SwitchSplat

Learning Discrete Object States from Casually Captured Scenes

SIGGRAPH Asia 2026 · Conference Papers

Yizheng Xie1* Yalda Foroutan1* George Shramko1 Daniel Rebain2,3 Shrisudhan Govindarajan1,3† Andrea Tagliasacchi1,4,3†

1Simon Fraser University 2University of British Columbia 3Wayve Labs 4University of Toronto

*Equal contribution   †Equal advising

The car from the front right, rendered by SwitchSplat
Your turn.Tap a part to switch it. Drag to look around.Tap a part below.
Combination never filmed

Scene tours

Fly-throughs of the learned scenes, switching objects along the way. Tap a clip to watch it full size.

Abstract

3D Gaussian Splatting has made high-fidelity 3D reconstruction fast and accessible, yet existing representations assume a static world. This assumption breaks down in casual captures, where a user naturally interacts with the environment – opening doors, toggling switches, or moving objects – introducing discrete state changes that no current framework can model. Time-conditioned dynamic methods such as 4DGS conflate when a state was observed with what state the scene is in, limiting them to replaying seen sequences rather than composing arbitrary object configurations. We present SwitchSplat, the first 3DGS representation to address this gap via a base+slot decomposition: a shared static base captures the invariant scene, while each slot independently holds the two binary states (on/off) of one interactable object. Because the assignment of Gaussians to slots is fully differentiable, the model discovers the geometry of each state directly from video, without manual annotation. At inference, the user can freely combine slot states and render the resulting scene from any viewpoint. We validate SwitchSplat on a new casual-capture dataset and show that it outperforms static and dynamic baselines in novel-view synthesis quality, while uniquely supporting rendering of state combinations never seen during capture.

Method

One casual 360° video in. A 3D scene with an on/off switch for every part out.

1Capture: open each part once

Four parts make 16 combinations. The video shows only 5.

2Each Gaussian picks a team

Each 3D blob joins the fixed base, or one part's off or on state. A switch only shows or hides its own part, so any combination works.

Car with the right door's closed state highlighted
switch off
Both door states stored together
what the model stores
Car with the right door's open state highlighted
switch on
omega = p0 + sum over k of ( s_k p_k^on + (1 - s_k) p_k^off ) sk is the switch of part k

Watch the Gaussians pick their teams

The Car while it trains.

+ = = base door: closed part door closed door: open part door open

3The video sets the switches, then you do

A vision-language model roughly guesses when each part moves. Training sharpens the guess. No manual labels.

✓A rough guess is enough

Start roughly centred on the right moment and the window snaps into place. All 59 model guesses do.

229 different starting guesses on Kitchen 2.

Results

Sharper moving parts, and +2.1 dB PSNR over the next best.

CarDishwasherDrawersFridgeWasher
FullCircleForoutan et al.28.99 dB
DeGaussWang et al.30.30 dB
4DGSYang et al.30.55 dB
SwitchSplatours32.65 dB

PSNR averaged over all ten test scenes (paper, Table 1).

Explore the scenes

Every scene runs live in your browser (WebGPU required). In SwitchSplat scenes, flip each object's state and view any combination from any viewpoint.

SwitchSplat dataset 12 casually captured dual-fisheye scenes

FullCircle scenes 23 static reconstructions from the FullCircle dataset

FullCircle Lounge (MCMC) FullCircle Safeway 2 (MCMC) FullCircle Street 2 (MCMC) FullCircle CS (MCMC) FullCircle Lounge 2 (MCMC) FullCircle Robot (MCMC) FullCircle Safeway 1 (MCMC) FullCircle Street 1 (MCMC) FullCircle Trees (MCMC) FullCircle Bedroom 2 FullCircle Bedroom 3 (MCMC) FullCircle Dark FullCircle Flat 1 FullCircle Flat 2 FullCircle Kitchen FullCircle Lab (MCMC) FullCircle Oslo FullCircle Parking (MCMC) FullCircle Persons FullCircle Room 1 (MCMC) FullCircle Room 2 FullCircle Room 3 (MCMC) FullCircle Safeway 3 (MCMC)

FullCircle · 23 scenes

Casual 360° captures, in their own viewer on the FullCircle project page.

Open the FullCircle viewer → About FullCircle

BibTeX

@inproceedings{xie2026switchsplat,
  title     = {SwitchSplat: Learning Discrete Object States from Casually Captured Scenes},
  author    = {Xie, Yizheng and Foroutan, Yalda and Shramko, George and Rebain, Daniel
               and Govindarajan, Shrisudhan and Tagliasacchi, Andrea},
  booktitle = {SIGGRAPH Asia 2026 Conference Papers},
  year      = {2026}
}