What a model is made of, hiding parts per type, and switches your visitors can flip.
A part is one named piece of a type — a worktop, a plinth, a length of trunking. The Parts card on the model page lists what the type on screen is made of, with a Hide/Show switch beside each.
How finely a model divides into parts is decided by the family author, not by VUE.
Both readings are live and will be for a while — nothing re-converts until you re-upload — and one model can contain both. The card tells you which one you are looking at.
The practical consequence is worth stating plainly: three anonymous panels sharing one subcategory are one part, and there is no way to split them inside VUE. If you need them separate, they need separating in Revit. Each row says how many pieces it covers, so you can see the blast radius before you switch anything off.
A model made by combining others keeps each piece's parts separate, so switching off the enclosure's frame leaves the tray's alone.
Each material within a piece is its own part, even where its author drew several of them as a single object — so the enclosure's chrome and the tray's chrome are separate rows even when they share a name.
What still spans the pieces is hiding by material name rather than by the row, because that has always meant everything in this type made of this material.
Switching a part off hides it on that type only. A 40-type family means doing it 40 times; there is no "hide everywhere". That is deliberate — "hide the worktop on the 1200mm unit, keep it on the 900" is the case this exists for.
The setting is stored against the part's name rather than against the converted output, so renaming a material, renaming a type, or overriding a variation are all safe.
Whether it survives a new upload depends on how you upload. Republishing the same family from the Revit plugin replaces the existing model in place and keeps everything you have set. Uploading a file through the studio creates a new model with a new address — your hidden parts, visitor options, renamed axes and material overrides stay with the old one. See replacing a model later.
Renaming a subcategory in Revit is not. The stored name no longer matches anything, so the part comes back into view — on your live embeds, without warning. If you rename one, check the model afterwards.
Two more things worth knowing:
The Parts card is collapsed by default and shows a count when anything is hidden. A hidden part cannot be clicked in the model, so the card is the only way back.
Some models have no Parts card at all. That means nothing in the type has a name to store — usually a mesh export whose materials were left unnamed.
The Inspect button sits beside the pop-out above the model. Turn it on and the viewer takes a blue border; click anything and VUE tells you what it is.
Selecting a part highlights every piece that shares its name, which is the honest preview of what hiding it would do. The name appears under the triangle count. Right-click for the detail: its stable id, triangle and vertex counts, how many pieces it covers, its material, and a Copy details button. The right-click menu also offers Hide in this type, which does the same thing as the switch in the Parts card.
Dragging still orbits the model — only a click selects — so Inspect does not take the viewer away from you.
Inspect is a studio tool. Nothing about it ships to your embed, and visitors cannot click parts of your model.
One caution on the identifiers it shows: the id is stable and survives a re-upload. The uuid is generated fresh every time the model loads and identifies that object in that session only. It is labelled as such in the panel. Do not build anything against it.
A visitor option is a switch you offer the visitor, in the embed, that shows or hides parts of the model: with or without the power module, with or without the lid. One model, optional parts, no extra Revit types.
This is the opposite of hiding a part. Hiding decides what a type is; a visitor option leaves the choice open.
Set them up in the Visitor options card below Parts:
Options are per family, not per type: you author "Power module" once and it applies to every type that has those parts. Each row tells you how many of your types it will actually affect, which matters more than it sounds — on a pre-0.6.0 model a part is a material, and "everything made of chrome" may be a handrail on one type and a plinth on another. Check the number before you save.
An option that names a part a particular type does not have simply does nothing on that type. That is normal — the small size of a range has no power module — rather than an error.
A visitor option can only hide more. It can never reveal a part you switched off in the Parts card, whatever the visitor does and whatever is in the link. So anything you hide stays hidden, and the options are strictly a choice among what is left.
Switching type keeps the visitor's choices, and flipping an option leaves the type alone — they are separate controls that do not fight each other.
One current limitation: an option that starts off is not reflected in the still image shown before the model loads, so that image will show the parts until the visitor presses play. If that matters, leave the option starting on.
Separately from all of this, a parameter you define as Yes / No now renders as a switch in the embed rather than a two-item dropdown. That kind of parameter still selects a type — the type whose value matches — so it behaves like Size or Finish, not like a visitor option.
The two look alike because both are switches. The difference is what they do: a Yes/No parameter picks a different product, and can grey out when that combination does not exist; a visitor option only shows or hides parts of the product you are already looking at.
When you define one, fill the column in for every type and variation. A blank cell is not "No" — it is unset, and a parameter that is missing anywhere becomes no control at all. The grid warns you before you save. See types and the configurator.