A/P - Point is on boundary of polygon. Orientation algorithms (including CGAlgorithmsDD) fail by incorrectly reporting the point to not be on the boundary. See https://trac.osgeo.org/geos/ticket/841 POLYGON ((0 0, 1 0, 0 1, 0 0)) POINT (0.95 0.05) false L/L - Line A contains Line B. Fails due to imprecision of computed self-node in A. See https://trac.osgeo.org/geos/ticket/572 LINESTRING (1 0, 0 2, 0 0, 2 2) LINESTRING (0 0, 2 2) true