Not working when points are a collection of GPS positions (Bug of missing feature?)

[johnjore]

Hi!

I tried to use this on a GPX track, substituting X & Y with lat & lng co-ordinates. I used a tolerance of 0.001 in this example.

This is a small section that's been "optimized":

Original:

For some reason, when it travels in a certain direction, it ends up being a straight line and unmodified in the other direction. The GPX went from 4699 points to 2778 points, but if tolerance value is increased, all it does is have more straight lines, and other areas still appear untouched.

My guess is that the code assumes points are "travelling" from left to right, like a graph, and not any random direction?

[BobLd]

@johnjore I wouldn't expect the ordering of the points to matter, so might be a bug in the code.

Maybe can you try this different implementation https://github.com/BobLd/PContourNet/blob/56255225aca740795ca2156c1ab3e5b6edd8ac56/PContourNet/PContour.cs#L484

I ported the code from another java implementation. In your case you will on care about the methods at the bottom.

[johnjore]

Thanks for quick response. Suspect there is a bug in there then.

I found a different implementation a few min after posting, https://github.com/rohaanhamid/simplify-csharp, and it appears to work correctly on the same GPX.