relation, intersections := p.Relate(q)
relation.Disjoint()
relation.Intersects()
relation.Equals()
relation.Touches()
relation.Contains()
relation.Within()
relation.Covers()
relation.CoveredBy()
relation.Overlaps()

// convenience functions based on Relate:
p.Touches(q)  // boundaries/interiors intersect (p may overlap or contain/within q)
p.Overlaps(q) // interiors intersect (p may contain/within q)
p.Contains(q) // no boundary/interior is exterior
p.Intersections(q) // return list of intersections