Hi, I’m noticing what seems like a bug in the render mesh that is creating naked edges which don’t appear if I create a mesh from the same valid polysurface with the same mesh settings. I’m currently using a custom render mesh, but discovered this issue initially with the default ‘Jagged and Faster’ render mesh settings. I’ve tried reproducing this using several other files and one I created specifically from scratch to try and replicate the issue (shown below).
On the right is the polysurface, in the middle is the extracted render mesh (with naked edges) and on the left is a mesh created from the polysurface with the same mesh settings that the render mesh is set to:
Here is the detailed info of the poly mesh:
Here is the detailed info of the extracted render mesh:
Here is the detailed info of the mesh created from the polysurface with the _Mesh command using the same mesh settings:
Here’s the geometry I created specifically to test this. The valid polysurface is on the left, the extracted render mesh is in the middle and the meshed polysurface is on the right. Only the extracted render mesh has naked edges (28).
It seems it may have something to do with _FilletEdges as I’m not able to reproduce the issue if I just create a simple box, however the mesh construction seems to be different in general between the render mesh and the general _Mesh and shows in the _What dialog. The _Mesh command creates a ‘Closed double precision polygon mesh’ while the _ExtractRenderMesh just states that it’s an ‘Open polygon mesh’. Maybe if it was closed it would say other wise, but thought I would point this out either way.
This all probably wouldn’t be an issue, but if you create UVs and export the polysurface as an OBJ you get something like this when you look at the UVs in another app (Houdini):
I am able to run _Mesh on the polysurface (which creates a valid closed mesh) and create valid UVs from there, however it would make my pipeline so much more efficient if the render mesh was behaving the same as _Mesh.
To recreate the issue, create a box, run _FilletEdge and select all of the box edges to round them all off. Then run _ExtractRenderMesh and _ShowEdges. I’m happy to upload a file as well if need be.
I’m currently running Rhino version 6.18.19266.14201 on Windows 10.