Home
Reply
Regular Contributor
Posts: 55

Operations fail for a mixed body

Hello,

I have a problem with some operations after I attached a wire to a body (solid or sheet). Namely, api_stitch throws ACCESS VIOLATION and projection stop working. Is it a known limitation?

 

I checked a couple reference: on one hand 

 

https://doc.spatial.com/get_doc_page/articles/m/a/n/Manifold_and_Non-manifold_Objects_2264.html 

 

says that most operations support NM regions (and I believe an attached wire goes into this category). On the other hand,

 

https://doc.spatial.com/get_doc_page/qref/ACIS/html/group__STITCHAPI.html#ga60be6f7d7efb636fe1d56b77...

 

says "Stitching provides a way to connect unconnected faces to make sheet or solid bodies that are topologically complete", and it looks like a hint that mixed body are not supported.

Regular Contributor
Posts: 55
0

Re: Operations fail for a mixed body

Projection also fails:

 

api_project_wire_to_body failed:
Error number 60000
Error message: operation unsuccessful
Error identity: API_FAILED

Spatial Employee
Posts: 151
0

Re: Operations fail for a mixed body

Hi yt I think stitching is primarily intended for sheet bodies and solids. I haven't heard of anyone stitching a wire to a sheet before. The failure of project wire is probably something worth logging an incident for. If I may ask, what is it that you are trying to do and how does the API failure cause a problem for you? Eric
Regular Contributor
Posts: 55
0

Re: Operations fail for a mixed body

Perhaps there is a misunderstanding: I'm not stitching a wire to a sheet. I created a mixed body with:

   api_boolean( pWireBody, pBaseBody, NONREG_UNION );

 

After that, I try to perform api_stitch for the resulting body. It fails with segm. violation in function  hh_are_connected_vertices_positionally_same() called under api_stitch (I have a stack).

 

The problem is obvious: After I attached the wire to the body (no insanities, perfect result), the resulting body seems to be unusable since I can't perform many operations on it.

 

 

Regular Contributor
Posts: 55
0

Re: Operations fail for a mixed body

Addition to make my intention clear: I'm trying to topologically attach a wire to an existing sheet/solid body.

Spatial Employee
Posts: 151
0

Re: Operations fail for a mixed body

Hi yt

 

Thanks for the clarification.  I guess I was asking what you are trying to model by having a solid/sheet with a wire dangling from it.  If you can describe what is going on at a high level maybe there is another way to do it.

 

The ACIS data representations do support this.  However, historically it is not a case that many API authors were expecting.  ACIS operations tend to be tested on initial (unit) test cases and whatever regression cases customers submit.  Customer support can triage unexpected behavior and classify it as a bug or enhancement request.  

 

I hope this helps

 

Eric

Highlighted
Regular Contributor
Posts: 55
0

Re: Operations fail for a mixed body

Thanks Eric!

The intention is to create a set of desirable wires and then to cover/skin them. So basically we want to have a flexibility to close any holes using wires with consequent operations. In most cases we'll not have dangling wires as a result.

We are able to implement the workflow above even with wires which are not topologically attached to the base body. But topol. attachment makes things easier, for example chain selection is simpler then topological connectivity is present.