[Xastir] Downloading Tiger Maps

[Tom Russo]

On Sat, Dec 05, 2009 at 10:57:06AM -0600, we recorded a bogon-computron collision of the <jhunter at sardognetwork.org> flavor, containing:
> 
> 
> I have been playing around with downloading the Tigermaps and saving 
> them locally on my system. I have figured out some of the files I need 
> but the biggest issue I am having is that the maps I save locally do not 
> have the same quality and clarity as the ones that are accessed from the 
> net.
> 
> I am assuming that the data/shapefiles I am downloading are the same 
> that are pulled from the net on the fly.

If you're downloading shapefiles, then no, you're not getting exactly the
same thing as "Online/tigermap.geo."

The "tigermap.geo" file causes Xastir to download a rendered image from 
a US Census server.  That server takes the TIGER/Line data and creates a 
usable (if distorted) map image out of it.  (The distortion is due to their
using a sinusoidal projection, and is very visible at high zoom levels in 
Xastir).

The shapefiles you get from the Census web site have the same information,
but are rendered by Xastir itself (without distortion).  They will not look 
the same.  Some effort has been expended by various volunteers to try to make 
Xastir render them in a manner that is close to the way that the tiger server 
does it, but for a number of reasons they cannot be made exactly the same.  
There has been some success in making the colors the same and so forth, but
labeling, layering, and symbology cannot be an exact match.

-- 
Tom Russo    KM5VY   SAR502   DM64ux          http://www.swcp.com/~russo/
Tijeras, NM  QRPL#1592 K2#398  SOC#236        http://kevan.org/brain.cgi?DDTNM
  In some cultures what I do would be considered normal. 
                                  -- Ineffective daily affirmation