Swapped edges on loft

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triplus
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Re: Swapped edges on loft

Postby triplus » Thu Jan 28, 2016 11:59 pm

Yes it would be great if user would be able to control Loft orientation at sections. I remember when Ruled surface didn't have orientation control:

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viewtopic.php?f=3&t=2337

User couldn't do much about it. After if i remember correctly Werner added Orientation property:

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User could control behaviour in all conditions. But it wasn’t trivial commit if i remember correctly therefore i am guessing much work would be needed to add user section control for Loft feature. But then again that would take Loft feature to that next level we all hope for it will get someday.
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Kunda1
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Re: Swapped edges on loft

Postby Kunda1 » Fri Jan 27, 2017 2:34 pm

soft bumping to ascertain the status of issue #2508.
Thanks!
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Kunda1
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Re: Swapped edges on loft

Postby Kunda1 » Sat Jun 03, 2017 3:52 pm

Ref ticket:issue #2508
Abdullah wrote:ping
Is this a PDN blocker?
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chrisb
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Re: Swapped edges on loft

Postby chrisb » Wed Jun 07, 2017 6:39 am

Kunda1 wrote:
Sat Jun 03, 2017 3:52 pm
Ref ticket:issue #2508
Abdullah wrote:ping
Is this a PDN blocker?
Definitely not, because the behaviour is the same in 0.16 and 0.17. It isn't a bug, not even an issue. The documentation states
This means that if one is doing a loft between two squares, the maximum twist possible is <45°.
F2 is twisted 45° so the twist is expected.
chrisb
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Re: Swapped edges on loft

Postby chrisb » Wed Jun 07, 2017 7:30 am

I am always unsure how to handle the discussion. Should I enter comments in the ticket as well?
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Kunda1
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Re: Swapped edges on loft

Postby Kunda1 » Wed Jun 07, 2017 12:23 pm

chrisb wrote:
Wed Jun 07, 2017 7:30 am
I am always unsure how to handle the discussion. Should I enter comments in the ticket as well?
Yes please. Thx!
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chrisb
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Re: Swapped edges on loft

Postby chrisb » Wed Jun 21, 2017 9:41 am

Since this is more a discussion topic I don't enter it in the bugtracker:
(quote from the tracker)
abdulla wrote: It is as a PDN blocker as it is a Part blocker, i.e. the same issue happens in PDN.
A blocker is (to me) an issue prohibiting roll out of a stable version. Since the behaviour exists for years, probably since Loft exists, I don't think it should block v 0.17.
I am not sure that profile is overtwisted (as per documentation). I would tend to think that if the one half of the arc was possible, the other half should be possible as well.

What I understand from the documentation is that if the twist would me more than 45º, the selection of correspondance would change so as to minimize the twist.
The documentation is clear about angles < 45° degrees. They are not twisted. That may imply that for angles >45° the loft has to be twisted, because the opposite angle is less than 45° degrees. Alas, the docs say nothing about an angle = 45°, and that's what we have here twice. So it boils down to a precision issue, one of the angles being less and one being greater than 45° degrees. The only thing we could do to make it unique is to prohibit lofting if an angle=45° is recognized.
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Kunda1
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Re: Swapped edges on loft

Postby Kunda1 » Wed Jun 21, 2017 10:56 am

DeepSOIC wrote:ping
@abdullah pinged you in the ticket asking if you can weigh in? Thanks in advance!
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DeepSOIC
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Re: Swapped edges on loft

Postby DeepSOIC » Wed Jun 21, 2017 3:34 pm

Kunda1 wrote:
Wed Jun 21, 2017 10:56 am
...
Sorry, I'm afraid I can't say anything useful yet. Edge order decision is likely upon OCC. AFAIR there is a method to enforce a certain edge-to-edge relationships in OCC API, but I'm not sure.