1. A method for simplifying a complex path, comprising: parsing the complex path into a vector linked-list consisted of linked monotonic vectors; dividing each vector in the vector linked-list into vector segments according to intersection points of the vector with other vectors in the vector linked-list; and extracting from all vector segments the vector segments located on a boundary of a region defined by the complex path, and connecting the extracted vector segments according to their location to obtain a simple path.