On Wed, Feb 1, 2012 at 12:27 PM, Roy Stogner <royst...@ices.utexas.edu> wrote: > > > On Wed, 1 Feb 2012, John Peterson wrote: > >> A related question is: do we want contains_point() to return "true" in >> cases where the point is definitely outside the element (to within >> floating point tolerance), but is "inside" the element (to within >> user-specified tolerance)? > > > My first inclanation is to say no, but I'm not sure.
I'd like to say "no" as well. The reason I ask is that, if I understand correctly, the folks doing contact here have been using contains_point() as I described above with relatively large (larger than TOLERANCE) tolerances to detect when a point is at least "nearby" the element. For linear elements, the TOLERANCE bounding box checks must have been causing contains_point() to return "false" more often than they otherwise would have wanted... >> If no: then contains_point() probably shouldn't accept any >> user-specified tolerance at all. > > > This I'm not so sure about. Think of the user-specified tolerance as > just a way for users to *shrink* the false-positive region if they > need to, rather than a way to grow it. So by "false-positive region," do you mean the size of the bounding box used in the first-order element optimization? If that's the case, we should 1.) actually use the user-specified tolerance in the bounding box tests, not TOLERANCE 2.) Give the parameter a more descriptive name and document its purpose better. 3.) Use TOLERANCE/10 and TOLERANCE for the inverse_map() and on_reference_element_calls(), respectively (?) -- John ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Libmesh-devel mailing list Libmesh-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmesh-devel
