Spatial API Architecture
Frames, entities, geometry, time, uncertainty, queries, streaming, and durable state.
Explore this path →Independent developer field guide
APIs That Understand Space
Architecture and implementation guidance for spatial APIs across AI, LLM tools, AR, VR, maps, GPS, 3D engines, mobile apps, glasses, and spatial computing devices.
CAMERA
ANCHOR
OBJECT
MAP
frame: facility:west-wing:v3quality: tracked • 0.08 m
Coverage:Spatial APIAI + LLMWebXROpenXRAR / VRiOS + AndroidUnity + UnrealGPS + Maps3D Tiles + glTF
Choose a path
One Spatial Stack. Six Entry Points.
Start with the layer closest to your product, then follow the links across devices, data, engines, and AI workflows.
AI + LLM Spatial Tools
Ground vision and language in scene entities, deterministic geometry, provenance, and constrained agent tools.
Explore this path →AR / VR Runtime Layers
Design across WebXR, OpenXR, anchors, depth, hands, reference spaces, and capability fallbacks.
Explore this path →Maps + GPS APIs
Build with GeoJSON, coordinate systems, proximity, tracking, versioning, accuracy, and privacy.
Explore this path →Unity + Unreal Integration
Connect durable spatial entities to GameObjects, Actors, commands, assets, and runtime adapters.
Explore this path →Devices + Spatial Computing
Plan for phones, headsets, glasses, sensors, performance tiers, input, and visible privacy state.
Explore this path →Architecture
Preserve Meaning From Sensor to Scene
A reliable spatial interface keeps observation, coordinate transformation, spatial computation, domain meaning, and presentation distinct. This makes it possible to replace a detector, device, engine, or renderer without losing the product’s durable entities.
Every spatial value should answer: what is it, relative to what, at what time, in which units, and with what confidence?
Read the complete modelDeliver
HTTP, streaming, SDKs, tool calls, subscriptions
State
Entities, revisions, permissions, anchors, workflows
Reason
Distance, containment, visibility, routes, semantics
Observe
Maps, cameras, depth, GPS, engines, sensors
Portable contract
Use Stable Entities, Not Runtime Handles
A browser object, OpenXR space, Unity GameObject, Unreal Actor, or AR anchor can disappear. Product identity must survive.
JSON
{
"entity": "pump-2048",
"revision": 17,
"frame": "plant:a:v3",
"position_m": [12.84, 1.05, -6.22],
"orientation_xyzw": [0, 0.7071, 0, 0.7071],
"observed_at": "2026-10-20T18:30:00Z",
"accuracy_m": 0.08,
"capabilities": ["select", "annotate"]
}A contract that travels
Maps: resolve the entity into geographic or facility coordinates.
XR: transform the same entity into the current tracking space.
AI: expose it as a typed tool target with provenance and permissions.
Engines: present it through a GameObject or Actor without making the runtime object authoritative.
Platform layers
Choose the Lowest Layer by Product Need
Distribution, performance, device access, privacy, and content scale determine the right runtime—not keyword popularity.
| Layer | Best for | Owns | Keep above it |
|---|---|---|---|
| WebXR | Link-based immersive web experiences | Browser session, views, poses, input | Durable entities, shared anchors, domain workflows |
| OpenXR | Native and engine-based multi-runtime apps | Runtime spaces, composition, input, extensions | Product identity, permissions, cloud state |
| Mobile AR | Handheld placement, scanning, geospatial AR | Camera tracking, device sensors, local anchors | Content records, moderation, cross-device state |
| Maps + GPS | Global coordinates, regions, routes, tracking | Geographic features and location observations | Experience logic, precision policy, asset delivery |
| Game engine | Interactive 3D, simulation, rendering | Scene objects, physics, assets, local input | Durable domain state and canonical coordinates |
Latest field notes
Spatial Systems Journal
Long-form architecture and implementation guides with one authoritative editorial source per article.
ARCore Geospatial API Design
Architecture patterns for global-scale AR: localization states, anchors, altitude, heading, fallback UX, content delivery, privacy, and testing in the real world.
Read the guide →
visionOS Spatial Architecture
A platform-neutral architecture for visionOS spatial apps, covering presentation modes, RealityKit entities, anchors, scene state, input, shared data, and graceful immersion.
Read the guide →
Unity XR Integration Patterns
How to connect a spatial backend to Unity XR without coupling network models to GameObjects, including adapters, interactors, anchors, async state, and testing.
Read the guide →
Unreal + OpenXR Architecture
A portable architecture for Unreal XR projects that separates OpenXR runtime concerns, Unreal actors, spatial backend state, coordinate conversion, and extensions.
Read the guide →
Streaming 3D Worlds
How to deliver city-scale and world-scale 3D content using hierarchical tiles, glTF assets, metadata, level of detail, caching, and queryable spatial services.
Read the guide →
Spatial API Security & Privacy
A threat-modeling guide for spatial systems that handle precise location, camera imagery, room maps, anchors, 3D assets, and device or agent credentials.
Read the guide →FAQ
Spatial API Questions
Clear definitions for teams choosing data models, runtime layers, engines, and privacy boundaries.
What is a spatial API?
A spatial API is an interface for entities, geometry, poses, relationships, and queries in a physical, geographic, or virtual space. A useful contract identifies the reference frame, units, time, and uncertainty rather than returning ambiguous coordinates.
Does SpatialAPI.xyz provide a hosted API?
No. SpatialAPI.xyz is an independent developer publication and architecture guide. It does not claim to operate a live spatial data service, standards body, app store, or device platform.
How are spatial APIs used with AI and LLMs?
Models can resolve language and interpret images, while spatial services provide deterministic transforms, distance, containment, visibility, routes, and actions. The model orchestrates typed tools instead of inventing geometry.
What is the difference between WebXR and OpenXR?
WebXR is a browser-facing web API for immersive sessions. OpenXR is a native standard between an application or engine and an XR runtime. A product-specific spatial API usually sits above either one.
Can one spatial backend support iOS, Android, Unity, Unreal, and the web?
Yes, when durable entity IDs, coordinate frames, assets, permissions, and commands are platform-neutral. Each client uses an adapter to resolve that state into its own runtime and capability set.
How should camera and location data be protected?
Collect the minimum needed, process locally when practical, use scoped authorization, control precision and retention, expose deletion and sharing state, and validate every agent or client tool call.
Start at the boundary
Make Every Coordinate Explain Itself
Define identity, frame, time, units, uncertainty, and authority before choosing endpoints or SDKs.
Open the spatial API guide