Extend surface flips blend

[eobet]

Before:

After:

File:

extend-flips-blend.3dm (154.8 KB)

[martinsiegrist]

Try _HistoryPurge

[eobet]

I think you’re missing the point.

History should just work.

In fact, I can’t think of a simpler example where it should just work…

[martinsiegrist]

Got it… Something must be wrong.

PS: maybe change your title to “Extend surface breaks blend with history”…

[pascal (Pascal Golay)]

I believe this is fixed in the WIP. I will check.

-Pascal

[eobet]

Nope, I just confirmed… it’s very much not fixed.

I have 7 blends in a fairly simple design that I’m trying to do rapid design iteration on… and it is not very rapid at all… and yes, it affects ALL of them! Repeatedly! Even if you re-do one, and then extend again, the same thing happens!

[wim (Wim Dekeyser)]

Hi Robert -

@eobet

Nope, I just confirmed… it’s very much not fixed.

I’ve added this thread to RH-70644 ExtendSrf: changes edge indices
-wim

[eobet]

This is adjacent, not sure if it deserves its own thread or not but before trim:

And after trim:

No reason for any of the unaffected edge IDs to change (and just to pre-empt the inevitable technical answer: Yes, I know a trim curve goes all around even untrimmed edges in Rhino but as an end user I simply don’t care… that’s a technical debt McNeel engineers have to clean up).

mutual-trim-blend.3dm (170.1 KB)

[sach]

I’ve also noticed this:

Extend Surface w/History - Surfaces Break

In this example, the child surfaces break when the parent is modified using the extend surface tool. They are fine when transforming the main surface using move, scale, move control points) Version 7 SR22 (7.22.22255.5001, 2022-09-12) ext srf breaking.3dm (214.5 KB) [ext srf breaking]

[Gijs (Gijs de Zwart)]

The edge indices issue with ExtendSrf will be better in upcoming 8.13. There is still an issue with this particular file, which I logged here:
RH-83958 ExtendSrf twists or pinches BlendSrf

[brian (Brian Gillespie)]

RH-70644 is fixed in Rhino 8 Service Release 13

[eobet]

I just checked for updates and ended up on SR14 which produced this:

[martinsiegrist]

Looks like this in Rhino 8 todays build and Rhino 9 WIP

[Gijs (Gijs de Zwart)]

That particular issue is still open (RH-83958), the one fixed is RH-70644

[sach]

I noticed extend surf took my blend curve and shifted it to the opposite end of the surface. !
In the latest 8 build

[wim (Wim Dekeyser)]

Hi Sach -

@sach

I noticed extend surf took my blend curve and shifted it to the opposite end of the surface. !

Please post the 3dm file.
-wim

[sach]

I’ve lost track of when it happened. I’ll try and send it when I next come across it.