vb.net point inside polygon

Topics: Windows Forms
Sep 10, 2013 at 10:21 AM
I'm fighting a polygon and I managed to give it a form and a dimension. In order to avoid crossing sides/lines I created and used an algorithm which sorts the points clock-wise. Anyway, I do have some problems:
  1. I fail to determine if a point is inside the area of the polygon (see image here Image). An example or a solution (in VB.NET) will be gratefully appreciated.
  2. My sorting algorithm works 90% of times. Is there any other solution for sorting the points of the polygon in order to obtain a solid define area? The polygons on the maps will have between 3 and 30 points.
  3. I also tried to use circles (as markers) but I failed because I didn't understood how to add the reference to the form constructor.
    My level of VB.NET is medium at best so any clear example or advice will be much much appreciated.