what's the difference between ring and polygon in boost geometry? -

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i'm new boost geometry , confused ring , polygon. in documentation, there's no figure showing ring, , polygon. can draw figure explaining difference between 2 concepts?

thanks in advance.

in boost.geometry polygon defined areal geometry containing exterior ring , number of interior rings (holes).

ring represents 1 of polygon's rings. it's different ogc linearring because it's areal geometry. when used alone can seen polygon without holes.


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