topic Re: AC 28 Skylight Roof cut fill default can't be changed in Libraries & objects

AC 28 Skylight Roof cut fill default can't be changed

Brad Elliott — Tue, 01 Apr 2025 19:08:04 GMT

I have a project that has been brought up from AC 26. I have added a skylight to the roof and am getting a brick pattern in the roof cut. I have tried various materials as well a basic and composite structures but still have the same pattern.

If I turn the lining off it shows up clearly in he 3d model which I have attached. I tried turning the lining on as a work around and it covers in the 3d view but the brick pattern still shows up in sections and elevations.

How do I change or hide this pattern?

Operating system used: Mac Apple Silicon 12 Monterey

Re: AC 28 Skylight Roof cut fill default can't be changed

Laszlo Nagy — Wed, 02 Apr 2025 07:24:09 GMT

What is the exact name of the Library Part you are using?

Re: AC 28 Skylight Roof cut fill default can't be changed

Brad Elliott — Wed, 02 Apr 2025 19:46:58 GMT

It's Skylight Flat Panel 27

Re: AC 28 Skylight Roof cut fill default can't be changed

Barry Kelly — Thu, 03 Apr 2025 00:57:39 GMT

Looks to me like that brickwork is your roof?

You have a zero height curb in the object so the curb material will have no effect.

Looks like you have also turned off the lining.

So you are seeing the edge of your roof and need to change the edge material of the roof.

Barry.

Re: AC 28 Skylight Roof cut fill default can't be changed

Brad Elliott — Thu, 03 Apr 2025 17:57:05 GMT

Barry,

Yes, I had the lining turned off in the 3d image to show that it was overriding the steel material. I have attached two more images.

The one shows the lining turned on and covering the brick veneer. The second shows the brick veneer showing through the lining with the Elevation tool.

I'm starting to wonder if anyone else has ever used this library part? When I open a fresh AC28 template with the weird 28/27 library it is clear that the part is overriding surface of the cut roof. I'm just not able to figure out what it is. Using the attribute manager the surfaces and materials have the same id's in the two projects.

Re: AC 28 Skylight Roof cut fill default can't be changed

Barry Kelly — Fri, 04 Apr 2025 01:33:40 GMT

Can you show the expanded view of your roof surfaces?

I am guessing that the edges might be set to brick?

With no curbing and no trim, the skylight has no effect on the roof edge (for me at least).

That is all controlled in the roof settings.

Barry.

Re: AC 28 Skylight Roof cut fill default can't be changed

Brad Elliott — Fri, 04 Apr 2025 16:19:21 GMT

Thanks Barry,

That was so close and got me to the answer when I went to show you why it didn't work. I'll give the answer here in case someone else ever has this problem. Also, I'm not sure why your part seems to be acting correctly.

In classic ArchiCAD fashion it is a turned off setting that is for a surface displayed wrong.

If you look at my previous uploads the surfaces were By Building Materials because I don't like to use overrides. When this came up as brick the first thing I tried was the override shown by Barry but it didn't work. I have attached a new screen shot showing that as the condition.

When I went to show that the Surface Override shown doesn't work I clicked link surfaces for no reason and the surface changed. It was the unclicked GENERAL setting on the bottom surface that has the brick.

With By Building Materials turned on the unselected bottom surface modifies the edge material only and does not affect the bottom surface. With Surface Override on the bottom surface affects the bottom and skylight cut but not the outer surface. See the attached screen shots.

And finally, It appears in the course of bringing this file through at least 2 ArchiCAD generations that the GENERAL surface no longer has fill attached and selected the brick as the #1 surface. However, when I go to the surfaces window GENERAL does not exist? It is also not in the attribute manager. Where would I find it?

Re: AC 28 Skylight Roof cut fill default can't be changed

Laszlo Nagy — Sat, 05 Apr 2025 09:31:45 GMT

Brad,

What I don't understand in this whole thing is this:

When you override the Roof Bottom Surface (the Brick), it is not the Bottom Surface of the Roof that gets overridden; it is the side Surface of the Roof Hole (also considered an Edge). Is that correct? That light pink Edge Override color should override the sides (it does correctly) and the sides of the Roof Hole (it does not do that).

Could you show me a screenshot of just the Roof element, the whole Roof, and how the overrides affect all its various surfaces?

Re: AC 28 Skylight Roof cut fill default can't be changed

Brad Elliott — Sun, 06 Apr 2025 18:14:25 GMT

I don't particularly understand it either but it is tied to the GENERAL surface that I am unable to find or modify. It still isn't completely correct because if I select a different bottom surface it still wraps inside the skylight cut but at least it shows what it is. If I delete the skylight it all shows correctly.

Re: AC 28 Skylight Roof cut fill default can't be changed

Laszlo Nagy — Sun, 06 Apr 2025 18:14:49 GMT

That behavior looks like a bug to me, so I will report it to GS HQ.

Re: AC 28 Skylight Roof cut fill default can't be changed

Barry Kelly — Mon, 07 Apr 2025 01:43:27 GMT

'General' surface is a default surface with index number 0 (zero).

As far as I know you can not edit is at all, it is just there as default.

It seems to use a solid fill with the uncut pen colour as the hatch pen colour, or it could be an empty fill with that pen as the background.

It has not texture, so I am not sure why you are seeing brick.

When I open my template in 28 I see something I have not noticed before.

The fill is a question mark, but is still works as it did in previous versions.

It is the same in the default Graphisoft template (AUS version) so I am assuming that it is deliberately like that.

Barry.