Problem with constraints based sketcher

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Kunda1
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Re: Problem with constraints based sketcher

Postby Kunda1 » Wed Aug 26, 2020 7:04 pm

abdullah wrote:
Tue Aug 25, 2020 2:57 am
(tag = "flipping" or "jumping" or "solver can tell right from left")
I think creating a tag or 2 would be enough, no?
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Roy_043
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Re: Problem with constraints based sketcher

Postby Roy_043 » Wed Aug 26, 2020 8:02 pm

Often a 'flipped' sketch has undesirable intersections or T-joints. Maybe this could become a setting or option?
abdullah
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Re: Problem with constraints based sketcher

Postby abdullah » Sat Aug 29, 2020 2:06 am

Kunda1 wrote:
Wed Aug 26, 2020 7:04 pm
abdullah wrote:
Tue Aug 25, 2020 2:57 am
(tag = "flipping" or "jumping" or "solver can tell right from left")
I think creating a tag or 2 would be enough, no?
Sure. That is what I meant (well probably it was on my mind only ;) )
chrisb wrote:
Tue Aug 25, 2020 6:00 am
I wouldn't create a new category, but we may add links to one of the existing tickets, e.g. issue #4279. They are all closed though, because flipping is not considered to be a bug.
IMO, it is not a "bug" unless the behaviour is inconsistent (today it goes right, tomorrow it goes left). It could be a "feature" to avoid unwanted licit behaviour. The tagging is intended to enable investigation to see if there is some solution, at least for some subgroup of cases.

By way of example, one very common source of problems is programmatic constraint datum change from a spreadsheet, maybe a new functionality could be provided that limits the rate of change making successive smaller solves (this is in line with the mechanism for avoiding jumping while dragging). Such a functionality may not be acceptable for normal sketching as it might affect latency, but it may be acceptable for a spreadsheet change (or it may even turn out to be acceptable for normal use after testing it).

Maybe we end up with a subset of "local minimum selection" techniques which improve user experience...
Smiling_user
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Re: Problem with constraints based sketcher

Postby Smiling_user » Sat Aug 29, 2020 2:41 am

there should be a solution like [Preserve relative angle] or [Preserve relative direction]
chrisb
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Re: Problem with constraints based sketcher

Postby chrisb » Sat Aug 29, 2020 6:31 am

Smiling_user wrote:
Sat Aug 29, 2020 2:41 am
there should be a solution like [Preserve relative angle] or [Preserve relative direction]
That's what the tickets say, and what the various discussions are all about.
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Smiling_user
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Re: Problem with constraints based sketcher

Postby Smiling_user » Sat Aug 29, 2020 8:11 pm

Then what is the approximate difficulty to solve? What approaches are already checked for solving?
At least this problem is inside the proper code of FC or it comes from external dependency?

In practice did the same: small steps iteration to change a sketch through dd.dd value.
Another experience was a certain approach in setting dependencies / constraints in the sketch of "pockets", so that on the change of the base detail - pockets remain normally positioned.

Besides, is there a place to see the whole graphical map of FC code structure?
(like... kernel, modules, UI, BL, dependencies to OpenSCAD, python etc.)