[algogeeks] Re: Fortune's algorithm for Voronoi diagrams

2006-11-29 Thread Quintopia
I've found an implementation that uses whether bc is a 'right turn' from ab as its sole corvergence criterion (where a b and c are sites in neighboring regions). The code it uses is: if ((b.x-a.x)*(c.y-a.y) - (c.x-a.x)*(b.y-a.y) 0) --~--~-~--~~~---~--~~ You

[algogeeks] Re: Fortune's algorithm for Voronoi diagrams

2006-11-29 Thread Quintopia
I just tested it . . .right turn detection did the trick. so there's your answer. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to

[algogeeks] Re: Fortune's algorithm for Voronoi diagrams

2006-11-28 Thread Quintopia
Better answer for #1 that I'm pretty sure will work: calculate the center and radius of the circle. if the radius is not NaN (i.e the sites are not collinear) and the center of the circle is between the current locations of the breakpoints, they will converge. On Nov 21, 6:36 am, bordaigorl

[algogeeks] Re: Fortune's algorithm for Voronoi diagrams

2006-11-28 Thread Quintopia
Also, in response to your idea, it doesn't make sense. . .you calculate the center of the circle BY calculating where the bisectors intersect. Or vice versa. The two values are always equivalent. Also, your fear about numerical instability is unfounded. Calculating the orthocenter by bisector