Arch Shape2D view cyclic dependency

[brjhaverkamp]

Hello all,

I ran into something new today. Suddenly I noticed I have a cyclic redundancy in my model, due to a dependency of a Shape2Dview on some dimensions.
The dimensions are in the Section plane on which the Shape2Dview again depends. Hence a cycle.

But all my other dimensions are not linked to the shape2Dview, even though I created them the same way. (as far as I can see)
Moreover it seems only the recently added dimensions are affected. And since I upgraded to a latest 0.18 daily ubuntu package this morning before starting working on it again, it might be a bug in the latest version.

Has anyone seen the same issue?

Bert

Screenshot from 2019-03-17 16-07-08.png (349.66 KiB) Viewed 1207 times

[brjhaverkamp]

Just to follow up. I checked some older versions and the cyclic dependency started yesterday. So no link to the new version I downloaded.
Also in freecad on my windows laptop the same effect appears when I add a dimension to the Trusses groupl.

I temporarily fixed dependency problem by taking the dimension group out of the section. (no measurements for now in my drawing for now.)

But then somethig weird happened. When I added measurments to the front section, using the same method as before, 2 out of the 10 dimensions had the dependency problem. the rest was OK. I deleted these 2 and redid them. Now all of them are fine. I have no clue what I do different. But something in the way I add dimensions is triggering this..

[chrisb]

Hard to say what happened without knowing every single step of creating the model.

[brjhaverkamp]

Well, the procedure is just adding dimensions to a Shape2Dview:-)

The problem is serious enough though. Suddenly I had cyclic dependencies out of nowhere, that were ruining my model.
That shouldn't happen without some serious mis-use of tools. (It is a part-of-life in the Part design WB unfortunatey, if you are not careful.)

But I recognise what you are saying. I'll spend some time finding if I can find a pattern. I hope I can find something that triggers this.

Bert

[chrisb]

I'll spend some time finding if I can find a pattern. I hope I can find something that triggers this.

That would be great to know where it comes from. Then it might be prohibited.

[yorik]

I believe it is because you are placing your dimensions in a group which is part of the section plane.

[brjhaverkamp]

Hi Yorik,

Adding the dimensions in the section plane is the way to get them in in an Arch draw, as I understand it.
All my dimensions are grouped and then added to a section plane for this reason.

The difference for these dimensions is that there is a link between the shape2Dview and dimensions. That doesn't happen for my other dimensions.
Strangely, when delete them and re-do them, there is no link to the shape2D view. So it seems to have something to do with the way one creates them.


I haven't found a pattern yet, but I still need to try more.

[yorik]

One thing to check: Select one of the problematic dimensions, and in the python console:

Code: Select all

Gui.Selection.getSelection()[0].Support
Gui.Selection.getSelection()[0].LinkedGeometry

Normally both these properties should be empty, or at least not contain the section plane itself.
If you could attach your file here, we can have a look too

[brjhaverkamp]

Hi Yorik,

I think I am onto something. When I select a line in a Shape2D view and then the "create a dimension" button, it will create a dimension on the line and there will be a dependency. If I select the two endpoints of the line to create a dimension, there is no dependency.

This might make sense but it screws up the workflow to create a techdraw with dimensions. At least my current workflow. If there is a better way, please let me know.

The culprit file is attached/referenced here. The problem is with the "Dimensions trusses" group (and the dimensions therein and the "Shape2Dview trusses" https://www.oatfield.nl/nextcloud/index ... dXXpYinzRx

Regards,

Bert

[yorik]

Thanks for investigating further. Normally this shouldn't create a cyclic dependency... the dimension depends on a line, the section plane depends on both the line and the dimension, that should work. But I'll have a look at your file...