I read article about restricted voronoi diagram. In chapter 3.4 Exact predicates I saw the following: "sideA, sideB, sideC are rational fractions of low-degree (resp. 2, 4/2 and 6/4)." sideA - should return side of point from plane. How rational fraction can help in this problem? Rational fraction and rational function are the same?
Link to the article https://hal.inria.fr/inria-00547790/document