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cnr-isti-vclab / meshlab

The open source mesh processing system
http://www.meshlab.net
GNU General Public License v3.0
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Convert tri mesh to quad-dominant mesh: missing trias #1392

Open yvanblanchard opened 1 year ago

yvanblanchard commented 1 year ago

Hello,

I have a case where turning trias to quads does not entirely well: there are many remaining trias that could (visually) be merged to quads (see images, before and after applying the filter). NB: Of course, the equilateral triangles in the middle of three branches are expected to be kept.

I tried other optim modes but not better (fewest triangles, etc). I used meshlab version 2022.02.

image image

Here is the input STL file as well. trimesh-example.zip

GiovanniSer commented 1 year ago

I downloaded the stl file to parse it but its not stl it is obj With STL I can check if the floating point leads to points that are not exactly coplanar. STL uses floating in single precision and it can happen to believe equal points which are not equal I've never used MS quads but a face should have all points coplanar. Only Autocad admits ambiguous faces of non coplanar points. Ambiguous because they can then be represented with two different pairs of triangles.