Question: I just watched a neat video on the perimeter length of an ellipse. What formula/approximation does QCAD use?
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[Answered] Perimeter of an ellipse
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Attach drawing files and screenshots.
Post one question per topic.
[Answered] Perimeter of an ellipse
Last edited by Panchdara on Sun Sep 06, 2020 9:09 am, edited 1 time in total.
Windows 10
Re: Perimeter of and ellipse
Hi,
Ellipse are indeed the tougher ones among the entities.
There aren't closed form solutions.
Talking about perimeter length, what about the others properties ...
Intersections ... Point on ...
Well, I would not know.
Andrew can tell you that.
So, I keep lurking.
Regards,
CVH
Ellipse are indeed the tougher ones among the entities.
There aren't closed form solutions.
Talking about perimeter length, what about the others properties ...
Intersections ... Point on ...
Well, I would not know.
Andrew can tell you that.
So, I keep lurking.
Regards,
CVH
Re: Perimeter of and ellipse
QCAD uses Simpson's Rule as approximation for ellipse arc lengths.
Re: Perimeter of and ellipse
Thankx
CVH
CVH
Re: [Answered] Perimeter of an ellipse
Yes, thanks Andrew. Number of iterations? Or is that dependent on particular setup/specifics of the drawing (such as ellipse ratio)? (I think if I tried to read the code, it'd be like looking for a needle in a haystack )
I am just curious as I had just watched an entertaining video on the subject.
Best regards
Hugh
I am just curious as I had just watched an entertaining video on the subject.
Best regards
Hugh
Windows 10