Thread: Data in SQL (.db) files

merlinboy, thanks for your efforts.
It looks like the Garmin people did some 'interesting' things.
In an attempt to understand what they did, I converted the Garmin binary coordinates for the Sonnblick trail and created waypoints for the 30 org_pnt/dst_pnt (origin point/distant point) pairs in BaseCamp.
The waypoints are in the following archive (around 3 kB):

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They are labeled 01O through 30O for the origin points, and 01D through 30D for the distant points (origin points are green, distant points are red).
Since a hike normally starts at the trailhead, the waypoint numbering starts with 01O/01D at/near the trailhead.
Of course, all waypoints are on the Sonnblick trail.
The first surprise is that the trailhead waypoint is distant point 01D (as if you were hiking back to the trailhead; origin point 01O is around 40 m up the trail).
The distances (in m) between origin point and distant point for the waypoint pairs vary quite a bit:

Code:

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Up to the 21O/21D waypoint pair, the distant point is closer to the trailhead than the origin point (as if you were hiking out).
For the 22O/22D and 23O/23D waypoint pairs, the origin point is closer to the trailhead than the distant point (as if you were hiking in).
For the 24O/24D through 28O/28D waypoint pairs, the distant point is closer to the trailhead than the origin point (as if you were hiking out).
For the 29O/29D and 30O/30D waypoint pairs, the origin point is closer to the trailhead than the distant point (as if you were hiking in).
At the moment I have no idea why Garmin did it this way.

It is possible that (for their purposes) it does not matter which point in a waypoint pair is called origin point or distant point.
When I tried to create a 'New Route' from the trailhead to the end of the Sonnblick trail, BaseCamp produced a route that was slightly different from the 'named' Sonnblick trail.
On my second attempt I added some intermediate points, and the resulting route was identical to the 'named' Sonnblick trail.
This (together with the 'switching' of origin and distant points) makes me think that the origin point/distant point pairs in the trail_segs (trail segments) table possibly only serve as via points (or 'guiding' points) for their routing algorithms (to make sure that they produce a route that follows the real 'named' trail).
Since the distances (in m) between origin point and distant point for the waypoint pairs vary so much, using only the waypoints for creating tracks or routes would lead to significant errors (deviations from the real trail coordinates).
I think only some routing algorithms in combination with the waypoints in the trail_segs (trail segments) table (and of course the trail lines from the corresponding maps) can produce accurate tracks or routes.
We have the waypoints in the trail_segs table (and the maps, of course).
How do we get the routing algorithms?

Is there a way to use BaseCamp's algorithms for our purposes?
Could we somehow get the waypoints for a given trail into BaseCamp and ask it to create the route for us?
Or, even better (because we could simply select the 'named trail' and let BaseCamp do its thing):
Since BaseCamp is creating the route (just in a different color) when you ask it to display one of the 'Named Trails', could there be a way to 'capture' this route information?
In order to be displayed, this information must exist somewhere in the system (I think).
They must create the 'named trail' route somewhere in the system. Then they probably call a 'display route' routine to display it.
(At least, that is how this non-expert sees it. Could be wrong, of course.)