Determine if an element is visible in a view

[Anonymous]

I am trying to find out if there is a way to see if a specific element is in a view. Not if it is hidden or visible, but actually in the view range/crop region/etc.

I tried using CanBeHidden, wondering if that would return false if it wasn't in the view, but even if I can't see it, it still returns true if it CAN be hidden, which makes sense.

Any way to do this? Working in 2014.

[ollikat]

Hi

I'm not sure whether there is an easy and short solution for this. But at least you could...

- Fetch and store all elements/element ids of certain view to some list/dictionary. You can use FilteredElementCollector.OwnedByView to achieve this.
- Then you can check whether certain element can be found from the list/dictionary. This tells you whether the element belongs to view.

[Anonymous]

Thanks. This definitely got me on the right path. Using FilteredElementCollector.OwnedByView was a little too granular. The OwnedByView gave me elements that were exclusive for that view (Sun Path and things like that) but I was able to dial back to just the FiltereElementCollector and give it the arguments of view and that gave me the collection of all the elements in that view. Thanks!

[arnostlobel]

Unfortunately, it is not as simple. I have just talked to the developer who is in charge of this, and I was told that it I actually not always possible to simply inquire whether an element is actually visible in a view or not. He recommends the programmer asks for the element’s Geometry with the view given in the method’s options. That may work for most of cases.

Another option, from my experience, would be to utilize a very simple export context for a CustomExporter. The context would not do anything except it would monitor which elements are coming into the context. Only elements currently and actually visible in the exported view will be sent there. In a sense, such a context would act like an element iterator.

Arnošt Löbel

Sr. Principal Engineer

Autodesk, Revit R&D

[boostyourbim]

Hi Arnost,

CustomExporters can only be used with 3D views, right? So how would you recommend determining if an element is visible in a 2D view if get_Geometry does not provide the desired results?

Thanks

Harry

[Anonymous]

How many has used the overload of FilteredElementCollector where you specify the viewid?

I've tested it now and I must say it looks like it work. I allways thought that it was only for elements owned by the view.

Any known drawbacks with using this method?

[dnenov]

Hi erikeriksson5686,

Have you tested it with linked document and active view? I'm getting an error:

It works with the document object, same code, same view id. So the error is misleading in that sense. 

Any feedback will be appreciated.

[matthew_taylor]

I can confirm this appears to work also.