[mapserver-users] Tracking vehicles, Displaying positions

[Carmelo Saffioti]

Hi Brent,
thank you very much for your really interesting suggestions.

> 1. Just display the GPS points of the required vehicles in the map.
> 2. Run a query to turn the required points into a linestring on the fly &
display the line.
> 3. Pre build vehicle tracklines according to business rules and display
selected lines in the map.

- these pre-build vehicle tracklines are every possible street on which any
vehicle can move on? (1) could be the solution. How come (2) and (3) are
faster?


> You also haven't said whether you want web maps or hard copy maps. I'm
assuming you are looking at web maps for now, & can print the result if
required.

- I need web maps


> The other issue is that the map needs some background to give your data
context. If necessary you can assemble local datasets of roads,
aerial/satellite imagery, etc to overlay your data on. However I suggest you
consider OpenLayers to provide the maps in your web application. This gives
you easy access to Google & OpenStreetMaps & a range of public WMS/WFS data
as a background without having to manage these data yourself.

- It could be a good idea, but I don't think that exists any map of the zone
I need, because it's a private area, not a public street. So, a public map
could have not every possible street in the zone. On GoogleMaps I saw that
the map of this zone is about 3 years old.


> Using Postgis to manage your spatial data, mapserver to provide it as a
web service & OpenLayers as the client in your application, actually putting
the various layers together to build your map is a very effective toolset
for the sort of thing I think you are trying to achieve.
>
> If you do need local vector data in addition to your GPS data, then I
don't think CAD is the way to go, as suggested by other respondents,
extracting these into GIS formats is going to work better for you in this
arena.

- So, do you suggest to extract the DWG planimetry into Postgis tables? If
yes, before extracting the DWG, do I need to make it georeferenced?


Thank you again for your help
Cheers
Carmelo





> Hi Carmelo,
>
> I am doing prettyt much this for vessel positions using PostGIS databases
instead of MySQL. I believe PostGIS offers more mature & substantially
better support for spatial objects at present, but you can probably achieve
similar results with MySQL.
>
> From a data management and display perspective, I suggest you consider
three approaches depending on your needs:
>
> 1. Just display the GPS points of the required vehicles in the map.
> 2. Run a query to turn the required points into a linestring on the fly &
display the line.
> 3. Pre build vehicle tracklines according to business rules and display
selected lines in the map.
>
> All are relatively simple to do with PostGIS & Mapserver, and can be
managed with MySQL, although I don't think as easily. (We use mostly option
3, and also option 2, opion 1 is a bit limited & can be somewhat slower to
display)
>
> You also haven't said whether you want web maps or hard copy maps. I'm
assuming you are looking at web maps for now, & can print the result if
required.
>
> The other issue is that the map needs some background to give your data
context. If necessary you can assemble local datasets of roads,
aerial/satellite imagery, etc to overlay your data on. However I suggest you
consider OpenLayers to provide the maps in your web application. This gives
you easy access to Google & OpenStreetMaps & a range of public WMS/WFS data
as a background without having to manage these data yourself.
>
> Using Postgis to manage your spatial data, mapserver to provide it as a
web service & OpenLayers as the client in your application, actually putting
the various layers together to build your map is a very effective toolset
for the sort of thing I think you are trying to achieve.
>
> If you do need local vector data in addition to your GPS data, then I
don't think CAD is the way to go, as suggested by other respondents,
extracting these into GIS formats is going to work better for you in this
arena.
>
> HTH,
>
>    Brent Wood
>
>
> --- On Wed, 11/5/08, Carmelo Saffioti <csaffi at libero.it> wrote:
>
> > From: Carmelo Saffioti <csaffi at libero.it>
> > Subject: Re: [mapserver-users] Tracking vehicles, Displaying positions
> > To: "Venkat Rao Tammineni" <vtammineni at roulacglobal.com>,
mapserver-users at lists.osgeo.org
> > Date: Wednesday, November 5, 2008, 11:39 PM
> > Thank you Venkat for your reply,
> > it's interesting to know that it's possible to
> > access coordinates data
> > directly from the MySql db...
> > but before displaying points on the map, I need to
> > understand how can I
> > "create" a map from my planimetry DWG cad file...
> >
> > I hope you can help me
> > Cheers
> > Carmelo
> >
> >
> > Hi,
> >
> >    1)There are different ways to place GPS points on map.
> >      a)  You can display points using OGR direct
> > connection, Please refer
> > below url
> >
> > http://mapserver.gis.umn.edu/docs/howto/ogrmysql/?searchterm=ovf
> >
> >
http://mapserver.gis.umn.edu/docs/howto/debian-odbc-mysql/?searchterm=ovf
> >
> >
http://mapserver.gis.umn.edu/docs/reference/vector_data/VirtualSpatialData/?searchterm=ovf
> >
> > 2)And You can not create DWG file by using mapfile.Mapfile
> > will give you
> > image format.
> > Please have a look below url.
> >
> >
> > http://mapserver.gis.umn.edu/docs/reference/vector_data/format_types
> >
> > I hope this helps you.
> >
> > Thanks,
> > Venkat
> >
> >
> >
> > From: mapserver-users-bounces at lists.osgeo.org
> > [mailto:mapserver-users-bounces at lists.osgeo.org] On Behalf
> > Of Carmelo
> > Saffioti
> > Sent: Wednesday, November 05, 2008 2:30 PM
> > To: mapserver-users at lists.osgeo.org
> > Subject: [mapserver-users] Tracking vehicles, Displaying
> > positions
> >
> > Hi everybody,
> > I need to develop a system for tracking and displaying
> > vehicles
> > positions. I'm storing NMEA gps sentences into a MySql
> > DB. Now I'd
> > like to display these positions on a map. How can I do?
> > I'm new to
> > this, can you give me any suggestion?
> > I have to create the map too, because this zone is not
> > mapped. Is it
> > possible to create a map from a DWG cad file?
> >
> > I hope you can help me
> > Cheers
> > Carmelo
> >
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