OpenEuphoria

polygon intersection

• Posted by Lewis Townsend <keroltarr at HOTMAIL.COM> Jul 03, 2001
• 340 views

Hello Everyone!

Here in the near future I am going to need a function to find out where on a 
polygon a ray (or line-segment) will intersect given the starting point of 
the line and either the ending point or a directional vector of the same 
line and the points on a polygon. I would want this function to return 0 
(zero) if the line did NOT intersect the polygon and the {X,Y} coordinants 
of such an intersection if it did. Here is a skeleton function for this:

function Intersect( atom x1, atom y1, atom x2, atom y2, sequence poly )
  return {x,y}
end function

I need this function to be as fast as possible. I can think of a few "brute 
foce" methods to accomplish this but nothing that would be efficient. As I 
implied above the x2,y2 can define a directional vector or an ending point. 
Just pick whichever format can be used to produce the fastest results. If 
anyone can do this I would be very grateful. I don't need it right now but 
might in a day or two.

thanks in advance,
Lewis Townsend
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