Mesh from Lines - Grasshopper2024-03-29T09:58:13Zhttps://www.grasshopper3d.com/forum/topics/mesh-from-lines?groupUrl=weaverbird&commentId=2985220%3AComment%3A1501792&x=1&feed=yes&xn_auth=noHi Milos! How have been work…tag:www.grasshopper3d.com,2016-04-05:2985220:Comment:15017922016-04-05T22:25:51.296ZAyuna Mitupovahttps://www.grasshopper3d.com/profile/AyunaMitupova
<p>Hi Milos! How have been work on ce<span>ll recognition progressing? Is there any news on a new release of evevoronax? </span></p>
<p>Hi Milos! How have been work on ce<span>ll recognition progressing? Is there any news on a new release of evevoronax? </span></p> I don't have my original sear…tag:www.grasshopper3d.com,2014-06-17:2985220:Comment:10894292014-06-17T12:15:13.140ZGiulio Piacentinohttps://www.grasshopper3d.com/profile/GiulioPiacentino
<p>I don't have my original search anymore. It was also a little disappointing. I think there's more. But this might help you with keywords.…</p>
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<p>I don't have my original search anymore. It was also a little disappointing. I think there's more. But this might help you with keywords.</p>
<p><a href="http://www.researchgate.net/profile/Alfredo_Ferreira2/publication/2933997_Polygon_Detection_from_a_Set_of_Lines/file/79e41507ddec7cc0ae.pdf" target="_blank">http://www.researchgate.net/profile/Alfredo_Ferreira2/publication/2933997_Polygon_Detection_from_a_Set_of_Lines/file/79e41507ddec7cc0ae.pdf</a></p>
<p><span>Giulio</span><br/><span>--</span><br/>Giulio Piacentino<br/>for Robert McNeel & Associates<br/>giulio@mcneel.com</p> Thanks,
I`ll think about the…tag:www.grasshopper3d.com,2014-06-17:2985220:Comment:10892932014-06-17T10:57:24.032ZMilos Dimcichttps://www.grasshopper3d.com/profile/MilosDimcic
<p>Thanks, </p>
<p>I`ll think about the possible options. To answer your question - you use some surface anyway to generate Voronoi/Voronax...so you don't need to fit a surface - there is one already there. Then I do a kind of a brute-force search in the parametric space of the surface and i have to say it works in 99.9% of the cases but I would like to make an algorithm that works for any grid/graph, without the underlying surface.</p>
<p>You say there are papers on the planar search for…</p>
<p>Thanks, </p>
<p>I`ll think about the possible options. To answer your question - you use some surface anyway to generate Voronoi/Voronax...so you don't need to fit a surface - there is one already there. Then I do a kind of a brute-force search in the parametric space of the surface and i have to say it works in 99.9% of the cases but I would like to make an algorithm that works for any grid/graph, without the underlying surface.</p>
<p>You say there are papers on the planar search for bounding regions...do you have some links?<br/><br/>Greetings, </p>
<p>Milos</p> Hi Milos
thanks for posting t…tag:www.grasshopper3d.com,2014-06-17:2985220:Comment:10892892014-06-17T10:26:00.980ZGiulio Piacentinohttps://www.grasshopper3d.com/profile/GiulioPiacentino
<p>Hi Milos</p>
<p>thanks for posting this discussion also here.<br></br>I would be interested in hearing what exactly you mean by "<span>the best one I have involves an underlying surface</span>". Are you trying to fit a surface onto the points first, and then, ultimately, doing a planar search for bounding regions? The are papers for the latter part, but I wasn't very happy about them.</p>
<p>I've looked a bit for some literature for generic faces finders, but could not find one that would fit my…</p>
<p>Hi Milos</p>
<p>thanks for posting this discussion also here.<br/>I would be interested in hearing what exactly you mean by "<span>the best one I have involves an underlying surface</span>". Are you trying to fit a surface onto the points first, and then, ultimately, doing a planar search for bounding regions? The are papers for the latter part, but I wasn't very happy about them.</p>
<p>I've looked a bit for some literature for generic faces finders, but could not find one that would fit my needs (including, for example, finding the mesh for the line-representation of a torus). Maybe there's something out there that I did not find either.</p>
<p>The algorithm I use does not really translate easily to cells, but works fairly well if faces move smoothly on the surface. It's running on the edges and brute-force searching for closing faces around them. Then, it chooses the few paths that bound smaller loops. There are some minor optimizations to diminish the amount of searches and a series of clean-up steps after this, to make sure that the result does not contain duplicate faces, flipped faces, faces that encompass two or more faces, etc.</p>
<p>Another alternative I've coded but was not giving good enough results was a DFS on the edges, and closing faces on the go. However, I think I might still add this, and merge the result, as it was finding some intricate cases where the first method was, unluckily, following wrong twists, and so not giving all results.</p>
<p>Does it help?</p>
<p>Giulio<br/>--<br/>Giulio Piacentino<br/>for Robert McNeel & Associates<br/>giulio@mcneel.com</p>