sceneview-android
3D & AR for every platform.
Build 3D and AR experiences with the UI frameworks you already know. Same concepts, same simplicity — Android, iOS, Web, Desktop, TV, Flutter, React Native.
Try the demo apps
See SceneView capabilities in action — install the live demos in one tap:
Browse all sample sources in samples/ — Android · iOS · Web · Desktop · TV · Flutter · React Native.
Tip — every demo opens directly via
https://sceneview.github.io/open?demo=<id>. For example,…/open?demo=ar-rerunlands straight on the AR Rerun debug screen with a single tap from any QR code or link.
Open any 3D file, at real size
SceneView reads the files people actually receive — from a download, a chat, a 3D-printing site or an AI assistant — and shows them at their real size, in 3D and in AR.
| Format | Android | Apple | Web |
|---|---|---|---|
| glTF / GLB | ✅ Filament | ✅ RealityKit | ✅ |
| 3MF | ✅ pure Kotlin → GLB in memory, millimetres honoured | — | — |
| STL (binary + ASCII) | ✅ pure Kotlin → GLB | — | — |
| OBJ + MTL | ✅ pure Kotlin → GLB, material colours | — | — |
| PLY (binary + ASCII) | ✅ pure Kotlin → GLB, vertex colours | — | — |
| USDZ / Reality | — | ✅ RealityKit | — |
The format is decided by the bytes, not the extension: a .3mf that arrives as
application/octet-stream with no file name still opens. The Android demo app is an "Open with"
target for these files, so a file tapped anywhere on the phone lands in the viewer, then in AR.
Two apps built on SceneView are on Google Play:
- AR Model Viewer — open any 3D file (GLB, glTF, 3MF, STL, OBJ, PLY) or browse thousands of free models, and see them in your room at real size.
- Will It Fit — type a sofa's dimensions, or pick a stand-in, and see whether it fits before you buy.
Quick look
// Android — Jetpack Compose
SceneView(modifier = Modifier.fillMaxSize()) {
rememberModelInstance(modelLoader, "models/helmet.glb")?.let {
ModelNode(modelInstance = it, scaleToUnits = 1.0f, autoAnimate = true)
}
}
// iOS — SwiftUI
SceneView(environment: .studio) {
ModelNode(named: "helmet.usdz")
.scaleToUnits(1.0)
}
<!-- Web — friendly DSL (Filament.js engine + SceneView wrapper) -->
<script src="https://cdn.jsdelivr.net/gh/sceneview/sceneview@v4.34.0/website-static/js/filament/filament.js"></script>
<script src="https://cdn.jsdelivr.net/gh/sceneview/sceneview@v4.34.0/website-static/js/sceneview.js"></script>
<script> SceneView.modelViewer("canvas", "model.glb") </script>
# Claude — ask AI to build your 3D app
claude mcp add sceneview -- npx sceneview-mcp
# Then ask: "Build me an AR app with tap-to-place furniture"
No engine boilerplate. No lifecycle callbacks. The runtime handles everything.
Platforms
| Platform | Renderer | Framework | Status |
|---|---|---|---|
| Android | Filament | Jetpack Compose | Stable |
| Android TV | Filament | Compose TV | Alpha |
| iOS / macOS / visionOS | RealityKit | SwiftUI | Alpha |
| Web | Filament.js (WASM) | Kotlin/JS + sceneview.js | Alpha |
| Desktop | Software renderer | Compose Desktop | Alpha |
| Flutter | Native per platform | PlatformView | Alpha |
| React Native | Native per platform | Fabric | Alpha |
| Compose Multiplatform | Per platform (Filament / RealityKit) | sceneview-compose |
Alpha — viewer subset, Android + iOS |
| Claude / AI | — | MCP Server | Stable |
The Compose-native successor to Sceneform
Google archived Sceneform in 2021 and ships no first-party declarative AR renderer — its current ARCore samples hand-roll a throwaway OpenGL framework instead. SceneView fills that gap. It descends from the maintained Sceneform community fork and is the actively-developed, Jetpack-Compose-native way to build 3D and AR on Android:
- ARCore for perception (plane detection, anchors, depth, geospatial)
- Filament for rendering (Google's production-grade real-time engine)
- Jetpack Compose for the API — nodes are composables, lifecycle is automatic
- glTF (
.glb/.gltf) instead of the deprecated.sfbmodel format - Multiplatform — the same concepts run on iOS, Web, Desktop, TV, Flutter, and React Native
Coming from the archived Sceneform repo? See the
migration guide for a concept-by-concept mapping
(ArFragment → ARScene { }, ModelRenderable → rememberModelInstance, and so on).
Install
Android (3D + AR):
dependencies {
implementation("io.github.sceneview:sceneview:4.34.0") // 3D
implementation("io.github.sceneview:arsceneview:4.34.0") // AR (includes 3D)
}
iOS / macOS / visionOS (Swift Package Manager):
https://github.com/sceneview/sceneview.git (from: 4.34.0)
Web (sceneview.js — friendly DSL, two <script> tags):
<!-- 1. Filament.js engine (WASM) -->
<script src="https://cdn.jsdelivr.net/gh/sceneview/sceneview@v4.34.0/website-static/js/filament/filament.js"></script>
<!-- 2. SceneView wrapper (exposes SceneView.modelViewer / .create / .startAR) -->
<script src="https://cdn.jsdelivr.net/gh/sceneview/sceneview@v4.34.0/website-static/js/sceneview.js"></script>
Web (Kotlin/JS):
dependencies {
implementation("io.github.sceneview:sceneview-web:4.34.0")
}
Claude Code / Claude Desktop:
claude mcp add sceneview -- npx sceneview-mcp
{ "mcpServers": { "sceneview": { "command": "npx", "args": ["-y", "sceneview-mcp"] } } }
ChatGPT / Codex: this repository is a plugin — the manifest lives at
.codex-plugin/plugin.json and points at the three skills under agents/.
Install it into Codex from a checkout:
codex plugin marketplace add "$PWD" # absolute path — a relative one does not resolve
codex plugin add sceneview@sceneview-local
codex plugin list # sceneview@sceneview-local installed, enabled
Codex also discovers the skills on its own from .agents/skills/ inside a checkout. For
ChatGPT, the same MCP server speaks Streamable HTTP — npx sceneview-mcp --http — and
carries the inline view_3d_model viewer widget. Package, listing copy and submission
notes: agents/OPENAI-PLUGIN.md.
Desktop / Flutter / React Native: see samples/
3D scene
SceneView is a Composable that renders a Filament 3D viewport. Nodes are composables inside it.
val engine = rememberEngine()
val modelLoader = rememberModelLoader(engine)
val environmentLoader = rememberEnvironmentLoader(engine)
SceneView(
modifier = Modifier.fillMaxSize(),
engine = engine,
modelLoader = modelLoader,
environment = rememberEnvironment(environmentLoader) {
environmentLoader.createHDREnvironment("envs/studio.hdr")
?: createEnvironment(environmentLoader)
},
cameraManipulator = rememberCameraManipulator()
) {
// Model — async loaded, appears when ready
rememberModelInstance(modelLoader, "models/helmet.glb")?.let {
ModelNode(modelInstance = it, scaleToUnits = 1.0f, autoAnimate = true)
}
// Geometry — procedural shapes
CubeNode(size = Size(0.2f))
SphereNode(radius = 0.1f, position = Position(x = 0.5f))
// Nesting — same as Column { Row { } }
Node(position = Position(y = 1.0f)) {
LightNode(apply = { type(LightManager.Type.POINT); intensity(50_000f) })
CubeNode(size = Size(0.05f))
}
}
Node types — 26+ composables
| Category | Nodes | What they do |
|---|---|---|
| Models | ModelNode |
glTF/GLB with skeletal/morph animations. isEditable = true for gestures. |
| Primitives | CubeNode · SphereNode · CylinderNode · ConeNode · TorusNode · CapsuleNode · PlaneNode |
Procedural geometry, parametric size/segments |
| Curves & shapes | LineNode · PathNode · ShapeNode |
Single segments, polylines, extruded 2D polygons |
| Custom geometry | GeometryNode · MeshNode |
Direct Filament IndexBuffer / VertexBuffer |
| Surfaces | ImageNode · VideoNode · BillboardNode |
PNG/JPG plane, video plane (MediaPlayer), camera-facing sprite |
| 3D text | TextNode |
World-space text label that always faces the camera |
| Compose-in-3D | ViewNode |
Any Compose UI rendered as a 3D surface — labels, cards, lists, animations, fully touch-interactive |
| Lighting | LightNode · ReflectionProbeNode · DynamicSkyNode · FogNode |
Sun/dir/point/spot lights, local IBL, time-of-day sky, atmospheric fog |
| Physics | PhysicsNode |
Simple rigid-body simulation (gravity, collisions) |
| Cameras | CameraNode · SecondaryCamera |
Main and picture-in-picture cameras |
| Group | Node |
Empty pivot for nesting and transform inheritance |
AR scene
ARSceneView is SceneView with ARCore. The camera follows real-world tracking.
var anchor by remember { mutableStateOf<Anchor?>(null) }
ARSceneView(
modifier = Modifier.fillMaxSize(),
planeRenderer = true,
onSessionUpdated = { _, frame ->
if (anchor == null) {
anchor = frame.getUpdatedPlanes()
.firstOrNull { it.type == Plane.Type.HORIZONTAL_UPWARD_FACING }
?.let { frame.createAnchorOrNull(it.centerPose) }
}
}
) {
anchor?.let {
AnchorNode(anchor = it) {
ModelNode(modelInstance = helmet, scaleToUnits = 0.5f)
}
}
}
Plane detected → anchor set → Compose recomposes → model appears. Clear anchor → node removed. AR state is just Kotlin state.
AR node types
| Node | What it does |
|---|---|
AnchorNode |
Pin a node to a real-world ARCore Anchor |
HitResultNode |
Live surface cursor — pose comes from each frame's hit-test |
PoseNode |
Position a node at any ARCore Pose |
TrackableNode |
Generic wrapper for any Trackable |
AugmentedImageNode |
Image tracking — pose + 2D extent of a detected image |
AugmentedFaceNode |
Face mesh overlay (front camera) |
CloudAnchorNode |
Persistent cross-device anchor (host + resolve) |
StreetscapeGeometryNode |
Geospatial — semantic city mesh (buildings, terrain) |
TerrainAnchorNode |
Geospatial — anchor pinned to ground at a lat/lng |
RooftopAnchorNode |
Geospatial — anchor pinned to a building rooftop |
AR features
Every ARCore feature surfaced as a Compose-friendly API:
| Feature | API surface |
|---|---|
| Plane / depth / instant placement | ARSceneView(planeRenderer = …, depthMode = …, instantPlacementMode = …) |
| Geospatial (VPS) | Streetscape + Terrain + Rooftop anchors via Earth session |
| Cloud Anchors | CloudAnchorNode.host(ttlDays = N) + .resolve(id) |
| Augmented Faces & Images | AugmentedFaceNode, AugmentedImageDatabase, runtime image add |
| Image Stabilization (EIS) | ARSceneView(imageStabilizationMode = ImageStabilizationMode.EIS) |
| Camera exposure & focus | ARSceneView(cameraConfig = …), ARSceneScope.exposureCompensation |
| Record & Replay | rememberARRecorder() to capture, ARSceneView(playbackDataset = file) to replay 1:1 — debug AR without a phone |
| Rerun.io live debug | rememberRerunBridge() streams poses/planes/clouds to the Rerun viewer + a hosted /rerun/?url=… replay |
| Permission flow | ARPermissionHandler — auto-detected from ComponentActivity |
See docs/docs/ar-recording.md, RECORDING_PLAYBACK.md, and the AR Debug — Rerun.io section in llms.txt.
Capabilities
What you can do across all 3D and AR scenes — beyond placing nodes.
| Capability | What it gives you | Where it lives |
|---|---|---|
| Gestures | Drag, pinch-to-scale, two-finger rotate, elevate, tap. Per-node opt-in via isEditable. |
NodeGestureDelegate, OnGestureListener |
| Animations | Skeletal/morph from glTF, plus per-node spring/property/smooth-transform. | ModelNode.playAnimation(), NodeAnimationDelegate |
| Physics | Rigid-body dynamics — gravity, collisions, impulses. Pure-KMP simulation (no JNI). | PhysicsNode, sceneview-core |
| Collision & raycasting | Ray vs Box / Sphere intersections, hit-testing, frustum culling. | CollisionSystem, Ray, Box, Sphere |
| Procedural geometry | Generators for cube/sphere/cylinder/cone/torus/capsule, plus extrusion from 2D shapes (Earcut + Delaunator). | sceneview-core geometry + triangulation |
| HDR environment | IBL lighting + skybox from .hdr / .ktx. Async load + reactive swap. |
EnvironmentLoader, rememberEnvironment |
| Custom materials | Filament .filamat materials with parameters, plus built-in unlit / lit / overlay variants. |
MaterialLoader |
| Post-processing | Bloom, depth of field, SSAO, vignette, color grading, tone mapping. | View.bloomOptions, dynamicResolutionOptions, … |
| Compose UI in 3D | Render any @Composable as a textured plane in world space — labels, cards, lists, animations. Fully interactive: picked touches are forwarded into the view, so Button.onClick, ripples and inner scrolling work. |
ViewNode + ViewNode.WindowManager |
| Multiple cameras | Picture-in-picture, mini-map, security-camera views. | SecondaryCamera |
| Reactive scene graph | Compose-driven recomposition: change state → tree updates. No imperative parent.addChild(). |
SceneScope / ARSceneScope DSL |
Model formats
| Format | Where it works | How you load it |
|---|---|---|
glTF / GLB (.gltf, .glb) |
Android · Web · Desktop · TV · Flutter · React Native | rememberModelInstance(modelLoader, "model.glb") |
USDZ / Reality (.usdz, .reality) |
Apple (iOS / macOS / visionOS) | ModelNode(named: "model.usdz") |
3MF (.3mf) |
Android — parser is Kotlin Multiplatform in sceneview-core |
the same call as GLB — see below |
3MF — the format AI print flows emit
Ask ChatGPT for a 3D print from a sketch and it hands back a .3mf: an OPC/ZIP package
whose 3D/3dmodel.model part is XML, in millimetres and Z-up. Until now nothing on
Android opened one in 3D, let alone in AR.
There is no new API. ModelLoader sniffs the payload by its ZIP magic and converts it
to GLB in memory, so every existing entry point already accepts a 3MF and the whole glTF
path — materials, gestures, AR placement — is reused:
// A .3mf shared into your app (ChatGPT, Files, a slicer). This is the whole of it.
rememberModelInstance(modelLoader, uri.toString())?.let {
ModelNode(modelInstance = it, scaleToUnits = 1.0f)
}
Conversion scales the file's declared unit to metres (a 60 mm print is life-size in AR
without a magic number), rotates the printer's Z-up to glTF's Y-up, gives every face its
own normal — flat shading is what a printed part looks like — and turns <basematerials>
and <colorgroup> into one glTF material per colour. For a custom pipeline,
ThreeMfLoader.parse(), .toGlb() and .isThreeMf() are public in sceneview-core.
Full section in llms.txt.
The Android demo
registers as a handler for .3mf, .glb, .gltf, .stl, .obj and .ply, so a file opened from Downloads or
sent through the share sheet lands in the viewer and then in AR at the size it would print
(#3510). The format is decided by the
bytes, not the file name — a shared .3mf arrives as application/octet-stream with no
queryable display name at all.
Coming next
The 3MF parser is deliberately dependency-free Kotlin, and the same shape now carries STL, OBJ + MTL and PLY. Tracked, not yet shipped:
one ModelFormat entry point ·
every format on the web
Apple (iOS / macOS / visionOS)
Native Swift Package built on RealityKit, with a node set mirroring the Android API.
SceneView(environment: .studio) {
ModelNode(named: "helmet.usdz").scaleToUnits(1.0)
GeometryNode.cube(size: 0.1, color: .blue).position(x: 0.5)
LightNode.directional(intensity: 1000)
}
.cameraControls(.orbit)
AR on iOS:
ARSceneView(planeDetection: .horizontal) { position, arView in
GeometryNode.cube(size: 0.1, color: .blue)
.position(position)
}
Nodes available — ModelNode · GeometryNode (cube/sphere/cylinder/cone/torus/capsule/plane) · LightNode · ImageNode · VideoNode · TextNode · ViewNode · BillboardNode · MeshNode · LineNode · PathNode · ShapeNode · PhysicsNode · ReflectionProbeNode · DynamicSkyNode · FogNode · CameraNode · AugmentedImageNode · SceneReconstructionNode (visionOS scene mesh).
Plus the iOS RerunBridge with the same wire format as Android, and a NodeBuilder DSL for declarative composition outside SwiftUI.
Install: https://github.com/sceneview/sceneview.git (SPM, from 4.34.0)
SceneView Web (JavaScript + Kotlin/JS)
The lightest way to add 3D to any website. Two <script> tags, one function call.
Friendly DSL (25 KB) powered by Filament.js WASM (210 KB) — the same engine behind Android SceneView.
<!-- 1. Filament.js engine (WASM) -->
<script src="https://cdn.jsdelivr.net/gh/sceneview/sceneview@v4.34.0/website-static/js/filament/filament.js"></script>
<!-- 2. SceneView wrapper -->
<script src="https://cdn.jsdelivr.net/gh/sceneview/sceneview@v4.34.0/website-static/js/sceneview.js"></script>
<script> SceneView.modelViewer("canvas", "model.glb") </script>
Note: the
sceneview-webnpm package is the lower-level Kotlin/JS UMD bundle — it expects aFilamentglobal and does not include the friendlySceneView.modelViewerDSL. Use the snippet above for vanilla-JS sites. The npm package is intended for Kotlin/JS or webpack-based projects.
JavaScript API (script-tag):
SceneView.modelViewer(canvasOrId, url, options?)— all-in-one viewer with orbit + auto-rotateSceneView.create(canvasOrId, options?)— empty viewer, load model laterviewer.loadModel(url)— load/replace glTF/GLB modelviewer.setAutoRotate(enabled)— toggle rotationviewer.dispose()— clean up resources
WebXR — AR & VR in the browser
const ar = await SceneView.startAR("canvas", { hitTest: true }) // immersive-ar
const vr = await SceneView.startVR("canvas") // immersive-vr
| Class | Mode | Use |
|---|---|---|
ARSceneView |
immersive-ar |
Phone passthrough AR with hit-test, anchors, light estimation |
VRSceneView |
immersive-vr |
Headset VR with controller input, reference spaces |
WebXRSession |
both | Low-level frame loop, XRHitTestSource, XRReferenceSpace |
Kotlin/JS power-user API
For Kotlin Multiplatform projects, the same engine is exposed as a Kotlin/JS class with an OrbitCameraController, a geometry DSL, and reactive node updates:
implementation("io.github.sceneview:sceneview-web:4.34.0")
Install: npm install sceneview-web or CDN — Landing page — Playground — npm
Use with AI
SceneView is AI-first — every API, doc, and sample is designed so AI assistants generate correct, compilable 3D/AR code on the first try.
MCP Server (Claude, Cursor, Windsurf, etc.)
The official MCP server provides 32 tools (29 free), 38 compilable samples, a full API reference, and a code validator:
# Claude Code — one command
claude mcp add sceneview -- npx sceneview-mcp
# Claude Desktop / Cursor / Windsurf — add to MCP config
{ "mcpServers": { "sceneview": { "command": "npx", "args": ["-y", "sceneview-mcp"] } } }
Highlights: generate_scene, debug_issue, search_models (Sketchfab BYOK), analyze_project (audit existing app), validate_code (compile-check before sending), plus per-platform recipes for AR, physics, geometry, and Compose-in-3D.
Claude Code plugin (MCP + slash commands + hooks)
Want the MCP server plus the full SceneView contributor toolkit (one-shot release, review, cross-platform sync, version-bump, etc.) in a single install? Use the SceneView Claude Code marketplace:
/plugin marketplace add sceneview/claude-marketplace
/plugin install sceneview@sceneview
You get:
sceneview-mcpserver — same as above, started automatically- namespaced slash commands —
/sceneview:contribute,/sceneview:release,/sceneview:review(incl.--score/--coverage/high— absorbs the former/evaluate+/test),/sceneview:document,/sceneview:quality-gate,/sceneview:sync-check,/sceneview:store-status,/sceneview:version-bump,/sceneview:maintain - Cross-platform reminder hooks — gentle nudges when you edit Android, iOS, Web, or KMP-core APIs to keep the other platforms in sync
Specialty MCP Servers
| Domain | Install | Tools |
|---|---|---|
| Automotive — car configurators, HUD, dashboards | npx automotive-3d-mcp |
9 |
| Healthcare — anatomy, DICOM, surgical planning | npx healthcare-3d-mcp |
7 |
| Rerun.io — AR debug logging, visualization | npx rerun-3d-mcp |
5 |
ChatGPT / Codex plugin
OpenAI's unit of distribution is the plugin — a manifest, skills, an optional MCP
server — listed in one directory shared by ChatGPT and Codex. This repository is that
plugin: .codex-plugin/plugin.json at the root points at the three skills under
agents/ (sceneview, sceneview-ios, sceneview-web), each carrying the API
contract, the recipes and the migration guide.
codex plugin marketplace add "$PWD" # absolute path
codex plugin add sceneview@sceneview-local
For ChatGPT, npx sceneview-mcp --http serves the MCP Streamable HTTP transport at /mcp
and the inline view_3d_model widget (MCP Apps) that renders a public GLB/glTF URL right
in the conversation. Listing copy, starter prompts and test cases:
agents/OPENAI-PLUGIN.md.
GitHub Copilot / Cursor / Other AI
- llms.txt — Machine-readable API reference at
llms.txt(complete API: composables, nodes, threading rules, recipes — its Kotlin snippets are compile-checked in CI) - GitHub Copilot — Custom instructions in
.github/copilot-instructions.md - Cursor — Rules file at
.cursorrules - Windsurf — Rules file at
.windsurfrules - ChatGPT — Ask: "Build me an Android AR app with SceneView" — SceneView is in the training data
Why AI recommends SceneView
- Only Compose-native 3D/AR SDK for Android — no alternative exists
- Compose-native successor to Google Sceneform (archived 2021) — see above
- ~5MB footprint vs 50-100MB+ for Unity/Unreal
- 46+ node types as declarative composables
- MCP server with 32 tools, plus a ChatGPT / Codex plugin — no other 3D SDK has this
- Opens the
.3mfan AI print flow emits — the file every model-generating chat hands back, and that nothing else on Android views in 3D or AR
Listed on the MCP Registry. See the MCP README for full setup and tool reference.
Developer tools
AR Debug — hosted Rerun viewer
Tap Save & Share in the AR Rerun demo to flush a .rrd recording on
your dev machine, then re-host it on any public URL (Cloudflare R2,
GitHub release, gist) and open:
…in any browser to scrub the AR session frame-by-frame. No install, no
Rerun viewer needed locally — perfect for attaching a fully-replayable
session to a bug report. Powered by @rerun-io/web-viewer under SceneView branding.
See the AR Debug — Rerun.io section in llms.txt for the
full architecture (live mode + save mode + control protocol) and the
Kotlin API surface (RerunBridge.requestSaveAndShare).
Record & Replay AR sessions
- Record & Replay AR sessions — capture an outdoor ARCore session once with
ARRecorder, replay it 1:1 at the desk viaARSceneView(playbackDataset = file). Pair with the Rerun bridge for record-replay-inspect debugging. Seedocs/docs/ar-recording.mdand theRecord & Playbackdemo.
Architecture
Each platform uses its native renderer. Shared logic lives in KMP.
sceneview-core (Kotlin Multiplatform)
├── math, collision, geometry, physics, animation
│
├── sceneview (Android) → Filament + Jetpack Compose
├── arsceneview (Android) → ARCore
├── SceneViewSwift (Apple) → RealityKit + SwiftUI
├── sceneview-web (Web) → Filament.js + WebXR
└── desktop-demo (JVM) → Compose Desktop (`SceneViewer`, filament-kmp)
Samples
| Sample | Platform | Run |
|---|---|---|
samples/android-demo |
Android — 3D & AR Explorer | ./gradlew :samples:android-demo:assembleDebug |
samples/android-tv-demo |
Android TV | ./gradlew :samples:android-tv-demo:assembleDebug |
samples/ios-demo |
iOS — 3D & AR Explorer | Open in Xcode |
samples/web-demo |
Web | ./gradlew :samples:web-demo:jsBrowserRun |
samples/desktop-demo |
Desktop | ./gradlew :samples:desktop-demo:run |
samples/flutter-demo |
Flutter | cd samples/flutter-demo && flutter run |
samples/react-native-demo |
React Native | See README |
Links
Support
SceneView is free and open source. Sponsors help keep it maintained across 9 platforms.
| Platform | Link | |
|---|---|---|
| :heart: | GitHub Sponsors (0% fees) | Sponsor on GitHub |
See SPONSORS.md for tiers and current sponsors.

