[Xastir] Area Color fills and highway colors

[Tom Russo]

On Sun, Jan 16, 2005 at 11:19:14PM -0600, we recorded a bogon-computron collision of the <tim at gimmel.org> flavor, containing:
> All,
> Maybe I don't understand the feature.  I downloaded county maps from
> http://xastir.tamu.edu and I believe they are shapefiles made from
> tigerdata.  

Yes, but they're only the line features.  

> My question is: if I set "fill" to "yes" in the properties
> dialog, and I enable the global map fills, shouldn't just the counties
> that I have marked be filled with color?  

No.

The shapefiles on xastir.tamu.edu have been created with ogr2ogr run over
the TIGER/Line files to convert them to shapefiles, which only captures the 
linear features, not the area features.  It took a little while for us to 
figure out how to to the polygon features, and nobody has done the conversions 
the way that Derrick Brashear did them for the linear features.

If you want area features from TIGER data, you have to install GDAL,
download the raw TIGER files, and do the conversion yourself.  Instructions
for how to do this are in README.MAPS (search for "Xastir_tigerpoly" for
the command line necessary, and search for "www.census.gov" for the link
to the raw 2003 TIGER/Line data).  So far nobody has stepped up to the plate 
and offered to run all the states through this process and put them up on a 
web site.  

> The way it is working now is
> when the "Enable Area Color Fills" is checked, the whole map turns pink,
> regardless of how the properties are set.  Not what I expected.

That's odd.  I've seen this behavior when attempting to use fill on maps
that don't have dbfawk files defined properly for them, but it shouldn't
apply to the tiger shapefiles from A&M.  The default fill color for area 
shapefiles without dbfawk definitions is magenta --- enabling fill on such a 
shapefile could make your entire map pink.  Bleah.  But since the 
xastir.tamu.edu shapefiles have no areas to fill, that shouldn't happen.

Are you viewing only TIGER data from xastir.tamu.edu, or do you have other
maps being displayed as well?  Try using the map chooser to turn them 
off one by one and see if the pink color goes away --- the map that does this
needs a dbfawk file to go with it to prevent filling that way.  If the TIGER 
shapefile is the only file you're attempting to view and this filling happens, 
then there's something else wrong.

I just tried enabling fill in the map properties for one of the TIGER line
features files (which is not something you have to do if you're using 
dbfawk-enabled xastir --- the filling of shapes is defined in the dbfawk file 
then).  I did not see any bizarre filling of the map.  We might need to get
more specifics from you to understand what's going on.

> Also, just one other question.  Is there any easy way to change the
> color of the streets and highways?  Currently in these maps streets and
> highways are black.  It would be nice if I could make them white, and I
> could use a black background.

Yes, it's easy if you're using the "dbfawk" version of xastir (i.e. you have 
pcre installed and didn't specify "--without-dbfawk").  Edit the file 
/usr/local/share/xastir/config/tgr2shp.dbfawk.  You will need to look for the 
line where the dbfawk file sets the color of the particular features you're 
interested in, and add a "color=15" (or change the current "color=8" to 
"color=15" if the line already sets a color).  Color 15 is white.
This file will get clobbered, though, if you update xastir from CVS and 
do another make install, so you'll also have to change it in your source's
"config" directory.

If you're not using dbfawk, you'll have to modify the map_shp.c file.  I
recommend not going that route.

-- 
Tom Russo    KM5VY     SAR502  DM64ux         http://www.swcp.com/~russo/
Tijeras, NM  QRPL#1592 K2#398  SOC#236 AHTB#1 
 "When life gives you lemons, find someone with a paper cut."