Renderer
How it looks
Gaussian splats, Marble exports, Genie frames, SOG. Pretty, fast, often fake beyond the capture frustum.
Urth · spatial indexes · 2026-09-21
The world is not a video.
WeftOS already indexes where, similar, and why. Urth densifies the planet only where we observe.
BVH · HNSW · Graph Views · ADR-056 / 078 / 079
↓ scroll — renderer, simulator, planner
Three jobs, one overloaded name.
In 2026 “world model” names three jobs. WeftOS keeps them apart: appearance may be generated; metric shape lives in the BVH; plans ride Graph Views and optional LeWM. Generative fill is never treated as surveyed truth.
Simulator
What has shape
AABBs, collider meshes, Object vs Event leaves. This is the only column Urth treats as metric.
Planner
What to do next
Agents, fusion graphs, latent predictors. Useful priors — never the world source of truth.
Four lenses. One chain.
ECC already had HNSW, causal edges, and UNID lookup. ADR-056 added the missing fourth: geometric overlap. They compose; they do not compete.
Shipped A–F
BVH
where / when / shape
Live primary ANN
HNSW
looks like / means like
ECC substrate
Causal + UNID
why / who cites whom
Research ops
Graph Views
fusion, then promote
Pretty is not the map.
Appearance
splat.sog
Humans, Spark-style viewers, Agent Workspace backdrops. Marble Gaussians belong here. Optional cosmetic fill must be labeled non-metric.
Structure
BVH leaves
Object vs Event, AABB, chain evidence. Marble collider meshes rhyme with this column. W1 export exists; live publish does not.
A handle, not a second brain.
Every spatial payload may carry an optional VectorRef. Default is none — pure geometry. Feature kNN stays on HNSW. Geometric kNN on the BVH is AABB-center proximity, not cosine. Phase F helpers compose the two without inlining embeddings.
Shipped is not the same as live.
Done on Plane
- WEFT-716–720 Phases A–E (tree, tags, service, COW, CLI)
- WEFT-721–723 VectorRef + Phase F join helpers
- WEFT-708/709 W0 scene stub + W1 geometric partition (export)
- WEFT-713 Urth E0 doctrine + world-builder expert
Residual (docs, not board)
open
Live BVH publish
W1 still writes bvh_published: false. Structure extract does not enter the index.
open
Daemon spatial RPC
spatial_cli_e2e is ignored. Reattach via SpatialService.
open
F9 promote
Graph Views research exists; stable components do not yet mint Object leaves.
open
Urth E1 / E2
Region hierarchy and OSM basemap ingest were unchecked on E0.
open
Panopticon
ADR-069 reverse join by chain_seq is still proposed.
open
DiskANN cold tier
Deferred, not disqualified. HNSW stays primary.
What turned up this session.
New papers and products since the 0.8 cut. Click a card for the seam. Deep dives live under docs/research/spatial-intelligence-2026/.
S1 · Apply language
Marble + Atlas
World Labs dual export (splats + collider mesh) is the commercial form of ADR-078. Atlas (2026-09-01) is an omni camera-controlled model. Spark 2.0 streams 3DGS with LOD.
S2 · Compose as priors
Genie 3 · Cosmos · WBench
Interactive video worlds. Minutes of consistency, not a surveyed planet. May feed LeWM rollouts. Not Urth geometry.
S3 · Apply pipeline
VGGT · MASt3R · SpatialLM
Feed-forward reconstruction can sit before overnight COLMAP. SpatialLM proposes indoor layout from noisy RGB video — a W1 layout proposer with vector: none.
S4 · Apply hierarchy
HOV-SG · ConceptGraphs
Floor → room → object graphs. Embeddings stay on VectorRef / HNSW. Geometry stays in the BVH. Promote, do not flatten.
S5 · Apply appearance LOD
CityGaussian · Octree-GS
Large-scale splat LOD is the appearance twin of Urth L2–L4 and region-sharded BVH. One planetary Gaussian train is forbidden.
S6 · Watch / visual index
V-JEPA 2.1
Latent predictive WM. Confirms ADR-090: optional sub-layer. Dense features may become a visual HNSW namespace.
S7 · Compose
WorldGraph · SuperSplat
rUv typed twin + provenance cards over a splat. Geometry SoT remains BVH, not CSI occupancy.
S8 · Watch
Open video WMs
Astronex-World, Matrix-Game 3.0, HY-World, Yume. Do not pick a champion this cycle.
Directions we are exploring.
Proposed this session (not filed)
- Optional VGGT / MASt3R-SLAM path before COLMAP
- SpatialLM (or equal) as W1 layout proposer
- Octree-GS / CityGaussian appearance LOD keyed to region ids
- Scene-graph hierarchy as Graph View materialization
- Marble dual-export language in product copy (already our split)
- V-JEPA 2.1 dense features as visual index_id — never SoT
Sparse first. Then densify.
The spatial-index decision is closed. The work left is publish, promote, and ingest — plus a 2026 reconstruction stack that can feed the same leaves.
weftos.weavelogic.ai/urth-spatial · 0.8-metaharness · 2026-09-21