We're dealing with country borders, that is the set of multiple disjoint domains that is made of polygons. 

To extract the different point on the map by a given country we've been said to implement the [ray casting algorithm][1] which is absolutely fine, but the country is hardly to be the simply-connected domain. For example, the Italy consists of many disjoint domains (islands). 

In this case the crossing number algorithm or the even-odd rule algorithm is still a valid approach to validate if the point in question is within the country borders or not?

**EDIT**

After days of research finally found one discussion: [MySQL implementation of ray-casting Algorithm?][2] which gives the exhausting number of links, answers and code snippets to implement the algorithm in code (Pseudo-code: http://rosettacode.org/wiki/Ray-casting_algorithm).

Thanks!

  [1]: http://en.wikipedia.org/wiki/Point_in_polygon
  [2]: https://stackoverflow.com/questions/7573881/mysql-implementation-of-ray-casting-algorithm/13196590