Derived SketchLine3D with ReferencedEntity = Nothing

[Anonymous]

I have a part AAA with a single Sketch3D with several 3d lines in it. Each line has some attributes. Then I create a new part BBB deriving Sketch3D geometry from part AAA.

Derived SketchLine3D objects in part BBB are available in the collection oCompDef.ReferenceComponents.DerivedPartComponents.Item(1).Sketches3D.item(1). SketchLines3D

Each 3D line in this collection has the following properties:
• ReferenceComponent (non-empty, points to the part AAA)
• Reference = True
• ReferencedEntity = Nothing (!!!)

I get empty ReferencedEntity property for ANY derived SketchLine3D in part BBB so I can’t get reference to its parent line in part AAA and have no access to parent’s attributes. The same problem is with Point3D objects. I’ve stuck in these lost links.

It looks like API bug because in the same situation derived 2D sketch lines has non-empty ReferencedEntity property which always can be used to access referenced objects and all their properties.

Is there any method to get source 3d lines attributes?
I use Inventor 2009.

Thanks in advance for any idea.
ALink

[Anonymous]

I was able to reproduce this issue. I've filed a
high priority change request to address this but can't comment on when it will
be available. Unfortunately, there isn't a reliable workaround. You could do a
geometry comparison to find the equivalent entities, but you'll need to account
for transformations such a transation, scaling, etc.

Thanks for reporting this.

Sanjay-

[Anonymous]

Sanjay,
Thank you for quick response.

Luckily geometric comparison is allowable in my skeleton workflow (neither translations, nor scaling, etc.). So I have already implemented this workaround using Dictionary(Of String, SketchLine3D) object with the unique string ID’s.

In general case absent links mentioned above lead to great problems and strong limitations in using Sketch3D objects in automation of multilevel derivation in Inventor. It’s a pity because my skeletons are very often 3D. So I agree with you in high priority of this issue.


One more question:

SketchLine3D object has an AssociativeID property which “identifies this entity and is used to maintain associativity with downstream constructions” (citation from help). I’ve found that derived and source SketchLine3D objects have different values AssociativeID, so I refused to deal with them.

Will you please post some sample code to illustrate usefulness of AssociativeID property?

Thanks in advance.

ALink

[Anonymous]

The AssociativeID property was added for a very
specific internal usage and not meant for general use (which is why it is
hidden, and hence unsupported).

Sanjay-