Cutting unusual shape into cylinder

I’m trying to add a micro USB hole to a cylinder, I can do a circular hole in a cylinder easily enough but this one isn’t quite as “clean” as I’d like it to be…

Any ideas?

Subdivide the edge ring?

I mean this warping, it’s subtle but I was hoping for some close renders. I can tidy the lip I think without too much trouble.

Top row: structure without subdivision surface (SDS)
Middle row: SDS result
Bottom row: SDS result with highly reflective surface
Columns: left is SDS with supports only, middle is SDS result with 100% creasing, right is SDS result with corrected normals

The closer the support structure needs to be, the more vertices around. There will be distortion with subdivision, but it’s easier to deal with when the curved surface consists of more or less square faces, and the face size to the supported corners change gradually.

That’s because SDS averages two points on an edge (using approximation), which creates more distortion the further away it has to do it on a perfect curved surface, which will require a grid structure for a perfect reflection. A sudden change in face size, or in other words edges/vertices close together, will create a sharp detail.

If the remaining distortion on the SDS result is not good enough to give an illusion of a perfect surface, which it would be noticeable with highly reflective surfaces, one way to deal with that is to have another object without the detail and get the normals from that surface.

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