Maybe I’m snowed in looking at the wrong thing, but isn’t the theory that G2 matches the angle between the third row of control points? So where does this dip below come from?
dip-after-match.3dm (931.2 KB)
The iso direction is only from the second row of points… if it also matched isocurve curvature, then the third row I suppose.
-Pascal
Just to make sure we’re counting the same thing:
First row, G0.
Second row, G1.
Third row, G2. Right?
Still can’t understand where Rhino gets the dip from, and of course, manual massaging shows that it’s not necessary:
The starting surface has less curvature - straighter - at the edge than the target surface
So the third row needs to be pulled in to impart that curvature
With curves it might be easier to see
However there are other adjustments that can be made as well - sometimes perferable perhaps, but hard to get right on surfaces it seems to me.
Dunno if that muddies or clarifies.
-Pascal
@eobet I think you can get a better flow if you trim back the green surface slightly (more on the top)
the attached has that followed by blendsrf.
That it benefits from adjustment can be seen if you make a blendcrv on the top edge. It results in an S-curve:
dip-after-match_re.3dm (268.0 KB)
Thanks, I have workarounds and know how to solve it manually (been doing that for more than a decade), I’m just curious about the Match command’s behavior here because I haven’t learned the logic and rules which govern it.
I take it that “match target direction” doesn’t restrict the control point adjustments to normal only, like in Alias for example?
I find MatchSrf performing quite well with tangency only, and I use it for curvature with care. In the long thread VSR end of Life- you’ll find plenty of examples of MatchSrf misbehavior.