topic Re: Curving Roof Pivot Line in Modeling

Curving Roof Pivot Line

Anonymous — Tue, 23 May 2023 13:07:48 GMT

Hi,

I am modelling a building with a curved exterior walls and need to put a mono pitched roof on. Ideally I would like to curve the roof pivot line to the curved exterior wall but don't think archicad will allow this. Is there a way of creating a similar effect?

Thanks

Re: Curving Roof Pivot Line

Dwight — Mon, 20 Oct 2008 15:23:23 GMT

What roof direction?

Re: Curving Roof Pivot Line

Anonymous — Mon, 20 Oct 2008 15:33:30 GMT

Dwight, I've uploaded a new jpg that will hopefully illustrate my query more clear. Thanks....

Re: Curving Roof Pivot Line

Dwight — Mon, 20 Oct 2008 16:47:30 GMT

You'll array an arced series of narrow roof wedges to solve this one.

five segments illustrated

Re: Curving Roof Pivot Line

Karl Ottenstein — Mon, 20 Oct 2008 16:58:12 GMT

As Dwight points out, to model it with the roof tool, you need to create segments with a linear pivot line and then multiply them. In life, you will probably have beams and roofing between them, and so this will mimic the actual construction.

If you need a completely smooth curved roof, you can (?) model it with the wall tool using a complex profile. The profile would be a cross section of the roof, and then use the curved wall geometry to draw the surface.

Cheers,
Karl

Re: Curving Roof Pivot Line

Anonymous — Mon, 20 Oct 2008 17:11:29 GMT

I am surprised that Dwight did not suggest the complex profiled wall
method since he is the complex profiled wall evangelist.

Alternatively, the method suggested in this post might work.
http://archicad-talk.graphisoft.com/viewtopic.php?t=10681
Peter Devlin

Re: Curving Roof Pivot Line

Dwight — Mon, 20 Oct 2008 17:35:23 GMT

I'm embarrassed. It was the pivot line talk that thru me off.

Re: Curving Roof Pivot Line

Karl Ottenstein — Mon, 20 Oct 2008 17:51:06 GMT

I wouldn't be beat yourself up over it. If this is a roof that will be built, then a smoothly curved surface is highly unlikely - and so sections through the building would more accurately reflect construction with Dwight's original / traditional segmented proposal.

Besides, even the complex profiled wall thing falls apart if the offset of the two curved walls differs, or if one wants the result to behave like a real roof - capable of supporting skylights, or roof accessories such as standing seam metal.

We don't really know what the end goal of the original poster is...

Cheers,
Karl

Re: Curving Roof Pivot Line

Anonymous — Tue, 21 Oct 2008 00:31:11 GMT

What about modelling the required roof form with the mesh tool and then using the mesh-to-roof function?
As Karl has indicated, the type of construction proposed will determine the specific form - any type of framed and clad roof will be segmented to suit the profile of the sheeting.

Re: Curving Roof Pivot Line

Dwight — Tue, 21 Oct 2008 00:41:39 GMT

The mesh tool will take longer and accuracy will be difficult.

Archicad's tools work so well for conventional structures because they constrain/extrude well.

Re: Curving Roof Pivot Line

Anonymous — Tue, 21 Oct 2008 07:39:18 GMT

Thanks for all your help I shall try the segment approach...

Re: Curving Roof Pivot Line

Anonymous — Tue, 21 Oct 2008 12:08:43 GMT

Dwight, your suggestion worked thanks.

Now for another problem. I now want the roof line to slope (please see illustration). Has anyone got any ideas how I can do this?

Re: Curving Roof Pivot Line

Anonymous — Tue, 21 Oct 2008 12:23:07 GMT

Can you trim to mesh or do you have to use the Solid Element Options?

Re: Curving Roof Pivot Line

Dwight — Tue, 21 Oct 2008 12:37:24 GMT

You can get into a hellish attempt to rotate the pivot line a little to tilt the roof parts, multiply/rotate and then elevate each part in sequence.

You can.

But now you need to look at other ways to do this.

You might look at a four node mesh if it doesn't need to be accurate [or have thickness] - then convert to roof using "Create Roofs From Mesh" tool as found by downloading the "Goodie" from Graphisoft's website - look under "Archicad "HELP" for goodies link. Altho my test didn't work so well.

Re: Curving Roof Pivot Line

Dwight — Tue, 21 Oct 2008 12:46:28 GMT

novice wrote:
Can you trim to mesh or do you have to use the Solid Element Options?

I have not found a "Trim to iMesh" command.

Re: Curving Roof Pivot Line

Anonymous — Tue, 21 Oct 2008 13:01:06 GMT

Thanks again Dwight, I've already downloaded the Create Roof from Mesh tool, I shall give it a go now

Re: Curving Roof Pivot Line

Dwight — Tue, 21 Oct 2008 13:06:06 GMT

BTW: "iMesh" is only on Mac.

Re: Curving Roof Pivot Line

Anonymous — Tue, 21 Oct 2008 13:16:01 GMT

Cheers Dwight, it has worked

Re: Curving Roof Pivot Line

Dwight — Tue, 21 Oct 2008 13:21:58 GMT

always post results

Re: Curving Roof Pivot Line

Ralph Wessel — Tue, 21 Oct 2008 22:08:12 GMT

novice wrote:
Now for another problem. I now want the roof line to slope (please see illustration). Has anyone got any ideas how I can do this?

You can make this roof as a single object quite easily with OBJECTiVE. Referring to the attached image:

1) You can place an object which is either a uniform or custom profile where the roof is required, and use OBJECTiVE's Bend and Offset tools to shape it to the required curve and rise.
2) The finished object provides detailed control over its entire geometry including the roof width/depth, pitch, curvature, overall rise, and offsets at the ends.
3) The finished result - a single, malleable object that took only moments to place.

For more information, take a look at http://www.encina.co.uk/objective.html