Jump to content

Elliptical walls?


Recommended Posts

  • Replies 111
  • Created
  • Last Reply

Top Posters In This Topic

Elliptical in plan.....curved walls work to a certain degree however as soon as you have to adjust the space there's quite a lot of moving and joining to do...preferably you would just want to adjust the ellipse axes.....it's strange i seem to remember boast and showing my collegues the it is possible in VW (in an earlier version) and not in ArchiCAD?!

Is it possible to draw and elliptical polygon? I've tried but not succeeded, otherwise i could use the create walls from polygon command.

Link to comment
  • 4 months later...

hello, I work with VW for a week or so now. I use the German Vector Works 2009 student edition:

I've createt an Elliptical wall with the "create wall" command, and now I have a Problem:

Because the "generated" wall consists of several smaller wall-pieces - I'm unable to insert doors an other symbols correctly.

Does anyone have an Idea how to "join" the wall-pieces to one large wall?

here is a picture of the Situaton:

http://www.vectorworksforum.de/download/file.php?id=629

Sorry for my bad english - I'm not a native speaker, but I hope you can help me solving the problem.

greetings

Markus

Link to comment
  • Vectorworks, Inc Employee

The most scholarly and complete discussion of ovals, ellipses and comparable shapes that I've found is P.L. Rosin's discussion "On Serlio's Construction of Ovals" a brief summary of which can be found at:

http://users.cs.cf.ac.uk/Paul.Rosin/serlio.html

(A link to the more complete paper is at the bottom of the web page.)

Vectorworks' Oval tool generates an ellipse construction. The best way to draw elliptical wall layouts would be to use Serlio's "Construction I" as shown in Rosin's paper. This is the dual-arc-radius method, and should yield the minimum number of tangents (which of course prevent object insertions.)

HTH.

Link to comment

How do you know it's an ellipse?

If I draw a true ellipse first then the oval tool seems to be able to replicate it using the second mode.

But why are the foci not available?

If I remember high school (and I probably don't) every ellipse is an oval, but not every oval is an ellipse.

I'm assuming that the oval tool can draw non ellipse ovals. How would you know if you drew an ellipse?

michaelk

Link to comment

There is a hidden way to create an ellipse in VW.

There is a tool set that is not part of any default workspace, called the Solids Tool Set. It has an Ellipsoid Object Tool.

The tool creates ellipsoids as parametric objects with settings for the x axis, y axis, and z axis.

Once you have a 3D ellipsoid, it can be used as a guide to create a 2D ellipse.

michaelk

Link to comment

http://users.cs.cf.ac.uk/Paul.Rosin/serlio.html

(A link to the more complete paper is at the bottom of the web page.)

Vectorworks' Oval tool generates an ellipse construction...

Robert

Thanks for the link, that was very helpful.

Just so I understand: Every oval drawn w/ the oval tool is an ellipse?

The distinction is that the axes of VW ovals share midpoints and therefore the oval is symmetric about both axes - therefore, it is an ellipse?

And it is not possible to use the VW oval tool to draw an oval that is not symmetric about both axes? Therefore all VW ovals are ellipses?

My poor little brain always thought of ellipses as defined by conic sections or defined by foci and ovals as cleverly combined segments of circles.

This is all way off topic. I probably should have started another thread.

To bring it back to the topic, it would be nice to see the Convert > Objects From Polyline...>Walls create a continuous wall rather than many round walls.

michaelk

Link to comment

How perfectly? It was a few years ago, but the VW oval and a 2D-representation of a conic section were anything but a perfect fit. The discrepancy was significantly more pronounced when the sectioning angle became more acute.

After I posted the proof (images) to the VW Mailing List, the esteemed Robert Anderson banned me from the list.

Let's see what happens this time.

Link to comment
How perfectly? It was a few years ago, but the VW oval and a 2D-representation of a conic section were anything but a perfect fit. The discrepancy was significantly more pronounced when the sectioning angle became more acute.

Hi again Petri,

After our conversation about the subject of ovals and ellipses some time ago......

I did a quick test with a very flat oval and measured the sum of the foci to oval points in a number of places.

There was an error but it is small. About 0.05% of the expected size.

Hope you're keeping warm there at the North Pole

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...