Please set "Rtklib quality" from imported NMEA track fixtype (gpx:fix)

[grinapo]

I have summarized the general problem in https://josm.openstreetmap.de/ticket/20601#comment:4 but here's a temporary (as in "until the proper fix coloring gets implemented, which, considering the minimal reaction on the half dozen issues may take a long time") quick solution, which would be really simple to implement (I'm no java wizard, that's why I don't start with a patch, but by the looks of it it should be really simple).

NMEA import already process fix info ("gpx:fix") but it's not used in track display (hdop is close to useless for many RTK based streams). (Converting to OSM layer has multiple problems, so that is not a solution.)

There seems to be already a quality coloring scheme: "Rtklib quality".

It would be really useful to convert fix type to rtklib quality number (in case that it's not already defined), like:

rtk=1
float rtk=2
dgps=3
3d=4
2d=5
all the rest=6

(if I understand correctly that quality 1 is best)
which would make it possible to color them right away.

[Bjoeni]

Closed as duplicate of #20600.