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Negative areas #3

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SymbolixAU opened this issue May 21, 2018 · 1 comment

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SymbolixAU commented May 21, 2018

Some areas are negative

library(sf)
nc <- st_read(system.file("shape/nc.shp", package="sf"))

library(googlePolylines)
library(boostgeometry)

enc <- encode(nc)
wkt <- polyline_wkt(encode(nc))
bg_area(wkt$geometry, strategy = "geographic")
sf::st_area(nc)

Has to do with winding, but, why are the already considered 'correct'?

bg_area(bg_reverse(wkt[98, 'geometry']), strategy = "geographic")
bg_area(bg_correct(wkt[98, 'geometry']), strategy = "geographic")

Collaborator Author

SymbolixAU commented Jun 1, 2018

My example seems to be related to googlePolylines precision : SymbolixAU/googlePolylines#23

SymbolixAU closed this as completed in

7964c12

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