, but pre-21
February 2006
>> binaries.
>>
>>
<http://www.public.asu.edu/~cmbarton/files/grass_gismgr/gism_rc4_20060307pre_>>
02-21.tgz>
>>
>> Enjoy
>> Michael
>>
>> ______________________________
>> Michael Barton, Professor of Anthropology
>> School of Human Evolution and Social Change
>> Arizona State University
>> Tempe, AZ 85287-2402
>> USA
>>
>> voice: 480-965-6262; fax: 480-965-7671
>> www: http://www.public.asu.edu/~cmbarton
>>
>> >
>> >
> What happens if a big asteroid hits Earth? Judging from realistic
simulations> involving a sledge hammer and a common laboratory
frog, we can assume it will
> be pretty bad.
> - Dave Barry
>___________________________
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Arizona State University
Tempe, AZ 85287WWW - http://www.public.asu.edu/~cmbarton
Phone: 480-965-6262
Fax: 480-965-7671