I've been experimenting with some heuristics to reduce the number of points generated by the Route-From-Track function in the Route
A very simple approach seems to work fine:
- to include the waypoint, if its XTE between the Accepted Previous Point, and Potential Next Point exceeds "TrackPoint Distance Interval" / 2.
- to include the waypoint every (x * "Plan_Speed" Nautical Miles, x=2.0 seems OK, equivalent to 2 hrs underway = half a watch)
Both parameters are settable in respective Dialogs (TrackPoint Distance Interval: Tools/Etc, Plan_Speed: RouteProperties).
Some example results:
1. A track of 3028 trackpoints recorded every 60 seconds is reduced to a 40 waypoint route
by choosing PlanSpeed=3.0, TrackDist=0.05 (minimum possible)
2. A track of 6682 trackpoints generated from LOGBOOK timestamps every 30 minutes is reduced to a 540 waypoint route by choosing PlanSpeed=10.0, TrackDist=0.5
3. A tricky track of 272 trackpoints recorded every 60 seconds is reduced to a very reasonable route of 25 waypoints by using default values of 6 kn and 0.1 nm.
This algorithm tends to smooth out gentle curves rather than look for positively straight lines. There are many other approaches possible, and none is objectively perfect ...
For programming simplicity I am omitting the very last stretch of route, but manual checking and and touchup is always necessary on such routes anyway.
PS. Note the Zero increase in user interface here ...