small improovement for getResampledBySpacing

[jonasfehr]

To avoid bigger gaps at the end of the resampled polyline, adding almost a full spacing will help adding a rather small last space than a big one. The last point is replaced anyway.

[ofTheo]

Thanks for this!
I actually ran into this bug recently where we were doing large spacing and couldn't figure out the big gap at the end of a resampled poly.

I was also trying to figure out why your fix worked as it didn't quite make sense at first ( going over the total length of the line ), but as you said it moved the last point to be where the last point of the original line is which can create the big gap.

I think this might be a slightly cleaner fix - replacing the move of the last vertex with an add of the last vertex. it has the same visual effect but avoids doing extra calculation in the for loop.

    float f=0;
    for(f=0; f<totalLength; f += spacing) {
        poly.lineTo(getPointAtLength(f));
    }
    
    if(!isClosed()) {
        if( f != totalLength ){
            poly.lineTo(points.back());
        }
        poly.setClosed(false);
    } else {
        poly.setClosed(true);
    }

For reference here is how it looked before your PR:

And with your fix and the fix I suggested above:

[jonasfehr]

A more elegant solution, indeed. It just needs <= in the for-loop to work if the spacing is an accurate fit, as if you use getResampledByCount. float f=0; for(f=0; f<=totalLength; f += spacing) { poly.lineTo(getPointAtLength(f)); } if(!isClosed()) { if( f != totalLength ){ poly.lineTo(points.back()); } poly.setClosed(false); } else { poly.setClosed(true); }

…

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On 27 Aug 2019, at 06.53, Theodore Watson ***@***.***> wrote: Thanks for this! I actually ran into this bug recently where we were doing large spacing and couldn't figure out the big gap at the end of a resampled poly. I was also trying to figure out why your fix worked as it didn't quite make sense at first ( going over the total length of the line ), but as you said it moved the last point to be where the last point of the original line is which can create the big gap. I think this might be a slightly cleaner fix - replacing the move of the last vertex with an add of the last vertex. it has the same visual effect but avoids doing extra calculation in the for loop. float f=0; for(f=0; f<totalLength; f += spacing) { poly.lineTo(getPointAtLength(f)); } if(!isClosed()) { if( f != totalLength ){ poly.lineTo(points.back()); } poly.setClosed(false); } else { poly.setClosed(true); } For reference here is how it looked before your PR: <https://user-images.githubusercontent.com/144000/63741873-99cd9400-c84b-11e9-8f22-66ab1d04e708.gif> And with your fix and the fix I suggested above: <https://user-images.githubusercontent.com/144000/63741881-a3ef9280-c84b-11e9-8b33-5d1e85780226.gif> — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#6361?email_source=notifications&email_token=ABON6ZIGPKGFQFR6GDVFB7DQGSXK7A5CNFSM4IPRCA6KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD5GPDOI#issuecomment-525136313>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABON6ZJXKBAYM6KAYJG4NMLQGSXK7ANCNFSM4IPRCA6A>.

[ofTheo]

Ah yes :)
Looks good - thanks!!