Trying to write a sub or function to verify if a point is included whitin the shape defined by several 2D points

[hhxman]

What I am trying to do is to define a formula, or even a function that can be able to answer if a certain point (Xp, Yp) is or not included within a shape defined by several points (not always the same number of points).
Graphically is simple to answer if You can easily plot the shape.
In a cartesian chart i can represent the shape which is delimited by the perimeter defined from the position of the several points (X1, Y1), (X2, Y2) ... (Xn, Yn). Does the point P = (Xp, Yp) belong to the area of the above defined polygon? Does the point P eventually belong to the edge?

Thanks in advance,

hhxman

 

[sijpie]

google on
determine if point is within polygon

you will get loads of answers