Originally Posted by capolaris09
How are you? I'm interested in using OpenCPN, and was wondering if this software
can open up a file from a web site (GPX or KML) with gps
points (markers) and overlay them on a chart.
Since the online file will be updated every 5 minutes with new markers, can OpenCPN automatically refresh its display in real time in order to show all the markers as the online file gets updated?
O understands how to import
GPX files and convert to a route
. There is a import
file dialog box for this feature.
But it does not know how to download GPX files from a user defined web site. What you can do is write a plugin similar to the Venture Farther plugin to automatically import the new GPX file into the routes and waypoints database. I think this would require a few changes to the base program (not hard) and some nifty plugin code writing. The plugin API knows how download files using Curl. That's what the chart downloader uses. So the hard part is already there.
Alternatively, one could write a separate program (or shell script) to periodically download the GPX files. Then a very simple plugin could inform O to import the new GPX files silently. This would probably be the easiest and fastest way.
Once the waypoints are imported they will show up in their correct geo location on the chart. O recently had an update to address slow performance with hundreds or a few thousand waypoints. If you plan to import many thousands of waypoints in a small area there could be performance issues again. We would have to test on some of the weaker CPU platforms.
But first, explain more what exactly you want to do. Maybe there is another already existing solution.