How a published scene loads
Models in distant neighborhoods wait until a visitor is near them, and a shaped stand-in holds the space until they arrive.
Open in the interactive manual →The interactive version has full-text search, a table of contents, and light/dark themes.
A multi-page scene used to download every model on every page before a visitor saw anything, so a big site made its first visitor pay for rooms they might never walk into. Published scenes now load a neighborhood at a time: a page's models are fetched when someone is near enough to care, and a stand-in holds the space until then.
There's nothing to switch on. It happens on any published scene with more than one page node.
What counts as "near enough"
Three sets of pages always have their models in hand, and the rules are deliberately generous. Being wrong this way costs a little bandwidth, being wrong the other way means someone arrives somewhere and waits:
- The page you're standing on.
- Every page within 60 metres of it: a neighborhood you can see from here must never be a field of grey shapes.
- The immediate previous and next page in page order, however far away they are, because that's what a swipe and the pager reach.
Only models wait, and only for downloading: everything in the scene is still drawn from everywhere unless you scope it to a neighborhood, which is the separate, opt-in half of this. Lights, particles, video, and page panels behave exactly as they always did. A single-page scene defers nothing (there's nowhere to travel from), which is one good reason to split a large site into pages placed well apart. The Scene Weight window shows you the split: what a visitor downloads on arrival versus what waits for them.
The editor never defers. While you're authoring you always see the real model.
What a visitor sees while they wait
A model that hasn't arrived is drawn as a soft solid stand-in at the model's own stored size, so nothing shifts, jumps, or resizes when the real geometry lands. Two readings, both honest:
- Brighter, with a slow band of light sweeping up it: downloading right now.
- Dimmer and still: too far away to have been asked for yet. Nothing is being spent on it.
Choosing the stand-in
A stand-in at a model's bounding box is a box, which turns a deferred forest into a car park. So the shape is yours to pick, per scene, in Settings ▸ Visitor Chrome ▸ Loading placeholders:
| Option | What stands there |
|---|---|
| Auto (default) | The outline if the model has one, otherwise its thumbnail, otherwise a plain block. |
| Shape | The model's own silhouette: a tiny baked copy, a few hundred triangles and no textures at all, tens of kilobytes against the real model's megabytes. A forest reads as trees. |
| Card | The library thumbnail, stood up in the model's volume like a preview card. Nearly free, since most models already have one. |
| Volume | A plain soft block at the model's size. The plainest option, and the fallback for everything else. |
Every option except Volume falls back down that chain, so a model that's missing an outline is never a hole in your scene: it just gets the next-best stand-in. Picking Volume is absolute: it's the one to choose if you'd rather not spend the extra small request at all.
The section bar tells visitors too
On a scene using guided scroll, each dot on the section bar opens into a slowly spinning ring while that section's models are still coming, then collapses back to a dot when they land. Its label reads ", loading" as well, so the state isn't carried by animation alone, and reduced-motion visitors keep the ring without the spin.