[NLRS] Grid map graphics again?

[Dr. Gerald N. Johnson]

Grids and maps are handiest when the drawing system works in degrees and 
fractions. Or degrees minutes seconds. The software I created for 
Frese-Notis weather over the past 20 or more years works that way and is 
driven by a command file. Maps it draws are at www.weather.net. Drawing 
boundaries of grids in its command structure is a line that says "draw 
line 44,-60 to 44,-120" for horizontal lines, and "draw line 20,-90 to 
56,-90 for a north south line. In my software I don't allow Mercator map 
projections, only polyconic and Lambert and a couple more esoteric 
projections for world wide maps. I've collected data for state and 
county boundaries, one source was a US DOT CD. Also collected data for 
elevations which is the radar map background at weather.net from a USGS 
source for a few bucks on a dozen CD-ROM. Its a lot easier to get grid 
boundaries on a projected map with the program that projected the map. 
My program also does text, in English, or other languages using roman 
letters, but also does Kanji, JIS, and shift JIS for Japanese and those 
fonts also do roman and Cyrillic. It will fill a block with color too 
with curved boundaries of a projection or straight boundaries of screen 
space locations. But its not a program publicly available.

I've drawn maps with Autocad sometimes to collect the boundary data when 
I needed a closed boundary and the available data wasn't made of 
sequentially connected lines. Had I a generic public domain drawing 
program where I could have extracted the line data from a .DXF file it 
would have worked as well, I didn't work Autocad hard. Those maps also 
were never display projected.

The crude alternative, is to use grid maps that have been down loadable 
from ARRL and crumcraft, print them, mark with crayon or felt marker, 
then scan for web use. If not scan, shoot a high resolution picture with 
camera or cell phone.

Most any drawing program will use publicly available boundary data and 
create a Mercator projection but I despise that projection and won't 
allow my customers to use it.

Its really tough to use a raster map and to fit grid boundaries to it. 
I'm sure that if I was to root in my data files I could find all the 
state boundaries and county boundaries and draw a US map with Canada and 
with grids marked and identified in a .GIF format that could be ingested 
by GIMP or photo shop. Used to be my program was arbitrarily limited to 
5000 pixels per line and unlimited lines (limited by available 
memory),but I may have expanded that so that weather details smaller 
than 1 km can be drawn on a nationwide map.

Maps in jpeg tend to be messed up when rescaling the size because jpeg 
is better at compressing continuous pictures than lines. In my program 
once I have the drawing commands gathered (which I probably have for 
states, but not grids) making different sizes is trivial, but takes a 
separate program run for each size. The .gif format is limited to a 
pallet of 256 colors, but my drawing program uses 24 bit color numbers.

KM0T probably has access to one of the engineering GIS programs that 
have been created since I did the software for weather data. They come 
in various complexities, usually with princely prices for creation 
seats, but free viewers.

I've searched some of my archives and uploaded a couple maps to an 
accessible server. These don't have grids yet. I don't know where their 
command files are but could look for them someday. Look at:
www.geraldj.networkiowa.com/maps

73, Jerry, K0CQ

On 10/18/2010 1:10 AM, Bruce Richardson wrote:
>
>
> I think this was brought up before but what systems/methods do
> some of you use to make images of "grids already worked" maps?  I
> know KM0T has some nice ones on his website.  I'm thinking of .jpg
> images that I can send along in emails or post on the web.  I have
> some skills with GIMP (kinda like photoshop but different :-) ).
> So I can do that--but with me it's usually tedious :-) .  Do any
> of you use automated systems?
>
> Thanks,
> Bruce Richardson W9FZ
>
>
> "When the going gets weird, the weird turn pro." - Hunter S.
> Thompson
>
>
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