, it has the ability to deal well with large files. I haven't needed to change line endings, at least for me it figures it out when opening the file (I've never built a navobj.xml from scratch, could be you have to make adjustments to do that).
Each track should start with something like this:
<trkpt lat="-40.791023000" lon="172.954091667">
<trkpt lat="-40.791022833" lon="172.954154833">
note the <trk>
that's the tag that defines the beginning of each track. Each track ends with </trk>
In all of my files tracks are the last objects stored, although I don't know if that is always the case. Anyway,
- Open both your old and your current navobj.xml in Notepad++
- Search the old file from the top down for the first <trk>
- Mark that location
- Go to the very end of the file and search upward for the last </trk> (if it is like mine it will be the next to last line in the file)
- Copy all the data between your first mark and the last </trk> (including both the <trk> and </trk> tags)
- Go to the new file and get your cursor to the very end of the file.
- Search upward for the last </trk> in the new file
- Place your cursor after the last </trk> and put in a new line ('Enter' on a Win box).
- Paste the stuff you copied from the old file.
If the tracks are the last thing in the file then the very end of the new file should be:
indicates the end of the last track, then the </gpx>
indicates the end of the data in the file. For it all to work
right the old tracks should start with a <gpx> and end with a </gpx> and should not interrupt any of the similar pairs in the new file (hope that's clear).
Having said all of that, tracks can be memory (and disk) hogs, the more of them OpenCPN has to load the more memory it takes and it can really slow things down. Don't know about a full-size Win box, we run 'O' on a Raspberry Pi 3 and I find myself doing the opposite about once a year, I extract a year's worth of tracks and store them as a backup in case I ever want them. That greatly reduces the navobj.xml size and speeds up 'O' loading and most actions (panning, zooming, etc.).