prichterich
commented
1 year ago There are lots of fields in NAV-PVT sentences that could be useful in other sports. None of those are needed for speedsurfing, and they all would increase the size of the file format, so they will not be added to the minimal format. Adding the two fields you mentioned would increase the file size by 20%, with zero gain for the current purpose. For sports like skydiving, the increase in actual file size would likely be significantly larger since compression overflows would be much more frequent.
The original plan was to make the gpy format extendable. Implementing this would allow the storage of arbitrary other data, but it would also make the parsers more complicated. The actual gain would be somewhat limited, at least with respect to the EPS logger, since anyone interested in other applications can simply log in ubx format.
After analyzing the GPY files in the latest version of GPS results there were 2 fields empty: (Alt[m] and [knts]) .
When I checked with Manfred Fuchs he indicated that these fields (height and vertical speed) are not stored in GPY. Although for speed windsurfing I don't believe this is a relevant field, but for other sports (skiing, sky-diving, ...) it might be very valuable. As this is an open-source format, it is a valuable field. I don't think the file-size would increase a lot having this field available.
I also don't know if the field need to be used once available and if it is not used by the GPS logger, if the file size would even grow at all.
Manfred did point out that it does require an update of the software once enabled.