Sloping curving sweeping parapet

[Anonymous]

Trying to get a parapet which runs down a slope, sweeps around a radius then continues horizontally, to look even close to smooth.

I have tried using SEO with a curved ramp as the operator but this is leaving two 'prongs" at the ends of the ramp (and the ramp does reach the end of the curved section of wall). You can see these remnants are within the extent of the ramp in the attached image. Also the "prongs" surfaces are taking on the properties of the ramp material, even though the SEO setting is to use own properties.

I'm not that concerned with the transition of the slope not being as smooth as in real life, just want to get a close approximation.

Any ideas please? (apart from ArchiForma etc).

Thanks

[Dwight]

This is my quick method for smooth, arcing level transitions in parapets and undulating tops:

1: Draw the curved wall with a fill
2: Explode the curved wall
3: Magic Wand the fill with another fill. Setting:
- linear segments
- to the arc resolution you need for smoothness - 16-ish
4: Magic Wand the segmented fill with a mesh
-set mesh side depth to the lower of the wall heights
5: In the 3D view, elevate/adjust the mesh nodes to taste. This lets you tune the transitions.

[Richard Morrison]

This is a perfect job for the Cadimage 3D Profiler. I know you don't want to hear that, but $99 (US) will get the job done in a far more cost effective way than other workarounds.

[__archiben]

Richard wrote:
This is a perfect job for the Cadimage 3D Profiler. I know you don't want to hear that, but $99 (US) will get the job done in a far more cost effective way than other workarounds.

stuart, you should actually have the cadimage profiler as a part of new zealand's 'archicad select' membership . . .

~/archiben

[Anonymous]

Both excellent suggestions, thank you, gents. Yes, we got 3D profiler with our AC package (even before we joined the Select subscription) so no drama with the price.

Still strange about those "sticky-up-bits". Oh well.

Off I go......

[Anonymous]

S t u a r t,
Are you using the ramp object from the concrete structures folder ?
Those "sticky-up-bits" seem to be caused by the fact that the
code for that object makes the ramp with little pieces of ramp
hooked together. The first and last little pieces are hollow surfaces
and thus can't participate in an SEO as an operator.
If you make the start point of the ramp somewhat before
the element you want to cut and the end point somewhat beyond
the the element you want to cut by making the ramp's included angle
say 120° then the cutting portion of the ramp will cut
all of the object you want to cut.

The puzzle for me is why any part of the ramp object can cut
anything because the GDL command it uses is the RULED command
which is not a solid but a surface. To my knowledge only solid elements
can be operators in SEO.
Peter Devlin

[Anonymous]

Yep, you're on the right track I think, Peter. The problem with making the ramp longer than it needed to be was you need to input the overall height of the ramp, and calculating the right proportion for an oversized ramp was beyond me, with some odd angles and heights involved.
I ended up using Dwight's suggestion with a mesh, juggled the z-values as necessary, and got a reasonable result. Will probably not even view it as close as the attached image for this exercise. Just lucky there's no windows in the curved section of the walls.

[Anonymous]

S t u a r t,
Yes, the mesh tool does a lot of things.
Personally, I am addicted to the mesh tool and am always
trying to use it to model unusual shapes.
As you point out, the mesh tool doesn't do windows, so it is
indeed lucky you did not have any windows in your curved walls.

I have needed a way to cut a sloped top surface in curved walls and wanted
a ramp type object to do this because the ramp object in the library
is a hollow surface.
I made an object to do the job using the BPRISM_ command as
this command is a solid. If you are interested I can send you
this "wall cutter" which does the job accurately and is easy to set up.
Peter Devlin

[Anonymous]

Peter

Sounds good, thanks. I will PM you with my details.

Cheers