3-pt arc also has a strange behavior on the axes, but this is not dangerous because it is noticed immediately. it is rather rare in daily work. but can't hurt if it gets cleaned up
[solved] (Dangerous) behavior from the sketcher
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- thomas-neemann
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Re: [workaround] (Dangerous) behavior from the sketcher
Re: [workaround] (Dangerous) behavior from the sketcher
Thx for feedback. At least all OSes behave the same, which is great.
Actually the more I think about it and the more I think current behavior is not so bad.thomas-neemann wrote: ↑Wed Jul 28, 2021 8:31 am 3-pt arc also has a strange behavior on the axes, but this is not dangerous because it is noticed immediately. it is rather rare in daily work. but can't hurt if it gets cleaned up
Regarding 3-pt arc, I think everything's actually correct. 1st and 2nd click are (real) endpoints, and 3rd click is a curve path.
Regarding 3-pt circle, I was fooled by the "name". We actually use points to define the circle, but all these points will have no real existence once circle is created and all that will remain is a curve. So we are actually manipulating a curve, and constraints are (pretty correctly) suggested as such.
Just I don't see why tangent constraint isn't suggested for 2 first clicks but only for third. My own opinion would be to suggest tangent for all 3 clicks (in regard of another curve) because I see no other sensible constraint between a circle and another curve.
Thoughts ?
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Re: [workaround] (Dangerous) behavior from the sketcher
As long as the impression is not created that freecad has caught something even though it did not do it, everything is ok and no unnoticed errors can occur.
Re: [workaround] (Dangerous) behavior from the sketcher
I can't implement such a vague thing. I can change behavior, but I need to precisely know what is expected.thomas-neemann wrote: ↑Wed Jul 28, 2021 10:06 am As long as the impression is not created that freecad has caught something even though it did not do it, everything is ok and no unnoticed errors can occur.
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Re: [workaround] (Dangerous) behavior from the sketcher
i had the problem with referencing a step model. i didn't know the dimensions of the step model. When it was caught, circle 3 pts lit up the external geometry in yellow, so that I thought he caught it. but it didn't and the geometry that i then restricted was wrong.openBrain wrote: ↑Wed Jul 28, 2021 10:21 amI can't implement such a vague thing. I can change behavior, but I need to precisely know what is expected.thomas-neemann wrote: ↑Wed Jul 28, 2021 10:06 am As long as the impression is not created that freecad has caught something even though it did not do it, everything is ok and no unnoticed errors can occur.
later i noticed that when catching no restriction symbol appeared, like with all others e.g. arc, line, rectangle etc. with which it works wonderfully.
Re: [workaround] (Dangerous) behavior from the sketcher
It doesn't help. My proposal is : for all 3 clicks, point-on-line with a vertex, tangent with a curve (any type). Would that be OK?thomas-neemann wrote: ↑Wed Jul 28, 2021 10:28 am i had the problem with referencing a step model. i didn't know the dimensions of the step model. When it was caught, circle 3 pts lit up the external geometry in yellow, so that I thought he caught it. but it didn't and the geometry that i then restricted was wrong.
later i noticed that when catching no restriction symbol appeared, like with all others e.g. arc, line, rectangle etc. with which it works wonderfully.
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Re: [workaround] (Dangerous) behavior from the sketcher
in my opinion this is a good solutionopenBrain wrote: ↑Wed Jul 28, 2021 10:35 amIt doesn't help. My proposal is : for all 3 clicks, point-on-line with a vertex, tangent with a curve (any type). Would that be OK?thomas-neemann wrote: ↑Wed Jul 28, 2021 10:28 am i had the problem with referencing a step model. i didn't know the dimensions of the step model. When it was caught, circle 3 pts lit up the external geometry in yellow, so that I thought he caught it. but it didn't and the geometry that i then restricted was wrong.
later i noticed that when catching no restriction symbol appeared, like with all others e.g. arc, line, rectangle etc. with which it works wonderfully.
Re: [workaround] (Dangerous) behavior from the sketcher
+1
Yellow highlight is not enough. The small symbols are important.
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Re: [workaround] (Dangerous) behavior from the sketcher
I submitted a PR : https://github.com/FreeCAD/FreeCAD/pull/4945
See it in action below (on a simple test case) : My only concern is that (believe me, but you can see it in the file diff of the PR), tangent constraint had been specifically removed for 1st and 2nd click. It was explicit in the code, but there was absolutely no explanation about the reason. And as far as I can think about it, I see no good reason why it could be harmful. If one can figure it out, please let me know and I will pause or kill the PR.
See it in action below (on a simple test case) : My only concern is that (believe me, but you can see it in the file diff of the PR), tangent constraint had been specifically removed for 1st and 2nd click. It was explicit in the code, but there was absolutely no explanation about the reason. And as far as I can think about it, I see no good reason why it could be harmful. If one can figure it out, please let me know and I will pause or kill the PR.
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