This function checks if points lie in a polygon or ellipse.
NumericMatrix, a 2-columns matrix with (x and y) coordinates of the points of interest.
NumericMatrix, a 2-columns matrix defining polygon vertices or ellipse boundaries.
int, used for computation. Default is 1.
1: Trigonometry.
2: Special case = axes-aligned rectangle.
3: Special case = axes-aligned ellipse.
double, epsilon threshold value. Default is 0.000000000001