Andrew DeVries
06-08-2008, 11:51 AM
I am currently working on an APRS plug-in for Storm Lab. Its a stand alone executable that monitors the APRS data stream (internet or TNC) and creates a GIS file. You then add the Gis file as an overlay file in Storm Lab and set the update rate to match the setting in my executable. This allows our skywarn Net control operator to see the positions of our Spotters with the weather data on the same screen.
The hardest part was writing a parser for the APRS packets to extract the LAT and LON since there are about a million ways it can be sent via APRS. I found some public GNU source code from the APRS World project but it has a lot of extra stuff if you will in the message parser and it was in written in C. for Linux. I am coding in Managed .Net so I need to rewrite it to C# or VB. Mostly Syntax and Library call changes but its for the best as rewriting gives me a better understanding of the APRS protocol.
What the real goal here would be to allow a two way communication between Net Control and the stations in the field using APRS. This would allow the Net Control operator to send a APRS object such as "Possible Rotation" here as a Funnel Cloud Icon. This object would then appears as an Icon on the spotters screen and because it is relative to his position he can position himself/herself to get a better look.
Every thing is in place in Storm Lab to allow this using APRS and GIS files.It even allows for custom icon files in the GIS file. What is missing from Storm Lab is a way to create shapes or Icons on the current displayed map. A very quick and simple option would be to right click on the map and have the menu option to copy Lat, Lon to the Clipboard.
With this simple feature it would allow me to use my executable to have the operator past the lat, lon ,and pick an Icon, add some text and introduce it to the APRS data stream as well as his GIS file. This would display it on everyones Storm Lab map.
I also plan to extend it to allow for the transfer of radar images to mobile stations via APRS. The plan is to emulate a custom web server locally and use the APRS network to supply the radar images. As Storm Lab allows the radar images to be pulled via http I can emulate a http server in my executable and serve up the radar images from my emulated web server built into my plug-in.
I still am not sure how well sending the radar images will work at 1200 baud yet but I suspect it will be better to run a separate 9600 baud APRS network dedicated to Skywarn to keep from busying up the national APRS network on 144.390.
Anyways my immediate need is to have ability to have the LAT/LON copied to the local computer clipboard via a right click on the map or a keyboard shortcut.
Thanks
Andy
KC8MHK
The hardest part was writing a parser for the APRS packets to extract the LAT and LON since there are about a million ways it can be sent via APRS. I found some public GNU source code from the APRS World project but it has a lot of extra stuff if you will in the message parser and it was in written in C. for Linux. I am coding in Managed .Net so I need to rewrite it to C# or VB. Mostly Syntax and Library call changes but its for the best as rewriting gives me a better understanding of the APRS protocol.
What the real goal here would be to allow a two way communication between Net Control and the stations in the field using APRS. This would allow the Net Control operator to send a APRS object such as "Possible Rotation" here as a Funnel Cloud Icon. This object would then appears as an Icon on the spotters screen and because it is relative to his position he can position himself/herself to get a better look.
Every thing is in place in Storm Lab to allow this using APRS and GIS files.It even allows for custom icon files in the GIS file. What is missing from Storm Lab is a way to create shapes or Icons on the current displayed map. A very quick and simple option would be to right click on the map and have the menu option to copy Lat, Lon to the Clipboard.
With this simple feature it would allow me to use my executable to have the operator past the lat, lon ,and pick an Icon, add some text and introduce it to the APRS data stream as well as his GIS file. This would display it on everyones Storm Lab map.
I also plan to extend it to allow for the transfer of radar images to mobile stations via APRS. The plan is to emulate a custom web server locally and use the APRS network to supply the radar images. As Storm Lab allows the radar images to be pulled via http I can emulate a http server in my executable and serve up the radar images from my emulated web server built into my plug-in.
I still am not sure how well sending the radar images will work at 1200 baud yet but I suspect it will be better to run a separate 9600 baud APRS network dedicated to Skywarn to keep from busying up the national APRS network on 144.390.
Anyways my immediate need is to have ability to have the LAT/LON copied to the local computer clipboard via a right click on the map or a keyboard shortcut.
Thanks
Andy
KC8MHK