On 24-07-17 17:02, Willem Ferguson wrote:
I have done quite a bit of testing of the software in land.
2) Logging did not occur at 3 min intervals, but at about 5-min
intervals. The software behaves almost like the minimum allowed
between-record interval is 5 minutes and it substitutes my 3-min
interval with 5-min.
This 5 minutes seems in line with the code. See core/gpslocation.cpp
line 89. As is this hard coded, and there is only one gpsLocation
instance that never has its update frequency set to anything else than
the initial 5 minutes, there seems at least a coupling with the QML UI
missing.
I think there is room for experimentation with the algorithm that does
the GPS recording. I suspect that a single plot is obtained from several
GPS data points and the criteria for determining an accurate plot are
set quite tight so that data points need to be very close together for
the software to record a single GPS position in the list of GPS
positions. If this is the case, then one should experiment with the
number of repeat points required for a single GPS position as well as
the degree to which these repeats need to be similar in order to be
accepted as a valid GPS record. This is the only way in which I can make
sense of this.
Trying to understand the code, I do not see any resampling of GPS data
points. It is, currently, just a sample every 5 minutes (for the
location service).
For a manual add of a dive, we can select "use current position", and
that pulls an update of the position independently of the 5 minute mark.
This seems an obvious spot where work needs to be done. As we are (for
the lucky ones with BT/BLE or FTDI interfaced DCs), moving away from
manual input, we need a way to add a position to a downloaded dive.
Looking through the mobile app ... I do not see this functionality yet.
I scratched around in the mobile-widgets, core and Qt-models directories
to look for the code where the actual GPS recording takes place but I
have not yet found it. I am not sure at what low level the GPS chip is
accessible from our code.
Ok, as said above. core/gpslocation.cpp.
--jan
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