The number of shape vertices.
When the vertex count is zero, the shape is defined implicitly. If the vertex count is greater than zero, the shape is explicitly defined by its vertices.
Defines how the vertex winding of polygon contours is interpreted (outer rings vs. holes):
+/- 1 for polygons,
0 for non-polygon shapes.
A polygon contour is classified as an outer ring or a hole according to the sign of its signed area:
outer := sign(Area(contour)) == Parity hole := sign(Area(contour)) != Parity
The default value is
-1 (i.e. clockwise orientation in a standard Cartesian coordinate system).