Author Topic: Wahoo Route track points limit  (Read 1129 times)

quixoticgeek

  • Mostly Harmless
Wahoo Route track points limit
« on: March 18, 2018, 11:34:23 pm »

Does anyone know if there is an upper limit on the number points you can use on a route in a wahoo elemnt bolt? I can't seem to find any hard numbers.

Thanks

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Wahoo Route track points limit
« Reply #1 on: March 19, 2018, 12:05:07 pm »
None I believe, I have created a 200 mile plus route without any issues.

quixoticgeek

  • Mostly Harmless
Re: Wahoo Route track points limit
« Reply #2 on: March 22, 2018, 10:15:06 pm »
None I believe, I have created a 200 mile plus route without any issues.

It's a computer it has an upper limit, just from it's available memory. A 200 mile route can easily have just a few dozen track points (2 is enough for the 90 mile straight through the Nullarbor) , a 200km route can have 4000 track points. Distance isn't the governing factor here, it's how many track points there are.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Wahoo Route track points limit
« Reply #3 on: March 23, 2018, 12:06:55 pm »
As I say, I haven't found it yet and I have hundreds of routes on mine, including best bike split ones which contain hundreds to thousands of trackpoints because they are power targets that change every few hundred yards

Re: Wahoo Route track points limit
« Reply #4 on: November 04, 2018, 06:47:39 pm »
Hi guys
I asked the following question to Wahoo Fitness Support :

Hello
How many trackpoints can the ELEMNT BOLT handle per GPX file ?
Some apps (example WIKILOC**) offer to limit to 500 trackpoints in order "to ensure compatibility with most GPS devices", but I would rather have all trackpoints included (3000 - 4000 pts). This is a question asked in several forums, but no one seems to know the answer.
**please add WIKILOC to your associated app list ! :-)


Mike G (Wahoo Fitness Support) answered me with the following :

Hello Jef,
We haven't hardcoded any limit. There is probably a point where it will fail, but likely 10s of thousand of points. Thank you.
Cheers,
Mike G


So there you have it from the "horse's mouth".

Re: Wahoo Route track points limit
« Reply #5 on: November 04, 2018, 08:23:29 pm »
It's a bit of a redundant question these days. Is anybody likely to plot a single route so long that it is going to challenge the waypoint capacity of a modern GPS? I think not. And yes, in practical terms distance is a factor, unless you are riding somewhere so remote as to entail just one road for hundreds of miles.

Those of us that have been at this game for some time will remember gpxx, and be fully aware of why that format is now defunct.

Re: Wahoo Route track points limit
« Reply #6 on: November 04, 2018, 08:39:12 pm »
Is anybody likely to plot a single route so long that it is going to challenge the waypoint capacity of a modern GPS?

People have uploaded whole cross-continent bike rides (i.e thousands of km) into my website as a single GPX file. It's not unusual for modern high-resolution GPS routes to have north of 40 points per km (typical for RideWithGPS). Multiply the two and you're easily into six figures, which would be beyond the claimed "tens of thousands" for the Wahoo. Even something relatively sane like LEL at that resolution might cause trouble.

quixoticgeek

  • Mostly Harmless
Re: Wahoo Route track points limit
« Reply #7 on: November 04, 2018, 09:38:44 pm »
People have uploaded whole cross-continent bike rides (i.e thousands of km) into my website as a single GPX file. It's not unusual for modern high-resolution GPS routes to have north of 40 points per km (typical for RideWithGPS). Multiply the two and you're easily into six figures, which would be beyond the claimed "tens of thousands" for the Wahoo. Even something relatively sane like LEL at that resolution might cause trouble.

I find that with a lot of the modern bike tech there is often an assumption that noone rides more than 6 hours. Noone rides more than a couple of hundred km, and noone rides when it's cold.

This was one of the problems we saw a lot with Garmin's, they would often crash on long rides, as they seem to have not been tested for such long rides.

As for the Wahoo bolt, I did a ride with 18376 track points, and it seemed to cope just fine.

But I'm guessing that the kids at wahoo haven't tested it with 50000 or 100000 track points.

The limit will depend to an extent on how much ram there is in the device. If each track point is 2 x 32bit floating point (reasonable assumption). That's 8 bytes per point. That's assuming it isn't loading into memory a turn by turn. If so, a 10000 point track would be 80kB. Or put another way, if it has 1MB of ram, that's enough for 125000 points. But if you add some data for turn by turn, it's going to get much bigger. I wonder how much ram it has...

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Phil W

Re: Wahoo Route track points limit
« Reply #8 on: November 04, 2018, 10:44:48 pm »
I processed a track with just over 1.4 million track points, and just over 49,000 waypoints today.  If you want to test your Wahoo...

Re: Wahoo Route track points limit
« Reply #9 on: November 04, 2018, 10:53:28 pm »
The limit will depend to an extent on how much ram there is in the device. If each track point is 2 x 32bit floating point (reasonable assumption). That's 8 bytes per point.

If you store lat/long as 32 bit you get obvious visible artefacts when you render the tracks on maps (at least this far from the Equator). You have to use either 64 bit float or maybe fixed point ints.

Quote
If so, a 10000 point track would be 80kB. Or put another way, if it has 1MB of ram, that's enough for 125000 points.

You're assuming they store it in a tight binary format, and not turn every point into an object with lots of lovely overhead.

I'd also be worried more about speed and redraw times than just fitting it all in memory.

Phil W

Re: Wahoo Route track points limit
« Reply #10 on: November 04, 2018, 11:00:50 pm »
You also do not need to hold the whole track in memory at once.