  We study rational cuspidal curves in projective surfaces. We specify two
criteria obstructing possible configurations of singular points that may occur
on such curves. One criterion generalizes the result of Fernandez de Bobadilla,
Luengo, Melle--Hernandez and Nemethi and is based on the Bezout theorem. The
other one is a generalization of the result obtained by Livingston and the
author and relies on Ozsvath--Szabo inequalities for $d$-invariants in Heegaard
Floer homology. We show by means of explicit calculations that the two
approaches give very similar obstructions.
