pub fn union_soup(
rings: &[Ring],
tolerance: Tolerance,
) -> Result<Vec<Polygon>, OverlayError>Expand description
Union a set of individually-valid rings that may overlap each other.
overlay rejects a self-intersecting operand, which is correct for a
boolean between two shapes but wrong for a union of a triangle soup: a
projected mesh routinely overlaps itself, and mutual overlap is exactly
what a union is for. Each ring is still validated on its own, so malformed
geometry is refused rather than absorbed.