In the attached file—
Problem Fillet.3dm.zip (454.6 KB)
—I have two polysrfs. The one in purple is the starting point and the one in red is after filletedge, rolling ball, 1" on all the edges in the opening.
This largely produces a closed polysrf but with two issues.
First, it creates two “fins” sticking out for unknown reasons. I have to extractsrf and delete them.
Second, EdgeFillet creates a number of bad surfaces.
brep.m_E[4] edge is not valid.
edge.m_vi[0]=edge.m_vi[1]=3 but edge.IsClosed() is false.
ON_Brep.m_E[4] is invalid.
Rhino surface object is not valid.
brep.m_E[3] edge is not valid.
edge.m_vi[0]=edge.m_vi[1]=0 but edge.IsClosed() is false.
ON_Brep.m_E[3] is invalid.
Rhino surface object is not valid.
brep.m_E[5] edge is not valid.
edge.m_vi[0]=edge.m_vi[1]=1 but edge.IsClosed() is false.
ON_Brep.m_E[5] is invalid.
Rhino surface object is not valid.
brep.m_E[4] edge is not valid.
edge.m_vi[0]=edge.m_vi[1]=0 but edge.IsClosed() is false.
ON_Brep.m_E[4] is invalid.
The bad surfaces do not appear repairable. However, they can be replaced and all works out fine.
In order to create multiple holes, I built a negative of the opening and did filletedge on it. The exact same problems appeared but I only have to fix them once rather than for each hole.
I am puzzled why it would create (1) the two fins and (2) the bad surfaces rather than the typical gaps one gets with problem edge fillets.