3D Selector for model parts

[tomcrane]

3D Selector for model parts

[tomcrane]

Suggest that this issue should be split - the original issue likely deferred, and a new issue created for targeting specific 3D regions of a scene.

[JulieWinchester]

Personally, I think it is likely that this is impractical for many viewer implementers to achieve on a geometry level (e.g., creating a crop or subset of geometry based on a 3D polygon selector).

At the Basel working meeting on October 26 2023, there was general support for either considering selecting parts of models to be out of scope or at least to put this on the back-burner until 3D spec work has progressed significantly further.

However, this style of selector will probably still be very important for allowing text label annotations to target a 3D polygonal region, even if it is not used for selecting parts of 3D models to annotate into a Scene.

[tomcrane]

Split into #2269, propose defer this original issue for now.

[azaroth42]

+1 to defer