Hi Seth, Glad you think it's useful! I did wonder about the robustness of the test against different triangle patterns, but decided to just keep it simple as a demo, as the exact triangle pattern is not specified to be (or not to be) predictable.
One thing this test already threw up is that an hourglass made of two triangles, touching at the apex, triangulates to a single triangle, and the other one in the original polygon is lost. I think for a triangulation-pattern-agnostic "correctness" test, you might consider: * Take every edge in every triangle. Every edge in the original polygon should exist once, every edge found only in triangles should exist twice, once in each direction. * Checking winding direction of all triangles matches the original polygon (if this is a claim the triangulation function makes). Further sanity checks (which are probably technically superfluous but still illustrate the expected geometrical properties): * Check no triangle overlaps any other (also checks no dupes) * Check no triangle "escapes" the polygon (can only happen for concave polygons) * Check the summed area = polygon area (combined with no overlap and no escape, means no gaps inside the polygon) I'll be happy to implement these tests if that sounds sane! This is analogous to the philosophy behind the fillet test, which just checks that the points produced satisfy the expected geometrical constraints, but doesn't prescribe any specific values. Cheers, John On Wed, Dec 19, 2018 at 7:40 PM Seth Hillbrand <s...@hillbrand.org> wrote: > > Am 2018-12-19 10:19, schrieb John Beard: > > Sorry, I failed to rebase that over the newest changes. This should > > apply better as a patch. > > Hi John- > > Thanks for the really useful test harness. I'll have time to look at it > in detail in Jan. Briefly, I have some concerns about testing for > specific triangle outputs as a triangulation can still be valid with > different outputs. I'm not yet sure what kind of test we want here, > perhaps a total area check or something similar. > > I'll give it some thought but if you or others have any ideas off-hand, > I'd love to hear them. > > -Seth _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : kicad-developers@lists.launchpad.net Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
