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Web-Based GRASS!

Whoo-hoo! After a number of tweaks, I finally was able to install command-line GRASS GIS onto this site. I've been working off of Aaron Racicot's tutorial for about a week now. Actually being able to understand and fix some of the errors in the ./configure process is feeling pretty rewarding. I had to manually set the pathways for FFTW and TK using --with-fftw-includes and --with-tclktk-includes respectively. Also, ran into an issue with NAD2BIN not being explicitly laid out as well, but I was lucky enough to find a forum post stating that I needed to use the command, 'export NAD2BIN=/home/.../bin/nad2bin'.

I'm not all that familiar with the command line syntax of GRASS, so I actually had to use a local install to view some sample syntax, and modify it for use on the web instance. Pretty fun.

I'm wondering if there is anyway for a user to access the geoprocessing functionality of this GRASS install w/o logging into the server. Furthermore, could it be possible to tie this into a mapserver / openlayers install? It would be amazing to recreate this ESRI on-the-fly geoprocessing example using only open source GIS tools.

Anyways, it's a pretty cool feeling to be able to upload a file to the server, run a geoprocessing task on it, and download the results back to my machine!

GRASS 6.2.3 (spearfish):~/usr/local/bin > r.shaded.relief map=elevation.dem shadedmap=shade_test altitude=30 azimuth=270 zmult=2 scale=1 Calculating shading, please stand by. 100% Color table for [shade_test] set to grey

Shaded relief map created and named [shade_test]. GRASS 6.2.3 (spearfish):~/usr/local/bin > r.out.tiff input=shade_test output=/home/matthewkenny/usr/local/gis_workspace/shade_out compression=none WARNING: The map <shade_test> in mapset is a floating point map. Decimal values will be rounded to integer! GRASS 6.2.3 (spearfish):~/usr/local/bin >

And the output image downloaded back to my computer: