Due to a pet project of mine that involves mapping, i've downloaded
played around with it a little, and considered my options with it.
working on an offroad 'carputer' for my car linked up to a gps
planning on using freely available road & elevation data from the USGS
(maybe a few
others just for kicks - ortho/pictures, land cover, hydrology, etc).
Given this data, i'd like to be able the following:
-given some GPS coords, load in the corresponding map data consisting
of the various
formats. I'd like to do some system where it only loads in the map
data for the
immediate area, and as I drive along the old data (from where I had
been) would be
dropped and more data would be streamed in. I don't have a huge amount
of memory, so
i need to keep the size of in-memory processes small.
-then with the map data in memory at the moment, i'd like to do various
it. For instance, i would like to ask geotools for something like
features in specific spots (ie up ahead) so i can have other functions
certain questions (what is my expected elevation? what elevation is
coming up ahead?
is there drop offs or cliffs? roads? streams? etc etc). elevation data
won't be so bad, since I just need to figure out how to access the grid
memory. since roads are probably in some sort of vector format, i
figure that if i
want to know what roads are several hundred yards ahead of me i'll have
through all roads in memory to figure out which are nearby.
i'm not very familiar with mapping, but after looking around it seems
shapefiles are common formats for roads, streams & rivers, and
so i guess i'll use the ShapeFileDataStore (and various readers) as per
code snippets. then for elevation, probably some DEM or NED (probably
in GeoTIFF or
ArcGrid format, since they are supported by Geotools). i'm not as sure
since Geotools 2.0.0 doesn't seem to be as established on this - one
snippet i found on the website is labeled "Could not get working".
so i guess if anyone had any pointers on this sort of thing, I would
love to hear
what people think. i'm sure for the experts this is a pretty simple
task, but for us
neophytes it takes some work to just get the basics up and running.
tip can save me hours of struggling with it!
-Mike Gordon mike.gordon@...