topic Re: Ellipse cannot keep its shape, but turns into a circle in Visualization

Ellipse cannot keep its shape, but turns into a circle

Anonymous — Fri, 26 May 2023 12:55:30 GMT

Hello!

When creating a new profile in Profile Manager, my ellipsoid contour becomes circular.

Here is what I do step by step:
1. Open Profile Manager, create new profile.
2. With Line Tool, I create a rectangle and inside of it a draw an ellipse, also with line tool.
3. Then I select Fill Tool and while holding space bar I click on the rectangle to transform it into filled surface.
4. Next I select that surface, and with Fill Tool selected and while holding Space Bar, I click on the ellipse in order to make an ellipsoid hole in the surface.

But the hole is circular and not ellipsoid.

If I do everything the same, but with a bit bigger ellipse, everything seems to work fine and the hole keeps its ellipsoid shape.

Does someone know why is this happening?

Thank You!

Re: Ellipse cannot keep its shape, but turns into a circle

Dontknow — Sun, 12 May 2019 15:19:04 GMT

It's working over here:

As 4th step try this:
4. Select the Fill Tool, Shift-select the fill and click on the ellips with your Magic Wand (spacebar).

Good luck.

Dontknow

Re: Ellipse cannot keep its shape, but turns into a circle

Anonymous — Sun, 12 May 2019 15:28:24 GMT

Thank you Dontknow for your answer!
But I still can't manage to succeed.
It still seems as if there is some boundary under which the ellipse is too small sized, and it gets approximated to a circle.

Re: Ellipse cannot keep its shape, but turns into a circle

Dontknow — Sun, 12 May 2019 15:48:40 GMT

Made a video of it.
Maybe that will help you.

Re: Ellipse cannot keep its shape, but turns into a circle

Anonymous — Mon, 13 May 2019 09:14:51 GMT

Thank you so much for your help and the video!
Could you check if you can get the same result if you create a big surface and a much smaller ellipse of approximately same sizes as on my attached photo?
Because I can also get the result which you got in the video, if I make a bigger ellipse.

Re: Ellipse cannot keep its shape, but turns into a circle

Dontknow — Mon, 13 May 2019 12:53:51 GMT

Bigger rectangle and small ellipse also gives me a circle as hole!
Must be de precision of the ellipse when it's smaller.

Re: Ellipse cannot keep its shape, but turns into a circle

Anonymous — Mon, 13 May 2019 18:36:38 GMT

Yes, it must be something like that then.
Thank you for checking!

Re: Ellipse cannot keep its shape, but turns into a circle

Dontknow — Tue, 14 May 2019 10:02:35 GMT

What does work is this:
Make a small rectang and a small ellipse.
Make the fill with the elliptical hole and at last make the fill bigger with offset all edges.

Re: Ellipse cannot keep its shape, but turns into a circle

Anonymous — Tue, 14 May 2019 15:11:26 GMT

Hmm, it seems I can't make it work like that either.
I also tried to make it the other way round, big ellipse cut out of the fill, and then offset edges, but i get some irregular ellipse (the other image attached).

Re: Ellipse cannot keep its shape, but turns into a circle

Daniel Kovacs — Wed, 19 Jun 2019 11:11:26 GMT

Hi,

This is not a Complex profile issue, but a magic wand issue.

Fills cannot handle circles and ellipses, they can only handle segments of curves. So if you are to make an elliptical shape in a complex profile, you would need to magic wand the ellipse that you drew with the arc tool, and it will break it down into smaller circular curve segments.

Now, Magic wand can't do this 1 to 1, because it needs to simplify the curves to some extent, so it has a tolerance setting for curves (Deviation from curves) in the "Design>Magic Wand Settings..." menu.
By default this is set to 40, and that basically means, it will be able to simplify ellipses smaller than 40-50 mm by a single circle.

If you go to "Design>Magic Wand Settings...", and change it to a smaller value (e.g. 1), it will be able to create smaller elliptical holes as well. Please note, that it is not recommended at all, to use curves in complex profiles, because they increase polygon counts significantly! (that is one of the reasons it is set to 40 by default).

I hope this solved your issue.

Regards,

Re: Ellipse cannot keep its shape, but turns into a circle

Barry Kelly — Thu, 20 Jun 2019 01:21:31 GMT

dkovacs wrote:
Please note, that it is not recommended at all, to use curves in complex profiles, because they increase polygon counts significantly! (that is one of the reasons it is set to 40 by default).

But if you don't use curves and use many straight line segments instead, then you can't hide the lines between the surfaces in the extruded profile.
Unless I have been missing something all these years.

Barry.

Re: Ellipse cannot keep its shape, but turns into a circle

Daniel Kovacs — Thu, 20 Jun 2019 08:10:10 GMT

Hello Barry,

Yes, you are absolutely right! If you need these big outside surfaces to be smooth, you need to use curves, and that is fine.

But if you have very small parts that are curved in real life (like a reinforcement bar or a metal cable), since they are so small that you will not see the segmentation anyways, it might be worth just drawing them as octagons instead (I sometimes even opt for squares and triangles).

Even in these cases you might still choose to use curves instead, but it is just good to be aware, that the number of polygons will be really high.

Regards,

Re: Ellipse cannot keep its shape, but turns into a circle

Lingwisyer — Fri, 21 Jun 2019 01:13:08 GMT

Maybe there just needs to be an option to hide vertices. Segmentation in 2D drawings is a horrible block of lines....

Ling.

Re: Ellipse cannot keep its shape, but turns into a circle

Erwin Edel — Fri, 21 Jun 2019 08:18:04 GMT

Or just a 3D resolution option that is present in most of the better scripted 3D objects. I find myself setting a lot of objects to 64 resolution when I need a nice 3D presentation.

Give it a default setting for complex profile walls and beams and for curved shells that is the same as it is now, but the option to change it if you want a smoother curve (for better presentation) or lower polycount if you have a very large model.

Re: Ellipse cannot keep its shape, but turns into a circle

Lingwisyer — Fri, 21 Jun 2019 09:13:02 GMT

Having said 3D resolution being linked to a global would be nice. Overwrite elements to be simple, normal or detailed. Global 3d view quality.

Re: Ellipse cannot keep its shape, but turns into a circle

Erwin Edel — Fri, 21 Jun 2019 11:39:09 GMT

A lot of objects have this option as well, but the step in detail from 'simple' to 'detailed' I find fairly large. I tend to have 'detailed' for just normal projects and then 'more detailed' for projects where interior renders are needed which is where I start dialing up the resolution in most objects.

I could see me using simple on very large projects, but about 70% of our work is large residential single homes, so not a whole lot of objects to worry about, but generally we do want to be able to have nice presentation.

The Polycount addon (from goodies) has some option for setting level of detail too.

But yeah, basically if we could have the same options that we have for library parts for the other 3D tools, it would help