Page 1 of 1

Smmitpost Oversimplifies GPX Tracks

PostPosted: Thu May 19, 2016 4:44 pm
by nader
For example, look at this page:

http://www.summitpost.org/baylor-peak/967975

The map that I have put on the main page shows a lot more twists and turns to my path than what you see if you click on "view Route on Map" that summitpost provides. My GPS measured 8.9 miles roundtrip but I suppose due to oversimplification, summitpost says 8.65 miles.

This can become a problem if you try to download GPX Track for a path where going only a few tens of feet off route may get you in trouble.

Re: Smmitpost Oversimplifies GPX Tracks

PostPosted: Thu May 19, 2016 5:00 pm
by rgg
There might be no real problem for those downloading the GPX file.

The key question is whether it is the the map that simplifies the route, or whether SummitPost does something to the GPX file that you uploaded. I mean, I haven't tested it, but I would be surprised if it were the latter. And as long as the file is the original one, anyone can download it to follow the route. The map that SP uses to show it isn't part of the GPX file, so, simplified or not, it doesn't matter. Provided the file is detailed enough, it's the accuracy of the GPS device to which it is downloaded is important, not Google maps.

Cheers, Rob

Re: Smmitpost Oversimplifies GPX Tracks

PostPosted: Thu May 19, 2016 7:08 pm
by Josh Lewis
Google Earth detects the GPX file as 8.37 miles which is even less. :? What does it say when you download the file from your page onto your GPS? We might get a different result.

Re: Smmitpost Oversimplifies GPX Tracks

PostPosted: Thu May 19, 2016 7:54 pm
by nader
Interesting,

Are you saying if I download it back into my GPS I may get a different number? I will try that then when I get the time.

Thank you rgg.

Re: Smmitpost Oversimplifies GPX Tracks

PostPosted: Sat May 21, 2016 6:26 am
by Josh Lewis
nader wrote:Are you saying if I download it back into my GPS I may get a different number?


It's possible depending on if there is any processing to the gpx file upon upload. Photos for example are processed when viewing the original on SP which is why you may notice some changes. If you download the gpx file from your page and it's the same distance as it's supposed to be, then it's an issue with the gpx reader. Otherwise it's the processing of the gpx file.