UI in 3D viewport n-panel vs Object Properties

[PardhavMaradani]

Hi @BradyAJohnston , @yuxuanzhuang , I'm starting this to discuss about the location of the UI elements that we talked about in the last meeting.

After playing with this a bit, I am of the opinion that whatever we added as part of GSoC 2025 should reside in the 3D viewport n-panel. If any, I would recommend moving the rest of the stuff (which is mainly only the Import part - see later about the contents in the Object and Session tab currently) as a separate panel here in the future. I will outline my reasons for this:

• First, Blender UX. Anything that is directly tied to immediate viewport changes reside in either the n-panel (called properties shelf or sidebar or viewport display panel - accessible by n key) or the tool shelf (accessible by t key). This is also why most of the add-on UI interfaces reside here as opposed to the Object Properties, which is for data and other long term settings
• Object Properties is not accessible when we maximize the 3D viewport region (Ctrl + Space), where as n-panel is
• A new window (Window > New Window) for 3D viewport behaves the same as above and Object Properties is not accessible (unless it is a New Main Window)
• Any of our UI within the Object Properties has to be part of a single panel - i.e., we cannot have multiple independent panels grouped together like we have in the 3D viewport n-panel. This single panel can have sub panels (collapsible - like how we have within styles / annotations in the n-panel), but then all of the code will have to be one giant panel. We cannot have a new tab (with its own icon etc) in the Properties editor because bl_context has to be set to one of the supported values. The other alternative is to have separate tab buttons like how we have in the current MN UI in Scene properties, but this is not that usable and scalable
• The Region Overlap setting in Preferences > Interface > Editors allows whether the n-panel is showed as an overlay or separate region, which is a user preference
• Using the n-panel would keep it consistent if we are to later add MN specific config/settings in other places like the Geometry Node Editor or Compositor (region specific)
• With the current MN template setup, the Object Properties (right pane) is quite wide and the region is divided between the 3D viewport and Geometry Node Editor - which I agree makes the actual content area in 3D viewport smaller when the n-panel is open - but that is an independent layout issue (that is also user customizable) and I guess should not be the driving factor for this change
• About the current UI in Scene Properties, the Session tab is already something that you indicated can be removed (I don't know about the impact of the Create Object buttons there). In the Object tab, there is configuration only for the Trajectory entities (regular and OxDNA) - frame averaging, subframes, offset and selection attributes. The rest like Molecule, Ensemble and Density seem to have no additional configuration

I will add any other details as I come across them, but above are some high level thoughts. Thanks