Hi Brent, so yes "naked" edges (edges that only belong to one face instead of being joined between 2 faces) are not good for meshing because the mesher does extra work on joined edges to make sure the mesh vertices have a common watertight structure there.
On naked edges each edge gets vertices generated all on its own and that can make for little cracks in the mesh structure.
re:
> So then I'm wondering what operation will connect those?
It's the Edit > Join tool. To try and rejoin something already partially joined like you have here you would first need to use Edit > Separate to break the object into individual surfaces and then you can select it all and attempt a new join.
However edges need to be within a pretty tight tolerance of each other to be joinable. If the model is not very accurate with too much of a gap between 2 edges that can prevent join from working.
One trick that can help is to scale the model down before doing the join.
In your case here if you select the object, then run Edit > Separate, then run Transform > Scale and in the Scale command type 0 <enter> to use 0,0,0 for the scale origin and then type in 0.01 <enter> to scale it down by 1/100 in size, then Edit > Join and then Scale up by 100 (repeat previous steps but use 100 for scale factor).
In your case here that reduces the number of naked edges from around 700 to 100 and does seem to get the one you were asking about. I tested using the v5 beta which you can get at https://moi3d.com/beta.htm .
That should get rid of any actual cracks in that spot. You still may not like the generated mesh in that area though because the UV quads that are generated at the start of the meshing process are kind of close to each other, this situation tends to make for some skinny triangles. To tune this you could export using n-gons instead of triangles (it's good to view the n-gon structure even if you want to output triangles because it shows you what is the base polygons that are being triangulated) or also use the "Divide larger than" mesh parameter to dice up the UV quads a little more first before trianguilation, try something like Divide larger than = 5 or Divide larger than = 2.
- Michael |
