#### Re: Point hit in a circuit

Hello, watchmaker, you wrote: SVZ>> If all of us still about Vatti there it is used sweep line. And in it there is a sorting. If about something another specify, about what. W> I about that is unimportant as am arranged inside Vatti and that he there demands is not related algorithm. Not clearly what for it to the determination task the point in a circuit lies-whether. You resulted a picture which "works" inside Vatti. Therefore and talk about it. SVZ>> As far as I understand, at first it is necessary to calculate winding from each side of an edge (i.e. already additional procedure turns out), and then, sorting out edges, to define, to what area we get. W> it is not necessary to invent anything is it is not necessary. W> Do as in Wikipedia it is written or as already in an adjacent branch told: let out from a point a ray in any direction and consider number of its intersections with a circuit, considering a circuit direction (i.e. +1 or-1 for directions against and clockwise, accordingly). This number also answers about an accessory of a point to a polygon. SVZ>> count that check if the point is outside of a circuit returns: SVZ>> If the ray is launched, as nearby it is offered, from (-inf, py) in (px, py) check returns hit in a circuit. W> s = 0 - that is the point is out of a circuit in any interpretation from above-stated (odd, nonzero etc.). Everything, you understood about what. It is necessary to consider only a direction of an input of an edge in a ray. Confused a mention winding'. I thought that depth a circuit enclosure (0,1,2 is considered... On a picture). Yes, such method looks , than couples/ODD NUMBERS.