mapbox / mapbox/vector-tile-spec

1st ring is negative area

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Description

Hello.
I'm trying to parse tile [20524.vector.pbf.zip](https://github.com/mapbox/vector-tile-spec/files/553002/20524.vector.pbf.zip) (mapbox streets v6) and one of the polygon feature has the first ring with negative area.

Layer: id=2, name=building
Feature: id=4
Geometry: 0x0009 0x153E 0x058C 0x001A 0x00C9 0x00BB 0x04BC 0x050F 0x017A 0x0000 0x000F
Ring: (2719 710) (2618 616) (3224 -32) (3413 -32)
Area: -126149

What does it mean? How should I handle that?
Vector Tile Spec says that 1st ring of polygon (`ExteriorRing`) must have a positive area.

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Research direction

Review the Vector Tile Spec's polygon ring and area rules against the supplied layer 2, feature 4 geometry and its listed ring coordinates. Determine whether the negative first-ring area is valid or indicates an ambiguity in the specification, and document the expected interpretation or handling guidance.

Written by the indexing model from the issue text.

Assessment

Domain
documentation
Issue type
Documentation
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
28/100

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