Combine Feature not returned

[j.han97]

Hi all,

I have noticed something weird (to me) with the API. While using Combine feature to cut bodies, there is nothing returned. I.e.,

combineFeature = combineFeatures.add(combineFeatureInput)

The combineFeature is null in this case.

I went to read the documentations, and it explicitly stated that "This function returns nothing in the case where the feature is non-parametric". What is the reason of this behavior? I have used some other Features as well (PatchFeatures, etc) and there is no such issue.

I actually expected to obtain the bodies after the cut, and if combineFeature was not returned, how should I determine which bodies are resulted from this operation? 

[BrianEkins]

Notice that when you create a Combine feature when Fusion is in direct modeling mode that there isn't a combine feature shown in the browser. As a result, there's nothing to return.  Even in cases when there is a feature in the browser, they're "fake" features in that they don't remember all of the information that was used to create it. Instead, they act as a way of grouping the faces that were created by that feature.

In your case, I think you can probably get what you need by getting the bodies before and after and can assume all the new bodies were created by the Combine feature.

[j.han97]

Hi @BrianEkins ,

Thanks for your advice. Considering the potential number of bodies, I was worried about the impact on performance if I compare the bodies before and after. Currently I just switch to parametric modelling temporarily and perform the cut action, collect the resulting bodies in a list and switch back to direct modelling.

I noticed that switching the modelling environment did produce some lag as well, so I will compare these two methods before actual decision.

Alternatively, if NewComponentFeatureOperation is selected for CombineFeatureInput, is it possible to specify/obtain the new component created? This way the resulting bodies have to be in the new component, which makes it easier to get them.

[BrianEkins · Accepted solution]

I think you should be able to count on getting the last occurrence in the occurrences collection and then getting the component from it. I would use the Occurrences.asArray method since that is guaranteed to return the occurrences in the same order as they appear in the browser. I didn't test it, so hopefully that all works when in direct modeling mode.

[j.han97]

Thanks @BrianEkins , this might be the easiest approach under such conditions. I have done a simple test (under static list) and it worked well. Might need to further test it during dynamic changes (add/remove occurrences, etc).