[GRASSLIST:2] Re: [GRASS5] New GIS Manager adds transparency to layers

[Thomas Adams]

Michael,

THAT is very cool! Can't wait to take it for a spin around the block…

Tom


Michael Barton wrote:
> IR17;ve just finished phase 2 of the GIS Manager update and it’s 
> pretty exciting. At first glance, it looks a lot like the one I’ve 
> 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 I’m 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 ‘under the hood’ 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 doesn’t 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 OS’s 
> 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 
> <http://www.public.asu.edu/%7Ecmbarton/files/grass_screenshots/gism2-2.jpg>
> _
> I’ve committed all changes to the CVS. For those of you with binary 
> versions of GRASS who would like to try it, I’ve 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/ 
> <http://www.public.asu.edu/%7Ecmbarton/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/ 
> <http://www.public.asu.edu/%7Ecmbarton/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 
> <http://www.public.asu.edu/%7Ecmbarton>


-- 
Thomas E Adams
National Weather Service
Ohio River Forecast Center
1901 South State Route 134
Wilmington, OH 45177

EMAIL:	thomas.adams at noaa.gov

VOICE:	937-383-0528
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