Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!usc!ginosko!uunet!cbmvax!mitchell From: mitchell@cbmvax.UUCP (Fred Mitchell - QA) Newsgroups: comp.graphics Subject: Re: Intersection between a line and a polygon (UNDECIDABLE??) Keywords: P, NP, Jordan curve separation, Ursyhon Metrization Theorem Message-ID: <8058@cbmvax.UUCP> Date: 2 Oct 89 22:50:50 GMT References: <2972@ndsuvax.UUCP> <32610@cornell.UUCP> Reply-To: mitchell@cbmvax.UUCP (Fred Mitchell - QA) Organization: Commodore Technology, West Chester, PA Lines: 10 A simpler way of thinking about it is to: 1) compute the plane the polygon lies in 2) calculate the point where line intersects plane 3) determine if point lies inside or outside of polygon. A possible way of determining 3) would be to do a bounding box around polygon and if point lies outside bounding box, you know that its outside. If in, you've more checking to do. Since I have done this in the Ray-Trace package I'm currently working on, drop me E-mail if you want more details.