How to offset faces for parts in a for-loop

Jose_Morales

I have a list of faces which I'm running through a for-loop to extrude each one as a unique part, attribute part metadata, and offset (inwards) each one. When I add the opFaceOffset feature I get an error message which I can't seem to wrap my head around.


:


Below is the error message:



I have tried shifting the order between "panel_number" and the opOffsetFace feature but ran into other issues there. What am I missing? 

Any help is appreciated, and thanks in advance.

NeilCooke

Details are here (if you can decipher it): https://cad.onshape.com/FsDoc/library.html#Id

If you change how you construct your id's to something like this, it will be OK:

id + ("panel_extrude" ~ panel_number) 

lana

Or you can do id + unstableComponent(panel_number) + "panel_extrude", id + unstableComponent (panel_number) + "offset_face", etc.
Use of unstableComponent will give you downstream reference stability.

MBartlett21

You would also want to use setExternalDisambiguation(context, id + unstableIdComponent(panel_number), face) so that we have the reference for the feature.

Jose_Morales

Thanks a lot guys, I'll let you know how it goes.

@lana Is this mainly used when performing multiple dependent operations within a loop? 

@MBartlett21 Is there documentation on when to use that? I've yet to wrap my head around feature ID's, honestly

@NeilCooke Thanks for the link; *puts on helmet* I'm going in!

lana

Yes, Ids should form tree structure:
featureId.0.op1
                  .op2
                  .op3
               .1.op1 
etc.
When you create a separate set of operations per entity in a query, you have to expect that when editing feature input, number and order of entities will change. unstableIdComponent(index) tells FS that this component is not important to resulting geometry identity.
I did not mention external disambiguation in your case because it looks like panels are input to the feature and the first operation in the loop is panel extrude. This means that each iteration will be disambiguated by the panel face identity.  external disambiguation is needed is the set of operations in the loop starts with something like sketch or opPlane, which is defined only by geometry with no dependencies.

MBartlett21

lana said:

[...]
I did not mention external disambiguation in your case because it looks like panels are input to the feature and the first operation in the loop is panel extrude. This means that each iteration will be disambiguated by the panel face identity.  external disambiguation is needed is the set of operations in the loop starts with something like sketch or opPlane, which is defined only by geometry with no dependencies.

@lana
Is it mentioned about this in the documentation anywhere?
I did not know that I did not need to disambiguate if I was just operating on a face.

lana

@MBartlett21
It sort of says so in the setExternalDisambiguation documentation, but does not make it very clear. 

Used to set external disambiguation for operations with unstable component in id. The disambiguation will be applied to results of sub-operations which otherwise don't track dependency e.g. [Sketch] , [opPlane], [opPoint]

However, functionality is smart enough and if no disambiguation is necessary, there'll be no performance penalty for setting external disambiguation.