Hi OSTexo, thanks for posting that VSR blend - that's one of the best star type blends that I've seen. There is no hint of lumpiness between adjacent left-right neighbors of the filling surface, so it doesn't have the kind of residual star pattern artifact that seems to be usually present in this kind of blend.

The main quality problem that I see with it is that it has a somewhat flat-ish shape through most of it and it kind of has a bit of a sudden bend in it right when it comes to the outer boundary. This is interesting since with other star blend mechanisms it's this area that is actually well shaped.

Also the surfaces generated by VSR are very light - they are higher degree (degree 5) single span surfaces instead of cubics. This is a fairly different kind of structure than the regular star blend mechanism which is usually based off of making degree 3 Coons patches for each surface. I think that VSR is kind of specialized in its focus on working with single-span surfaces, undoubtedly some general techniques coming from ICEM Surf coming into play there.

It's not exactly perfect but I think it does show that the star blend mechanism is not necessarily 100% fatally flawed.

Using only single span surfaces would probably have some downsides in other situations though, like if you were trying to fill in a hole where the edges were sort of wiggly and not so uniformly shaped a single span surface would probably not match up very well then...

- Michael