point outside a non-convex shape I have a non-convex shape (object) in black on the figure on the link. At the beginning, All red points are outside the shape. Next, I apply a random transformation on some points. This create a new shape (yellow). 
What I want is to fill the outside of the shape with a specific color but because of the transformation, some red points are now inside the shape. I would like to know how to find a correct red point, i.e outside the shape to apply the filling algorithm.
Here is the link on the image.
http://postimage.org/image/sbjmgi1tr/

In that case, use a point in polygon algorithm. Then you can test each point if it is in your new polygon or not.
