turf.tin's result polygons do not fulfill convexhull of points

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I believe, the result polygons of turf.tin must fulfill convexhull of given points. (If my understanding is mistake, please point out.)

But, in some case turf.tin’s result polygons do not fulfill convexhull of given points.

Example data is: https://gist.github.com/kochizufan/63feb2d8843c7cbd9ca9bd48b00c7d38 and output of var output = turf.tin(input, 'target'); is: https://gist.github.com/kochizufan/8f92d389b2a39c68ba0288aa74518e7c This result do not fulfill convexhull of input’s.

Is this bug?

[stebogit]

@kochizufan it seems you’re using points in Mercator projection, which make your data invalid for the library:

In fact Turf expects coordinates in WGS84 projection. You can use the new @turf/projection.toWgs84 method for the conversion (and then, if you need, the complementary @turf/projection.toMercator):

var out = turf.tin(turf.toWgs84(__yourinput__), 'target');

This the result: https://gist.github.com/anonymous/dab8fed1cfb4cac2a204a42e65deef4d

BTW @DenisCarriere it seems @turf/projection has not been added to the latest release.

[rowanwins]

Closing due to inactivity and as this isn’t really an issue with turf.