0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

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abdullah
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0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

Postby abdullah » Tue Oct 16, 2018 2:56 pm

Moderators: Not sure where you would like to have this. Feel free to move it to another subforum.

I write to ask for user input regarding this feature. Something is telling me that is not working as expected, but I am not sure what I would like to have.
FilletArcOfConics.gif
FilletArcOfConics.gif (85.07 KiB) Viewed 549 times
Does this look like what is requested?
GeneFC
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Re: 0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

Postby GeneFC » Tue Oct 16, 2018 3:52 pm

Not sure what was "requested", but that would be a nice feature.

I have always made that sort of shape with three arcs connected using end-to-end tangency. This new method would be easier.

Gene
RogerK
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Re: 0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

Postby RogerK » Tue Oct 16, 2018 3:54 pm

Hi abdullah

In my point of view it's exact the expected result when you filet two arcs. The result is similar as when you do this with just two lines. Great that you have implemented this.

What other result can you imagine, when you filet two arcs? What makes you worry about your current implementation?


Kind regards

Roger
abdullah
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Re: 0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

Postby abdullah » Tue Oct 16, 2018 4:47 pm

GeneFC wrote:
Tue Oct 16, 2018 3:52 pm
Not sure what was "requested", but that would be a nice feature.
RogerK wrote:
Tue Oct 16, 2018 3:54 pm
In my point of view it's exact the expected result when you filet two arcs. The result is similar as when you do this with just two lines. Great that you have implemented this.
I am not sure exactly what is requested. I am not sure this is the way (tm). Curves are trickier than segments, as curvature keeps changing. It also admits a plurality of intersections. I am struggling to consistently get the same result. But it is good to see that what is shown is what is expected.
RogerK wrote:
Tue Oct 16, 2018 3:54 pm
What other result can you imagine, when you filet two arcs? What makes you worry about your current implementation?
One initial problem I had was related to the fact that curvature keeps changing, so it is very relevant where you click the segments. I had also to restrict to curves that (if extended) intersect.

As of now, it does not work segment with arc of conic. It does not work with B-splines. Sometimes I am still getting a very wrong result. See:
FilletArcOfConics2_ok.gif
FilletArcOfConics2_ok.gif (250.55 KiB) Viewed 531 times
FilletArcOfConics2_fail.gif
FilletArcOfConics2_fail.gif (254.3 KiB) Viewed 531 times
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Kunda1
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Re: 0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

Postby Kunda1 » Tue Oct 16, 2018 4:52 pm

ooh, I bet @joel_graff (who's working on the Transportation Engineering WB) would dig this thread
Joel_graff wrote:
Last edited by Kunda1 on Tue Oct 16, 2018 5:43 pm, edited 1 time in total.
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chrisb
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Re: 0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

Postby chrisb » Tue Oct 16, 2018 5:43 pm

Does it work as well with just clicking the corner?
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Joel_graff
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Re: 0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

Postby Joel_graff » Tue Oct 16, 2018 8:09 pm

That's really awesome. Nice that it's integrated into the existing tool, too - eliminates the need for geometry checking.

I wrote a monstrous amount of python code to achieve this same effect, but my results were exact. Still, this is a lot easier than anything I'd imagined.

Thanks for the great work!
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bejant
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Re: 0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

Postby bejant » Tue Oct 16, 2018 10:47 pm

abdullah wrote:
Tue Oct 16, 2018 2:56 pm
Does this look like what is requested?
Yes, you nailed it - thanks abdullah!

To me it looks like the size of the Fillet is determined by where the user clicks on the two existing arcs (maybe you alluded to that in your next post) - is that right?


abdullah wrote:
Tue Oct 16, 2018 4:47 pm
It also admits a plurality of intersections.
In the event that multiple possible intersections exist, I think the user would expect the Fillet to be created near to where the cursor picks happened on the parent curves.


abdullah wrote:
Tue Oct 16, 2018 4:47 pm
Sometimes I am still getting a very wrong result.
I wonder, do the directions in which the Arc and Arc Of Ellipse were originally created (clockwise or anti-clockwise) come into play there?

Thanks again abdullah; it's good to see you back coding again!
chrisb
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Re: 0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

Postby chrisb » Tue Oct 16, 2018 10:58 pm

bejant wrote:
Tue Oct 16, 2018 10:47 pm
To me it looks like the size of the Fillet is determined by where the user clicks on the two existing arcs (maybe you alluded to that in your next post) - is that right?
Thats how it works with straight lines.
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bejant
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Re: 0001304: Allow Sketcher to Fillet Arcs, Not Only Lines

Postby bejant » Tue Oct 16, 2018 11:03 pm

Yes, but I'm asking about the curves...