Overview

Forge Universe (universe.forgesdlc.com) is a proof-of-concept for a declarative 3D scene model that multiple renderers consume in the browser without a build step per demo.

Capabilities

World model

• Scene JSON v1 — versioned document with nodes, camera, and an optional sim block for in-browser rigid-body physics.
• Six solid types — tetrahedron, hexahedron (cube alias), octahedron, dodecahedron, icosahedron, sphere.
• Pose math — translation plus Euler rotations (rx, ry, rz in degrees) applied consistently across renderers.
• Wireframe geometry — Platonic edges derived from vertices; sphere uses configurable great-circle and latitude rings.

Render paths

Path	Technology	Use case
2D projections	SVG	Orthographic and perspective math views (Up2)
Static gallery	SVG wireframes + CSS 3D cube	Lightweight catalog (Us3)
Solid flyout	WebGL dronie + SVG XYZ panels	Inspect one primitive (Ufl)
Drone flythrough	Three.js WebGL + FPS HUD	Multi-solid cinematic orbit (Udr)
Sim bounce	Three.js WebGL + UniverseSim	Gravity, ground, sphere/AABB contacts (Usb)
Construction assets	Three.js ES modules + GLTFLoader	Omniverse GLB + kinematic articulation (Uca)

Simulation

• UniverseSim — semi-implicit Euler integrator with gravity, ground plane, and sphere/AABB contact resolution.
• Pose sync — each step writes body positions into linked node.pose so renderers need no duplicate state.
• Scene-driven — sim.bodies entries reference nodeId; shapes default from node type (sphere vs aabb).
• Docs — Simulation; limits vs NVIDIA Omniverse in Universe vs Omniverse.

Governance

• KS-style hashes — three-letter codes (Ute, Us3, …) on visual roots via hash and data-ks-hash.
• Oracles — JSON scenarios verified with Playwright (tools/universe-verifier/).
• Unit tests — Node test runner on universe-world.js (tools/universe/tests/).

Architecture

assets/scenes/*.json
        │
        ▼
  UniverseWorld  ── validate, pose, wireframes, projection
        │
        ├── UniverseProject2D      (SVG ortho / perspective)
        ├── UniverseStaticCss      (gallery cards)
        ├── UniverseSolidFlyout    (dronie + XYZ panels)
        ├── UniverseDynamicGl      (WebGL + dronie camera)
        ├── UniverseSim            (rigid-body integrator)
        ├── UniverseSimGl          (WebGL + sim stepping)
        └── forge-universe-assets  (GLB + articulation ES modules)

All modules are plain IIFE scripts loaded by static HTML pages. Three.js is vendored for WebGL only.

Hash registry (PoC)

Hash	Slug	Role
Uwv	universe-viewport	Family roll-up
Ute–Ups	primitives	Per-solid gallery roots
Up2	projections-2d	2D demo page
Us3	static-3d	Static gallery
Ufl	solid-flyout	Detail flyout dialog
Udr	dynamic-drone	WebGL flythrough
Usb	sim-bounce	WebGL + rigid-body sim

Out of scope (PoC)

• Server-side or distributed simulation (all physics runs in the browser).
• OpenUSD, RTX, Omniverse Kit, or multi-user live sync — see Universe vs Omniverse.
• Kitchen Sink submodule integration.
• Authentication or multi-user state.