Technical references for engine contributors and game programmers who need subsystem behavior, ownership, or performance details. For scene and asset editing without code, start with Working in the editor. Prefer guides/ for task-based instructions.
Runtime
- Architecture
- Lifecycle
- Frontends and drivers
- Platforms
- Session services
- Scenes and gameplay
- Actor communication —
hi.actors/Actors.*, messages, name-keyed fields - Refs
- Replication wire version — current hook and codec limits
Presentation and simulation
- Coordinate space — axes, handedness, euler, cameras, clip depth
- Rendering · Renderer architecture · Frame governor · Pipeline compilation
- Skeletal animation — skeletons, clips, graphs, layers, events, foot IK, root motion, joint sockets
- GPU particles
- Visual Zones · Volumetric media
- Input · Audio · Physics
- Motion Kit · Temporal Kit
- UI documents — data-driven
.ui.jsonscreens: slots, events, animation, editor
Assets
- Assets and Shinra
- Prefabs
- Asset residency
- Asset formats
- Document schemas — every authored JSON kind: registry, envelope, rendered JSON Schemas, validation and current versions
Editor host
- UI and editor — chrome, command palette, profiler, game
hi.editorSDK, Editor MCP (editor-only) - Editor asset hot reload — daemon events, render-thread pause, and in-place rebind vs full scene re-instantiation
- Editor project selector