Particles overview
Snow, embers, sparkles, fireworks — particle effects in Chapter Vision are presets that live inside your chapter and play back identically on every device.
Presets travel with the chapter
A particle effect is a preset: a complete recipe covering emission, physics, color, look, force fields, and optional secondary spawning. Every knob is described in the particle parameter reference. Presets are part of the chapter document itself, so they save with the bundle, sync live between Chapter Studio and Chapter Vision, and play back in the player without any separate export.
You don't have to start from a blank slate. A built-in catalog of presets ships with both apps; pick one that's close, then tweak it into your own in the preset editor.
Attached or standalone
An emitter can live in two ways:
- Attached to an entity. The emitter rides its entity: move the entity, and the effect moves with it. Perfect for a smoldering torch, a sparkling crown, or engine exhaust.
- Standalone. Add a free-floating emitter from the add menu, position it like any other entity, and it becomes a scene element of its own, like a snowfall region or a wall of rising embers.
Note. On Vision Pro, a standalone emitter has no mesh to grab, so the editor gives it a small pick-proxy sphere. Look at the little sphere to select the emitter, then move it with the gizmo like anything else. The proxy is editor-only; your audience never sees it.
Burst vs. loop
Every preset is either looping or one-shot, and the difference decides how it behaves in your segment:
| Mode | Behavior | Use it for |
|---|---|---|
| Loop | Emits continuously for as long as its entity is visible. | Ambience: falling snow, drifting embers, dust motes, steam. |
| Burst | Fires a single burst of particles at the moment its entity is revealed, then goes quiet. | Punctuation: reveals, impacts, confetti pops, fireworks. |
Because a burst triggers on reveal, timing one is just timing a reveal: place the reveal where you want the pop, and the particles arrive on cue. You can also fire particles as an explicit timeline event with the Add Particle action (see the actions reference), which is handy when you want several bursts from the same emitter across a segment.
The preset editor, live
Open a preset and every parameter sits alongside a live preview. The preview updates in place: existing particles keep flying while new ones adopt your changes, so the simulation never restarts under you. Drag the birth-rate slider and watch the density shift mid-fall; nudge a color and see new particles blend in among the old. That continuity matters most when tuning slow, ambient effects. A snowfall that reset on every tweak would be impossible to judge.
One-shot effects get their own control: the Burst Preview button replays the burst from the top, so you can watch your firework explode as many times as it takes to get the shape right.
Tip. Tune ambience with the live preview and let it run, judging loops over at least one full particle lifetime. Tune bursts with repeated Burst Previews, changing one parameter between presses.
Secondary spawned emitters
A preset can carry a second, child emitter that spawns from the particles of the first: on each particle's birth, death, or continuously along its flight. This is how layered effects are built: a firework whose shell streaks upward and then crackles, a comet that sheds glitter along its path, raindrops that splash where they die. The child emitter has its own full parameter set, and can inherit its parent's color and a share of its velocity so the layers read as one effect. Details live in the parameter reference.
Where to go next
- Particle parameter reference: every parameter, grouped and explained, with recipes.
- Actions reference: the Add Particle action and its timeline behavior.
- Animation overview: animate the emitter's entity and the whole effect travels with it.