mapbox / mapnik-vector-tile

Mapnik implemention of Mapbox Vector Tile specification
BSD 3-Clause "New" or "Revised" License
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Positive Orientation #164

Closed flippmoke closed 8 years ago

flippmoke commented 8 years ago

Changed the output winding order of the polygons such that they always have a positive orientation for exterior rings. Currently we were strictly enforcing CCW exterior rings for vector tiles but since they are in screen coordinates with the y axis downward -- this causes the winding direction visually to change from CCW to CW. However, the orientation would still be positive with a CW winding order in a vector tile.