Clipping on GO.touches(p1, p2)

[asinghvi17]

Consider 2 polygons for which GO.touches(p1, p2) == true. In this case, the intersection is generally understood to be a linestring.

Two questions arise:
(a) GeometryOps currently returns an empty polygon for intersect(p1, p2). Should we allow it to return a LineString if the target is set to GeometryCollection? If so, how would that work with the current Foster algorithm?
(b) Do we need to check intersection dimensionality first before constructing the intersection?

[asinghvi17]

This could be solved if we implement the JTS OverlayNG methods which are specifically for these kinds of cases. But they're a bit slower than Foster, so we need to watch out for that. Offering OverlayNG as an algorithm is definitely an option.